U.S. patent application number 10/202669 was filed with the patent office on 2003-07-31 for aluminum alloy excellent in cutting ability, aluminum alloy materials and manufacturing method thereof.
This patent application is currently assigned to SHOWA DENKO K.K.. Invention is credited to Kitamura, Masakatsu, Matsuoka, Hideaki, Okamoto, Yasuo, Yamanaka, Masaki, Yoshioka, Hiroki.
Application Number | 20030143102 10/202669 |
Document ID | / |
Family ID | 46150176 |
Filed Date | 2003-07-31 |
United States Patent
Application |
20030143102 |
Kind Code |
A1 |
Matsuoka, Hideaki ; et
al. |
July 31, 2003 |
Aluminum alloy excellent in cutting ability, aluminum alloy
materials and manufacturing method thereof
Abstract
A first aluminum alloy of the present invention comprises Mg:
0.3-6 mass %, Si: 0.3-10 mass %, Zn: 0.05-1 mass %, Sr: 0.001-0.3
mass % and the balance being Al and impurities. A second aluminum
alloy further contains one or more selective additional elements
selected from the group consisting of Cu, Fe, Mn, Cr, Zr, Ti, Na
and Ca. Furthermore, a third aluminum alloy comprises Mg: 0.1-6
mass %, Si: 0.3-12.5 mass %, Cu: 0.01 mass % or more but less than
1 mass %, Zn: 0.01-3 mass %, Sr: 0.001-0.5 mass % and the balance
being Al and impurities. Furthermore, a fourth aluminum alloy
further includes one or more optional additional elements selected
from the group consisting of Ti, B, C, Fe, Cr, Mn, Zr, V, Sc, Ni,
Na, Sb, Ca, Sn, Bi and In.
Inventors: |
Matsuoka, Hideaki; (Oyama,
JP) ; Yamanaka, Masaki; (Oyama, JP) ;
Yoshioka, Hiroki; (Oyama, JP) ; Okamoto, Yasuo;
(Kitakata, JP) ; Kitamura, Masakatsu; (Kitakata,
JP) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
SHOWA DENKO K.K.
Tokyo
JP
|
Family ID: |
46150176 |
Appl. No.: |
10/202669 |
Filed: |
July 25, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60311363 |
Aug 13, 2001 |
|
|
|
Current U.S.
Class: |
420/546 ;
148/551; 148/690; 420/532; 420/548 |
Current CPC
Class: |
C22C 21/08 20130101;
C22F 1/043 20130101; C22C 21/04 20130101; C22F 1/047 20130101 |
Class at
Publication: |
420/546 ;
420/548; 148/690; 420/532; 148/551 |
International
Class: |
C22C 021/04 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 25, 2001 |
JP |
2001-224661 |
May 22, 2002 |
JP |
2002-148340 |
Claims
What is claimed is:
1. An aluminum alloy, comprising: Mg: 0.3-6 mass %; Si: 0.3-10 mass
%; Zn: 0.05-1 mass %; Sr: 0.001-0.3 mass %; and the balance being
aluminum and impurities.
2. The aluminum alloy as recited in claim 1, wherein the content of
Mg is 0.5-1.1 mass %.
3. The aluminum alloy as recited in claim 1, wherein the content of
Si is 1.5-5 mass %.
4. The aluminum alloy as recited in claim 1, wherein the content of
Zn is 0.1-0.3 mass %.
5. The aluminum alloy as recited in claim 1, wherein the content of
Sr is 0.005-0.05 mass %.
6. An aluminum alloy, comprising: Mg: 0.3-6 mass %; Si: 0.3-10 mass
%; Zn: 0.05-1 mass %; Sr: 0.001-0.3 mass %; one or more of
selective additional elements selected from the group consisting of
Cu: 0.01 mass % or more but less than 1 mass %, Fe: 0.01-1 mass %,
Mn: 0.01-1 mass %, Cr: 0.01-1 mass %, Zr: 0.01-1 mass %, Ti: 0.01-1
mass %, Na: 0.001-0.5 mass % and Ca: 0.001-0.5 mass %; and the
balance being Aluminum and impurities.
7. The aluminum alloy as recited in claim 6, wherein the content of
Mg is 0.5-1.1 mass %.
8. The aluminum alloy as recited in claim 6, wherein the content of
Si is 1.5-5 mass %.
9. The aluminum alloy as recited in claim 6, wherein the content of
Zn is 0.1-0.3 mass %.
10. The aluminum alloy as recited in claim 6, wherein the content
of Sr is 0.005-0.05 mass %.
11. The aluminum alloy as recited in claim 6, wherein the selective
additional element is Cu.
12. The aluminum alloy as recited in claim 6, wherein the selective
additional element is Fe.
13. The aluminum alloy as recited in claim 6, wherein the selective
additional element is one or more elements selected from the group
consisting Cr and Mn.
14. The aluminum alloy as recited in claim 6, wherein the selective
additional element is Zr.
15. The aluminum alloy as recited in claim 6, wherein the selective
additional element is Ti.
16. The aluminum alloy as recited in claim 6, wherein the selective
additional element is one or more elements selected from the group
consisting of Na and Ca.
17. The aluminum alloy as recited in claim 6, wherein the content
of Cu is 0.1-0.3 mass %.
18. The aluminum alloy as recited in claim 6, wherein the content
of Fe is 0.1-0.3 mass %.
19. The aluminum alloy as recited in claim 6, wherein the content
of Mn is 0.1-0.3 mass %.
20. The aluminum alloy as recited in claim 6, wherein the content
of Cr is 0.1-0.3 mass %.
21. The aluminum alloy as recited in claim 6, wherein the content
of Zr is 0.1-0.3 mass %.
22. The aluminum alloy as recited in claim 6, wherein the content
of Ti is 0.1-0.3 mass %.
23. The aluminum alloy as recited in claim 6, wherein the content
of Na is 0.005-0.3 mass %.
24. The aluminum alloy as recited in claim 6, wherein the content
of Ca is 0.005-0.3 mass %.
25. An aluminum alloy material composed of an aluminum alloy,
wherein the aluminum alloy comprises Mg: 0.3-6 mass %, Si: 0.3-10
mass %, Zn: 0.05-1 mass %, Sr: 0.001-0.3 mass %, and the balance
being aluminum and impurities, as a chemical composition thereof,
and wherein a mean particle diameter of Si particle is 1-5 .mu.m
and a mean aspect ratio of Si particle is 1-3, as an alloy texture
of the aluminum alloy.
26. The aluminum alloy material as recited in claim 25, wherein the
mean particle diameter of the Si particle is 3 .mu.m or less.
27. The aluminum alloy material as recited in claim 25, wherein the
mean aspect ratio of the Si particle is 2 or less.
28. An aluminum alloy material composed of aluminum alloy, wherein
the aluminum alloy comprises Mg: 0.3-6 mass %, Si: 0.3-10 mass %,
Zn: 0.05-1 mass %, Sr: 0.001-0.3 mass %, one or more selective
additional elements selected from the group consisting of Cu: 0.01
mass % or more but less than 1 mass %, Fe: 0.01-1 mass %, Mn:
0.01-1 mass %, Cr: 0.01-1 mass %, Zr: 0.01-1 mass %, Ti: 0.01-1
mass %, Na: 0.001-0.5 mass % and Ca: 0.001-0.5 mass %, as a
chemical composition thereof, and the balance being aluminum and
impurities, and wherein a mean particle diameter of Si particle is
1-5 .mu.m and a mean aspect ratio of Si particle is 1-3, as an
alloy texture of the aluminum alloy.
29. An aluminum alloy material as recited in claim 28, wherein the
mean particle diameter of the Si particle is 3 .mu.m or less.
30. The aluminum alloy material as recited in claim 28, wherein the
mean aspect ratio of the Si particle is 2 or less.
31. A method for manufacturing an aluminum alloy material, the
method comprising: making a billet at a casting rate of 10-180
mm/min., the billet composed of aluminum alloy comprising Mg: 0.3-6
mass %, Si: 0.3-10 mass %, Zn: 0.05-1 mass %, Sr: 0.001-0.3 mass %,
and the balance being aluminum and impurities; homogenizing the
billet at 400-570.degree. C. for 6 hours or more to obtain a
homogenized billet; extruding the homogenized billet at a billet
temperature of 300-550.degree. C., an extrusion rate of 0.5-100
m/min. and an extrusion ratio of 10-200 into an extruded article
having a predetermined configuration; executing a solution
treatment to the extruded article at 400-570.degree. C. for 1 hour
or more; and aging the solution treated extruded article at
90-300.degree. C. for 1-30 hours.
32. The method for manufacturing an aluminum alloy material as
recited in claim 31, wherein the casting rate is 30-130 mm/min.
33. The method for manufacturing an aluminum alloy material as
recited in claim 31, wherein the homogenization is performed at
500-545.degree. C. for 10 hours or more.
34. The method for manufacturing an aluminum alloy material as
recited in claim 31, wherein the extrusion is performed at the
billet temperature of 350-500.degree. C., the extrusion rate of
2-30 m/min. and the extrusion ratio of 20-85.
35. The method for manufacturing an aluminum alloy material as
recited in claim 31, wherein the solution treatment is performed at
500-545.degree. C. for 3 hours or more.
36. The method for manufacturing an aluminum alloy material as
recited in claim 31, wherein the aging is performed at
140-200.degree. C. for 3-20 hours.
37. The method for manufacturing an aluminum alloy material as
recited in claim 31, wherein the solution treated extruded article
is drawn at a reduction rate of 5-30% into a predetermined
configuration, and thereafter the aging is performed.
38. The method for manufacturing an aluminum alloy material as
recited in claim 37, wherein the reduction rate of the drawing is
10-20%.
39. A method for manufacturing an aluminum alloy material,
comprising: making a billet at a casting rate of 10-180 mm/min.,
the billet composed of aluminum alloy comprising Mg: 0.3-6 mass %,
Si: 0.3-10 mass %, Zn: 0.05-1 mass %, Sr: 0.001-0.3 mass %, one or
more selective additional elements selected from the group
consisting of Cu: 0.01 mass % or more but less than 1 mass %, Fe:
0.01-1 mass %, Mn: 0.01-1 mass %, Cr: 0.01-1 mass %, Zr: 0.01-1
mass %, Ti: 0.01-1 mass %, Na: 0.001-0.5 mass % and Ca: 0.001-0.5
mass %, and the balance being aluminum and impurities; homogenizing
the billet at 400-570.degree. C. for 6 hours or more to obtain a
homogenized billet; extruding the homogenized billet at a billet
temperature of 300-550.degree. C., an extrusion rate of 0.5-100
m/min., and an extrusion ratio of 10-200 into an extruded article
having a predetermined configuration; executing a solution
treatment to the extruded article at 400-570.degree. C. for 1 hour
or more; and aging the solution treated extruded article at
90-300.degree. C. for 1-30 hours.
40. The method for manufacturing an aluminum alloy material as
recited in claim 39, wherein the casting rate is 30-130 mm/min.
41. The method for manufacturing an aluminum alloy material as
recited in claim 39, wherein the homogenization is performed at
500-545.degree. C. for 10 hours or more.
42. The method for manufacturing an aluminum alloy material as
recited in claim 39, wherein the extrusion is performed at the
billet temperature of 350-500.degree. C., the extrusion rate of
2-30 m/min. and the extrusion ratio of 20-85.
43. The method for manufacturing an aluminum alloy material s
recited in claim 39, wherein the solution treatment is performed at
500-545.degree. C. for 3 hours or more.
44. The method for manufacturing an aluminum alloy material as
recited in claim 39, wherein the aging is performed at
140-200.degree. C. for 3-20 hours.
45. The method for manufacturing an aluminum alloy material as
recited in claim 39, wherein the solution treated extruded article
is drawn at a reduction rate of 5-30% into a predetermined
configuration, and thereafter the aging is performed.
46. The method for manufacturing an aluminum alloy material as
recited in claim 45, wherein the reduction rate of the drawing is
10-20%.
47. An aluminum alloy, comprising: Mg: 0.1-6 mass %; Si: 0.3-12.5
mass %; Cu: 0.01 mass % or more but less than 1 mass %; Zn: 0.01-3
mass %; Sr: 0.001-0.5 mass %; and the balance being aluminum and
impurities.
48. The aluminum alloy as recited in claim 47, wherein the content
of Mg is 0.3-5 mass %.
49. The aluminum alloy as recited in claim 47, wherein the content
of Si is 0.8-12 mass %.
50. The aluminum alloy as recited in claim 47, wherein the content
of Cu is 0.1-0.8 mass %.
51. The aluminum alloy as recited in claim 47, wherein the content
of Zn is 0.05-1.5 mass %.
52. The aluminum alloy as recited in claim 47, wherein the content
of Sr is 0.005-0.3 mass %.
53. An aluminum alloy, comprising: Mg: 0.1-6 mass %; Si: 0.3-12.5
mass %; Cu: 0.01 mass % or more but less than 1 mass %; Zn: 0.01-3
mass %; Sr: 0.001-0.5 mass %; one or more of selective additional
elements selected from the group consisting of Ti: 0.001-1 mass %,
B: 0.0001-0.03 mass %, C: 0.0001-0.5 mass %, Fe: 0.01-1 mass %, Cr:
0.01-1 mass %, Mn: 0.01-1 mass %; Zr: 0.01-1 mass %, V: 0.01-1 mass
%, Sc: 0.0001-0.5 mass %, Ni: 0.005-1 mass %, Na: 0.001-0.5 mass %,
Sb: 0.001-0.5 mass %, Ca: 0.001-0.5 mass %, Sn: 0.01-1 mass %, Bi:
0.01-1 mass %, and In: 0.001-0.5 mass %; and the balance being
Aluminum and impurities.
54. The aluminum alloy as recited in claim 53, wherein the content
of Mg is 0.3-5 mass %.
55. The aluminum alloy as recited in claim 53, wherein the content
of Si is 0.8-12 mass %.
56. The aluminum alloy as recited in claim 53, wherein the content
of Cu is 0.1-0.8 mass %.
57. The aluminum alloy as recited in claim 53, wherein the content
of Zn is 0.05-1.5 mass %.
58. The aluminum alloy as recited in claim 53, wherein the content
of Sr is 0.005-0.3 mass %.
59. The aluminum alloy as recited in claim 53, wherein the
selective additional element is one or more elements selected from
the group consisting of Ti, B, C and Sc.
60. The aluminum alloy as recited in claim 53, wherein the
selective additional element is Fe.
61. The aluminum alloy as recited in claim 53, wherein the
selective additional element is one or more elements selected from
the group consisting Cr and Mn.
62. The aluminum alloy as recited in claim 53, wherein the
selective additional element is one or more elements selected from
the group consisting Zr and V.
63. The aluminum alloy as recited in claim 53, wherein the
selective additional element is Ni.
64. The aluminum alloy as recited in claim 53, wherein the
selective additional element is one or more elements selected from
the group consisting Na, Sb and Ca.
65. The aluminum alloy as recited in claim 53, wherein the
selective additional element is one or more elements selected from
the group consisting Sn, Bi and In.
66. The aluminum alloy as recited in claim 53, wherein the content
of Ti is 0.003-0.5 mass %.
67. The aluminum alloy as recited in claim 53, wherein the content
of B is 0.0005-0.01 mass %.
68. The aluminum alloy as recited in claim 53, wherein the content
of C is 0.001-0.3 mass %.
69. The aluminum alloy as recited in claim 53, wherein the content
of Fe is 0.05-0.7 mass %.
70. The aluminum alloy as recited in claim 53, wherein the content
of Cr is 0.03-0.7 mass %.
71. The aluminum alloy as recited in claim 53, wherein the content
of Mn is 0.03-0.7 mass %.
72. The aluminum alloy as recited in claim 53, wherein the content
of Zr is 0.03-0.7 mass %.
73. The aluminum alloy as recited in claim 53, wherein the content
of V is 0.03-0.7 mass %.
74. The aluminum alloy as recited in claim 53, wherein the content
of Sc is 0.01-0.3 mass %.
75. The aluminum alloy as recited in claim 53, wherein the content
of Ni is 0.03-0.7 mass %.
76. The aluminum alloy as recited in claim 53, wherein the content
of Na is 0.005-0.3 mass %.
77. The aluminum alloy as recited in claim 53, wherein the content
of Sb is 0.005-0.3 mass %.
78. The aluminum alloy as recited in claim 53, wherein the content
of Ca is 0.005-0.3 mass %.
79. The aluminum alloy as recited in claim 53, wherein the content
of Sn is 0.05-0.5 mass %.
80. The aluminum alloy as recited in claim 53, wherein the content
of Bi is 0.05-0.5 mass %.
81. The aluminum alloy as recited in claim 53, wherein the content
of In is 0.01-0.3 mass %.
82. An aluminum alloy material composed of aluminum alloy, wherein
the aluminum alloy comprises Mg: 0.1-6 mass %, Si: 0.3-12.5 mass %,
Cu: 0.01 mass % or more but less than 1 mass %, Zn: 0.01-3 mass %,
Sr: 0.001-0.5 mass %, and the balance being aluminum and
impurities, wherein, in a metal texture, a mean dendrite arm
spacing is 1-200 .mu.m, a dendrite boundary zone includes eutectic
Si particles of 0.01-5 .mu.m of a mean particle diameter and other
second phase particles, and an eutectic lamella texture in which a
mean skeleton line length (Lm) in a longitudinal direction is 0.5
.mu.m or more and a mean width (Wm) is 0.5 .mu.m or more is formed
in a shape of a network.
83. The aluminum alloy as recited in claim 82, wherein, in the
eutectic lamella texture, the eutectic Si particles and other
second phase particles exist 500 pieces/mm.sup.2 or more in total,
and the area share of these particles is 0.1-50%.
84. The aluminum alloy as recited in claim 82, wherein the mean
dendrite arm spacing is 3-100 .mu.m.
85. The aluminum alloy as recited in claim 82, wherein the mean
particle diameter of the eutectic Si particle is 0.1-3 .mu.m.
86. The aluminum alloy as recited in claim 82, wherein the eutectic
lamella texture has a mean skeleton line length (Lm) of 3 .mu.m or
more and a mean width (Wm) of 1 .mu.m or more.
87. The aluminum alloy as recited in claim 82, wherein a mean ratio
(L/Wm) of the skeleton line length to the skeleton width in the
eutectic lamella texture is 3 or more.
88. The aluminum alloy as recited in claim 83, wherein the eutectic
Si particles and other second phase particles exist 1,000
pieces/mm.sup.2 or more in total.
89. The aluminum alloy as recited in claim 83, wherein the area
share of the eutectic Si particles and other second phase particles
is 0.3-40%.
90. An aluminum alloy material composed of an aluminum alloy,
wherein the aluminum alloy comprises Mg: 0.1-6 mass %; Si: 0.3-12.5
mass %; Cu: 0.01 mass % or more but less than 1 mass %; Zn: 0.01-3
mass %; Sr: 0.001-0.5 mass %; one or more of selective additional
elements selected from the group consisting of Ti: 0.001-1 mass %,
B: 0.0001-0.03 mass %, C: 0.0001-0.5 mass %, Fe: 0.01-1 mass %, Cr:
0.01-1 mass %, Mn: 0.01-1 mass %, Zr: 0.01-1 mass %, V: 0.01-1 mass
%, Sc: 0.0001-0.5 mass %, Ni: 0.005-1 mass %, Na: 0.001-0.5 mass %,
Sb: 0.001-0.5 mass %, Ca: 0.001-0.5 mass %, Sn: 0.01-1 mass %, Bi:
0.01-1 mass %, and In: 0.001-0.5 mass %; and the balance being
Aluminum and impurities, and wherein, in a metal texture, a mean
dendrite arm spacing is 1-200 .mu.m, a dendrite boundary zone
includes eutectic Si particles of 0.01-5 .mu.m of mean particle
diameters and other second phase particles, and an eutectic lamella
texture in which a mean skeleton line length (Lm) in a longitudinal
direction is 0.5 .mu.m or more and a mean width (Wm) is 0.5 .mu.m
or more is formed in a shape of a network.
91. The aluminum alloy as recited in claim 90, wherein, in the
eutectic lamella texture, the eutectic Si particles and other
second phase particles exist 500 pieces/mm.sup.2 or more in total,
and the area share of these particles is 0.1-50%.
92. The aluminum alloy as recited in claim 90, wherein the mean
dendrite arm spacing is 3-100 .mu.m.
93. The aluminum alloy as recited in claim 90, wherein the mean
particle diameter of the eutectic Si particle is 0.1-3 .mu.m.
94. The aluminum alloy as recited in claim 90, wherein the eutectic
lamella texture has a mean skeleton line length (Lm) of 3 .mu.m or
more and a mean width (Wm) of 1 .mu.m or more.
95. The aluminum alloy as recited in claim 90, wherein the mean
ratio (L/Wm) of the skeleton line length to the skeleton width in
the eutectic lamella texture is 3 or more.
96. The aluminum alloy as recited in claim 91, wherein the eutectic
Si particles and other second phase particles exist 1,000
pieces/mm.sup.2 or more in total.
97. The aluminum alloy as recited in claim 91, wherein the area
share of the eutectic Si particles and other second phase particles
is 0.3-40%.
98. A method for manufacturing an aluminum alloy material, the
method comprising: continuously casting molten aluminum alloy to
obtain a shape member having a prescribed cross section at a
casting rate of 30-5000 mm/min. and a cooling rate of
10-600.degree. C./sec., the molten aluminum alloy comprising Mg:
0.1-6 mass %, Si: 0.3-12.5 mass %, Cu: 0.01 mass % or more but less
than 1 mass %, Zn: 0.01-3 mass %, Sr: 0.001-0.5 mass % and the
balance being aluminum and impurities and held at the solidus
temperature or more; thereafter aging the shape member at
100-300.degree. C. for 0.5-100 hours.
99. The method for manufacturing an aluminum alloy material as
recited in claim 98, wherein the casting rate is 100-2000
mm/min.
100. The method for manufacturing an aluminum alloy material as
recited in claim 98, wherein the cooling rate is 30-300.degree.
C./sec.
101. The method for manufacturing an aluminum alloy material as
recited in claim 98, wherein the aging is performed at
120-220.degree. C. for 1-30 hours.
102. The method for manufacturing an aluminum alloy material as
recited in claim 98, wherein the shape member is a non-hollow
member.
103. The method for manufacturing an aluminum alloy material as
recited in claim 98, wherein the shape member circumscribes to a
circle with a diameter of 10-150 mm in cross section.
104. The method for manufacturing an aluminum alloy material as
recited in claim 98, further comprising a step of eliminating a
surface layer portion of 0.1-10 mm depth from the continuously cast
shape member.
105. The method for manufacturing an aluminum alloy material as
recited in claim 104, wherein the eliminated surface layer portion
is 0.2-5 mm in depth.
106. The method for manufacturing an aluminum alloy material as
recited in claim 98, further comprising the step of performing a
secondary forming processing of a cross-sectional area decreasing
ratio of 30% or less to the shape member after the continuous
casting at a temperature of 400.degree. C. or below.
107. The method for manufacturing an aluminum alloy material as
recited in claim 106, wherein the processing temperature is
250.degree. C. or below.
108. The method for manufacturing an aluminum alloy material as
recited in claim 106, wherein the cross-sectional area decreasing
ratio is 20% or less.
109. A method for manufacturing an aluminum alloy material, the
method comprising: continuously casting molten aluminum alloy to
obtain a shape member having a prescribed cross section at a
casting rate of 30-5,000 mm/min. and a cooling rate of
10-600.degree. C./sec., the molten aluminum alloy comprising Mg:
0.1-6 mass %, Si: 0.3-12.5 mass %, Cu: 0.01 mass % or more but less
than 1 mass %, Zn: 0.01-3 mass %, Sr: 0.001-0.5 mass %, one or more
of selective additional elements selected from the group consisting
of Ti: 0.001-1 mass %, B: 0.0001-0.03 mass %, C: 0.0001-0.5 mass %,
Fe: 0.01-1 mass %; Cr: 0.01-1 mass %, Mn: 0.01-1 mass %, Zr: 0.01-1
mass %, V: 0.01-1 mass %, Sc: 0.0001-0.5 mass %, Ni: 0.005-1 mass
%, Na: 0.001-0.5 mass %, Sb: 0.001-0.5 mass %, Ca: 0.001-0.5 mass
%, Sn: 0.01-1 mass %, Bi: 0.01-1 mass %, In: 0.001-0.5 mass %, and
the balance being aluminum and impurities and held at the solidus
temperature or more; thereafter aging the shape member at
100-300.degree. C. for 0.5-100 hours.
110. The method for manufacturing an aluminum alloy material as
recited in claim 109, wherein the casting rate is 100-2,000
mm/min.
111. The method for manufacturing an aluminum alloy material as
recited in claim 109, wherein the cooling rate is 30-300.degree.
C./sec.
112. The method for manufacturing an aluminum alloy material as
recited in claim 109, wherein the aging is performed at
120-220.degree. C. for 1-30 hours.
113. The method for manufacturing an aluminum alloy material as
recited in claim 109, wherein the shape member is a non-hollow
member.
114. The method for manufacturing an aluminum alloy material as
recited in claim 109, wherein the shape member circumscribes to a
circle with a diameter of 10-150 mm in cross section.
115. The method for manufacturing an aluminum alloy material as
recited in claim 109, further comprising a step of eliminating a
surface layer portion of 0.1-10 mm depth from the continuously cast
shape member.
116. The method for manufacturing an aluminum alloy material as
recited in claim 115, wherein the eliminated surface layer portion
is 0.2-5 mm in depth.
117. The method for manufacturing an aluminum alloy material as
recited in claim 109, further comprising the step of performing a
secondary forming processing of a cross-sectional area decreasing
ratio of 30% or less to the shape member after the continuous
casting at a temperature of 400.degree. C. or below.
118. The method for manufacturing an aluminum alloy material as
recited in claim 117, wherein the processing temperature is
250.degree. C. or below.
119. The method for manufacturing an aluminum alloy material as
recited in claim 117, wherein the cross-sectional area decreasing
ratio is 20% or less.
Description
[0001] This application claims priority to Japanese Patent
Application No. 2001-224661filed on Jul. 25, 2001, U.S. Provisional
Patent Application No. 60/311,363 filed on Aug. 13, 2001 and
Japanese Patent Application No. 2002-148340 filed on May 22, 2002,
the disclosure of which is incorporated by reference in its
entirety.
CROSS REFERENCE TO RELATED APPLICATIONS
[0002] This application is an application filed under 35 U.S.C.
.sctn.111(a) claiming the benefit pursuant to 35
U.S.C..sctn.119(e)(1) of the filing date of U.S. Provisional Patent
Application No. 60/311,363 filed on Aug. 13, 2001, pursuant to 35
U.S.C. .sctn.111(b).
FIELD OF THE INVENTION
[0003] The present invention relates to Al--Mg--Si series aluminum
alloys excellent in cutting ability, aluminum alloy materials and
manufacturing methods thereof.
BACKGROUND ART
[0004] In cutting aluminum alloy materials, there are problems that
it is required to perform steps of disposing chips which is long
and continuous and removing burrs generated at a corner of a
product at the time of lathing or burrs generated at around a
drilled hole at the time of drilling.
[0005] In order to solve these problems, an easy-to-cut aluminum
alloy capable of suppressing cutting ability and burr generation by
adding low fusing point elements such as Pb, Bi and Sn to enhance
chip fractionizing nature, is proposed.
[0006] However, these low fusing point elements are often
segregated at a crystal grain boundary. As a result, these elements
tend to be partially fused by heat generated during, for example,
heavy machining processing, which in turn results in crack
generation. Furthermore, manufacturing and using such easy-to-cut
aluminum alloy materials containing Pb that is a toxic element
causes a serious problem from a viewpoint of earth environmental
protection and also deteriorates recycling of aluminum
products.
[0007] Accordingly, an easy-to-cut aluminum alloy containing Si or
Cu as an alternative element of the aforementioned low fusing point
element is developed.
[0008] For example, Japanese Unexamined Laid-open Patent
Publication No. H11-12705 discloses an aluminum alloy to be forged
containing Si: 3-11 mass %, Japanese Unexamined Laid-open Patent
Publication No. H9-249931 discloses a high corrosion resistant
aluminum alloy containing Si: 1.5-12.0 mass %, and Japanese
Unexamined Laid-open Patent Publication No. H2-97638 discloses an
aluminum alloy for magnetic tape contact component use containing
Si: 2.0-12.5 mass % and Cu: 1.0-6.5 mass %. In these aluminum alloy
materials, hard Si particles are dispersed in the aluminum matrix
so that the Si particles can be ground at the time of cutting or
the Si particles and the matrix interface thereof can be exfoliated
to thereby break the chips into small pieces. Since these aluminum
alloy materials do not contain low fusing point elements, they are
excellent in recycling nature, and also excellent in corrosion
resistance and heat resistance.
[0009] Furthermore, these aluminum alloy materials are manufactured
by homogenizing a cast extruding billet of predetermined
compositions, then extruding the billet at 400-600.degree. C., into
an extruded article at 350-550.degree. C., and then quenching the
extruded article at a die exit or performing a solution treatment
after cutting the extruded article into a long cut article of 1-5 m
length.
[0010] In the aforementioned conventional easy-to-cut aluminum
alloy, however, if the alloy contains 5% or more of Si, since a
large amount of Si particles are dispersed therein, there is a
drawback that the Si particles having acute-angle portions attack a
cutting edge of a cutting tool, and therefore the cutting tool will
be heavily worn down or the cutting tool will be damaged, thereby
shortening the life. On the other hand, in an aluminum alloy
containing a large amount of Cu, there is a drawback that the alloy
is poor in corrosion resistance.
[0011] Furthermore, in the aforementioned manufacturing process,
although the Si particle may sometimes become 1 .mu.m or less at
the time of casting the billet, the particle tends to grow up to a
size exceeding 1 .mu.m due to a heat treatment of 300.degree. C. or
more, which is performed after the casting. Accordingly, the Si
particle grows during each processing, i.e., homogenizing
processing, extruding processing, quenching processing at a die
exit and solution treatment processing, and finally grows up to a
size of 5-10 .mu.m. As a result, the alloy material obtained by
performing the aforementioned series of processing is poor in
cutting ability as compared to a cast member, which causes heavy
abrasion or damage of a cutting tool. Concretely, if large Si
particles with a mean particle diameter exceeding 5 .mu.m exist in
the aluminum matrix, tool damage such as tool abrasion or tool
chipping will become serious. Furthermore, the tool damage
deteriorates the quality of the machined surface obtained by a long
and continuous cutting processing. Furthermore, if alumite
processing is executed to the aluminum alloy materials containing
such large and rough Si particles, there is a problem that the
alumite coating thickness becomes uneven since the generation rate
of alumite coat differs between the Si particles exposed to the
surface and the aluminum matrix.
SUMMARY OF THE INVENTION
[0012] In view of the aforementioned technical background, the
present invention aims to provide aluminum alloys excellent in
cutting ability, capable of suppressing abrasion and damage such as
chipping of a cutting tool and having better alumite
processability, aluminum alloy materials and manufacturing methods
thereof.
[0013] The present invention includes aluminum alloys roughly
classified by chemical composition into four types, aluminum alloy
materials each having metal texture corresponding to each chemical
composition, and methods for manufacturing these aluminum alloy
materials.
[0014] A first aluminum alloy comprises Mg: 0.3-6 mass %, Si:
0.3-10 mass %, Zn: 0.05-1 mass %, Sr: 0.001-0.3 mass %, and the
balance being aluminum and impurities.
[0015] In the first aluminum alloy, it is preferable that the
content of Mg is 0.5-1.1 mass %. It is preferable that the content
of Si is 1.5-5 mass %. It is preferable that the content of Zn is
0.1-0.3 mass %. It is preferable that the content of Sr is
0.005-0.05 mass %.
[0016] A second aluminum alloy comprises Mg: 0.3-6 mass %, Si:
0.3-10 mass %, Zn: 0.05-1 mass %, Sr: 0.001-0.3 mass %, one or more
of selective additional elements selected from the group consisting
of Cu: 0.01% or more but less than 1 mass %, Fe: 0.01-1 mass %, Mn:
0.01-1 mass %, Cr: 0.01-1 mass %, Zr: 0.01-1 mass %, Ti: 0.01-1
mass %, Na: 0.001-0.5 mass %, Ca: 0.001-0.5 mass %; and the balance
being Aluminum and impurities.
[0017] In the second aluminum alloy, it is preferable that the
content of Mg is 0.5-1.1 mass %. It is preferable that the content
of Si is 1.5-5 mass %. It is preferable that the content of Zn is
0.1-0.3 mass %. It is preferable that the content of Sr is
0.005-0.05 mass %.
[0018] In the second aluminum alloy, it is preferable that the
selective additional element is Cu. It is preferable that the
selective additional element is Fe. It is preferable that the
selective additional element is one or more elements selected from
the group consisting Cr and Mn. It is preferable that the selective
additional element is Zr. It is preferable that the selective
additional element is Ti. It is preferable that the selective
additional element is one or more elements selected from the group
consisting of Na and Ca.
[0019] Furthermore, in the second aluminum alloy, it is preferable
that the content of Cu is 0.1-0.3 mass %. It is preferable that the
content of Fe is 0.1-0.3 mass %. It is preferable that the content
of Mn is 0.1-0.3 mass %. It is preferable that the content of Cr is
0.1-0.3 mass %. It is preferable that the content of Zr is 0.1-0.3
mass %. It is preferable that the content of Ti is 0.1-0.3 mass %.
It is preferable that the content of Na is 0.005-0.3 mass %. It is
preferable that the content of Ca is 0.005-0.3 mass %.
[0020] A first aluminum alloy material according to the present
invention is an aluminum alloy material having chemical composition
as recited in claim 1. That is, an aluminum alloy material composed
of an aluminum alloy, wherein the aluminum alloy comprises Mg:
0.3-6 mass %, Si: 0.3-10 mass %, Zn: 0.05-1 mass %, Sr: 0.001-0.3
mass %, and the balance being aluminum and impurities, as a
chemical composition thereof, and wherein a mean particle diameter
of Si particle is 1-5 .mu.m and a mean aspect ratio of Si particle
is 1-3, as an alloy texture of the aluminum alloy.
[0021] In this aluminum alloy material, it is preferable that the
mean particle diameter of the Si particle is 3 .mu.m or less. The
mean aspect ratio of the Si particle is preferably 2 or less.
[0022] A second aluminum alloy material according to the present
invention is an aluminum alloy material having chemical composition
as recited in claim 2. That is, an aluminum alloy material is
composed of an aluminum alloy, wherein the aluminum alloy comprises
Mg: 0.3-6 mass %, Si: 0.3-10 mass %, Zn: 0.05-1 mass %, Sr:
0.001-0.3 mass %, and the balance being aluminum and impurities, as
a chemical composition thereof, and wherein a mean particle
diameter of Si particle is 1-5 .mu.m and a mean aspect ratio of Si
particle is 1-3, as an alloy texture of the aluminum alloy.
[0023] One of the aluminum alloy materials according to the present
invention is composed of the first or second aluminum alloy in
chemical composition, i.e., any one of aluminum alloys as recited
in claims 1-24, and a mean particle diameter of Si particle is 1-5
.mu.m and a mean aspect ratio of Si particle is 1-3, as an alloy
texture of the aluminum alloy.
[0024] In the above aluminum materials, it is preferable that the
mean particle diameter of the Si particle is 3 .mu.m or less. The
mean aspect ratio of the Si particle is preferably 2 or less.
[0025] A method for manufacturing the first aluminum alloy material
is a method for suitably used to manufacture the first aluminum
alloy material. That is, a method for manufacturing an aluminum
alloy material, comprises: making a billet at a casting rate of
10-180 mm/min., the billet composed of aluminum alloy comprising
Mg: 0.3-6 mass %, Si: 0.3-10 mass %, Zn: 0.05-1 mass %, and Sr:
0.001-0.3 mass %, and the balance being aluminum and impurities;
homogenizing the billet at 400-570.degree. C. for 6 hours or more
to obtain a homogenized billet; extruding the homogenized billet at
a billet temperature of 300-550.degree. C., an extrusion rate of
0.5-100 m/min. and an extrusion ratio of 10-200 into an extruded
article having a predetermined configuration; executing a solution
treatment to the extruded article at 400-570.degree. C. for 1 hour
or more; and aging the solution treated extruded article at
90-300.degree. C. for 1-30 hours.
[0026] In the aforementioned aluminum alloy material manufacturing
method, it is preferable that the casting rate is 30-130 mm/min.
The homogenization is preferably performed at 500-545.degree. C.
for 10 hours or more. The extrusion is preferably performed at the
billet temperature of 350-500.degree. C., the extrusion rate of
2-30 m/min. and the extrusion ratio of 20-85. The solution
treatment is preferably performed at 500-545.degree. C. for 3 hours
or more. The aging is preferably performed at 140-200.degree. C.
for 3-20 hours. It is preferable that the solution treated extruded
article is drawn at a reduction rate of 5-30% into a predetermined
configuration, and thereafter the aging is performed. Especially,
the reduction rate of the drawing is preferably 10-20%.
[0027] A method for manufacturing the second aluminum alloy
material is a method for suitably used to manufacture the second
aluminum alloy material. That is, a method for manufacturing an
aluminum alloy material, comprises: making a billet at a casting
rate of 10-180 mm/min., the billet composed of aluminum alloy
comprising Mg: 0.3-6 mass %, Si: 0.3-10 mass %, Zn: 0.05-1 mass %,
and Sr: 0.001-0.3 mass %, one or more selective additional elements
selected from the group consisting of Cu: 0.01 mass % or more but
less than 1 mass %, Fe: 0.01-1 mass %, Mn: 0.01-1 mass %, Cr:
0.01-1 mass %, Zr: 0.01-1 mass %, Ti: 0.01-1 mass %, Na: 0.001-0.5
mass %, Ca: 0.001-0.5 mass %, and the balance being aluminum and
impurities; homogenizing the billet at 400-570.degree. C. for 6
hours or more to obtain a homogenized billet; extruding the
homogenized billet at a billet temperature of 300-550.degree. C.,
an extrusion rate of 0.5-100 m/min., and an extrusion ratio of
10-200 into an extruded article having a predetermined
configuration; executing a solution treatment to the extruded
article at 400-570.degree. C. for 1 hour or more; and aging the
solution treated extruded article at 90-300.degree. C. for 1-30
hours.
[0028] In the aforementioned method for manufacturing an aluminum
alloy material, it is preferable that the casting rate is 30-130
mm/min. The homogenization is preferable performed at
500-545.degree. C. for 10 hours or more. The extrusion is
preferably performed at the billet temperature of 350-500.degree.
C., the extrusion rate of 2-30 m/min. and the extrusion ratio of
20-85. The solution treatment is preferably performed at
500-545.degree. C. for 3 hours or more. The aging is preferably
performed at 140-200.degree. C. for 3-20 hours. It is preferable
that the solution treated extruded article is drawn at a reduction
rate of 5-30% into a predetermined configuration, and thereafter
the aging is performed. Especially, it is preferable that the
reduction rate of the drawing is 10-20%.
[0029] A third aluminum alloy comprises: Mg: 0.1-6 mass %; Si:
0.3-12.5 mass %; Cu: 0.01 mass % or more but less than 1 mass %;
Zn: 0.01-3 mass %; Sr: 0.001-0.5 mass %; and the balance being
aluminum and impurities.
[0030] In the third aluminum alloy, it is preferable that the
content of Mg is 0.3-5 mass %. The content of Si is preferably
0.8-12 mass %. The content of Cu is preferably 0.1-0.8 mass %. The
content of Zn is preferably 0.05-1.5 mass %. The content of Sr is
preferably 0.005-0.3 mass %.
[0031] A fourth aluminum alloy comprises: Mg: 0.1-6 mass %; Si:
0.3-12.5 mass %; Cu: 0.01 mass % or more but less than 1 mass %;
Zn: 0.01-3 mass %; Sr: 0.001-0.5 mass %; one or more of selective
additional elements selected from the group consisting of Ti:
0.001-1 mass %, B: 0.0001-0.03 mass %, C: 0.0001-0.5 mass %, Fe:
0.01 -1 mass %, Cr: 0.01-1 mass %, Mn: 0.01-1 mass %; Zr: 0.01-1
mass %, V: 0.01-1 mass %, Sc: 0.0001-0.5 mass %, Ni: 0.005-1 mass
%, Na: 0.001-0.5 mass %, Sb: 0.001-0.5 mass %, Ca: 0.001-0.5 mass
%, Sn: 0.01-1 mass %, Bi: 0.01-1 mass %, In: 0.001-0.5 mass %; and
the balance being Aluminum and impurities.
[0032] In the fourth aluminum alloy, it is preferable that the
content of Mg is 0.3-5 mass %. The content of Si is preferably
0.8-12 mass %. The content of Cu is preferably 0.1-0.8 mass %. The
content of Zn is preferably 0.05-1.5 mass %. The content of Sr is
preferably 0.005-0.3 mass %.
[0033] In the fourth aluminum alloy, it is preferable that the
selective additional element is one or more elements selected from
the group consisting of Ti, B, C and Sr. The selective additional
element is preferably Fe. The selective additional element is
preferably one or more elements selected from the group consisting
Cr and Mn. The selective additional element is preferably one or
more elements selected from the group consisting Zr and V. The
selective additional element is preferably Ni. The selective
additional element is preferably one or more elements selected from
the group consisting Na, Sb and Ca. The selective additional
element is preferably one or more elements selected from the group
consisting Sn, Bi and In.
[0034] In the fourth aluminum alloy, it is preferable that the
content of Ti is 0.003-0.5 mass %. The content of B is preferably
0.0005-0.01 mass %. The content of C is preferably 0.001-0.3 mass
%. The content of Fe is preferably 0.05-0.7 mass %. The content of
Cr is preferably 0.03-0.7 mass %. The content of Mn is preferably
0.03-0.7 mass %. The content of Zr is preferably 0.03-0.7 mass %.
The content of V is preferably 0.03-0.7 mass %. The content of Sc
is preferably 0.01-0.3 mass %. The content of Ni is preferably
0.03-0.7 mass %. The content of Na is preferably 0.005-0.3mass %.
The content of Sb is preferably 0.005-0.3mass %. The content of Ca
is preferably 0.005-0.3 mass %. The content of Sn is preferably
0.05-0.5 mass %. The content of Bi is preferably 0.05-0.5 mass %.
The content of In is preferably 0.01-0.3 mass %.
[0035] A third aluminum alloy material according to the present
invention is an alloy material having chemical composition of the
third aluminum alloy. That is, an aluminum alloy material composed
of aluminum alloy is composed of an aluminum alloy comprising Mg:
0.1-6 mass %, Si: 0.3-12.5 mass %, Cu: 0.01 mass % or more but less
than 1 mass %, Zn: 0.01-3 mass %, Sr: 0.001-0.5 mass %, and the
balance being aluminum and impurities, wherein, in metal texture, a
mean dendrite arm spacing is 1-200 .mu.m, a dendrite boundary zone
includes eutectic Si particles of 0.01-5 .mu.m of mean particle
diameters and other second phase particles, and an eutectic lamella
texture in which a mean skeleton line length (Lm) in a longitudinal
direction is 0.5 .mu.m or more and a mean width (Wm) is 0.5 .mu.m
or more is formed in a shape of a network.
[0036] In the aluminum alloy material, it is preferable that, in
the eutectic lamella texture, the eutectic Si particles and other
second phase particles exist 500 pieces/mm.sup.2 or more in total,
and the area share of these particles is 0.1-50%. The mean dendrite
arm spacing is preferably 3-100 .mu.m. The mean particle diameter
of the eutectic Si particle is preferably 0.1-3 .mu.m. Preferably,
the eutectic lamella texture has a mean skeleton line length (Lm)
of 3 .mu.m or more and a mean width (Wm) of 1 .mu.m or more. The
mean ratio (L/Wm) of the skeleton line length to the skeleton width
in the eutectic lamella texture is preferably 3 or more.
[0037] Furthermore, it is preferable that the eutectic Si particles
and other second phase particles exist 1,000 pieces/mm.sup.2 or
more in total. The area share of the eutectic Si particles and
other second phase particles is preferably 0.3-40%.
[0038] A fourth aluminum alloy material according to the present
invention is an alloy material having chemical composition of the
third aluminum alloy. That is, an aluminum alloy material is
composed of an aluminum alloy, wherein the aluminum alloy comprises
Mg: 0.1-6 mass %; Si: 0.3-12.5 mass %; Cu: 0.01 mass % or more but
less than 1 mass %; Zn: 0.01-3 mass %; Sr: 0.001-0.5 mass %; one or
more of selective additional elements selected from the group
consisting of Ti: 0.001-1 mass %, B:0.0001-0.03 mass %, C:
0.0001-0.5 mass %, Fe: 0.01-1 mass %, Cr: 0.01-1 mass %, Mn: 0.01-1
mass %, Zr: 0.01-1 mass %, V: 0.01-1 mass %, Sc: 0.0001-0.5 mass %,
Ni: 0.005-1 mass %, Na: 0.001-0.5 mass %, Sb: 0.001-0.5 mass %, Ca:
0.001-0.5 mass %, Sn: 0.01-1 mass %, Bi: 0.01-1 mass %, In:
0.001-0.5 mass %; and the balance being Aluminum and impurities,
and wherein, in metal texture, a mean dendrite arm spacing is 1-200
.mu.m, a dendrite boundary zone includes eutectic Si particles of
0.01-5 .mu.m of mean particle diameter and other second phase
particles, and an eutectic lamella texture in which a mean skeleton
line length (Lm) in a longitudinal direction is 0.5 .mu.m or more
and a mean width (Wm) is 0.5 .mu.m or more is formed in a shape of
a network.
[0039] In the aforementioned aluminum alloy material, in the
eutectic lamella texture, the eutectic Si particles and other
second phase particles exist 500 pieces/mm.sup.2 or more in total,
and the area share of these particles is 0.1-50%. The mean dendrite
arm spacing is preferably 3-100 .mu.m. The mean particle diameter
of the eutectic Si particle is preferably 0.1-3 .mu.m. Preferably,
the eutectic lamella texture has a mean skeleton line length (Lm)
of 3 .mu.m or more and a mean width (Wm) of 1 .mu.m or more. The
mean ratio (L/Wm) of the skeleton line length to the skeleton width
in the eutectic lamella texture is preferably 3 or more.
[0040] Furthermore, it is preferable that the eutectic Si particles
and other second phase particles exist 1,000 pieces/mm.sup.2 or
more in total. The area share of the eutectic Si particles and
other second phase particles is preferably 0.3-40%.
[0041] A method for manufacturing the third aluminum alloy material
is a method for suitably used to manufacture the third aluminum
alloy material. That is, a method for manufacturing an aluminum
alloy material, the method comprises: continuously casting molten
aluminum alloy to obtain a shape member having a prescribed cross
section at a casting rate of 30-5000 mm/min. and a cooling rate of
10-600.degree. C./sec., the molten aluminum alloy comprising Mg:
0.1-6 mass %, Si: 0.3-12.5 mass %, Cu: 0.01 mass % or more but less
than 1 mass %, Zn: 0.01-3 mass %, Sr: 0.001-0.5 mass % and the
balance being aluminum and impurities and held at the solidus
temperature or more; thereafter aging the shape member at
100-300.degree. C. for 0.5-100 hours.
[0042] In the aforementioned method for manufacturing an aluminum
alloy material, it is preferable that the casting rate is 100-2000
mm/min. The cooling rate is preferably 30-300.degree. C./sec. The
aging is preferably performed at 120-220.degree. C. for 1-30 hours.
Preferably, the shape member is a non-hollow member. It is
preferable that the shape member circumscribes to a circle with a
diameter of 10-150 mm in cross section. It is preferable that the
method further comprises a step of removing a surface layer portion
of a 0.1-10 mm depth from the continuously cast shape member. The
removed surface layer portion is preferably 0.2-5 mm in depth.
[0043] It is preferable that the method further comprises the step
of performing a secondary forming processing of a cross-sectional
area decreasing ratio of 30% or less to the shape member after the
continuous casting at a temperature of 400.degree. C. or below. The
processing temperature is preferably 250.degree. C. or below. The
cross-sectional area decreasing ratio is preferably 20% or
less.
[0044] A method for manufacturing the fourth aluminum alloy
material is a method for suitably used to manufacture the fourth
aluminum alloy material. That is, a method for manufacturing an
aluminum alloy material, comprises: continuously casting molten
aluminum alloy to obtain a shape member having a prescribed cross
section at a casting rate of 30-5,000 mm/min. and a cooling rate of
10-600.degree. C./sec., the molten aluminum alloy comprising Mg:
0.1-6 mass %, Si: 0.3-12.5 mass %, Cu: 0.01 mass % or more but less
than 1 mass %, Zn: 0.01-3 mass %, Sr: 0.001-0.5 mass %, one or more
of selective additional elements selected from the group consisting
of Ti: 0.001-1 mass %, B: 0.0001-0.03 mass %, C: 0.0001-0.5 mass %,
Fe: 0.01-1 mass %; Cr: 0.01-1 mass %, Mn: 0.01-1 mass %, Zr: 0.01-1
mass %, V: 0.01-1 mass %, Sc: 0.0001-0.5 mass %, Ni: 0.005-1 mass
%, Na: 0.001-0.5 mass %, Sb: 0.001-0.5 mass %, Ca: 0.001-0.5 mass
%, Sn: 0.01-1 mass %, Bi: 0.01-1 mass %, In: 0.001-0.5 mass %, and
the balance being aluminum and impurities and held at the solidus
temperature or more; thereafter aging the shape member at
100-300.degree. C. for 0.5-100 hours.
[0045] In the aforementioned method for manufacturing an aluminum
alloy material, it is preferable that the casting rate is 100-2,000
mm/min. The cooling rate is 30-300.degree. C./sec. The aging is
preferably performed at 120-220.degree. C. for 1-30 hours.
Preferably, the shape member is a non-hollow member. It is
preferable that the shape member circumscribes to a circle with a
diameter of 10-150 mm in cross section. It is preferable that the
method further comprises a step of removing a surface layer portion
of a 0.1-10 mm depth from the continuously cast shape member.
Preferably, the removed surface layer portion is 0.2-5 mm in
depth.
[0046] Furthermore, it is preferable that the method further
comprises the step of performing a secondary forming processing of
a cross-sectional area decreasing ratio of 30% or less to the shape
member after the continuous casting at a temperature of 400.degree.
C. or below. The processing temperature is preferably 250.degree.
C. or below. Furthermore, the cross-sectional area decreasing ratio
is preferably 20% or less.
[0047] In the following explanation, the aforementioned four types
of first to fourth aluminum alloys will be detailed by classifying
them into the first and second aluminum alloys containing Mg, Si,
Zn and Sr as common indispensable elements and the third and fourth
aluminum alloys containing Mg, Si, Cu, Zn and Sr as common
indispensable elements. Following the explanation of each aluminum
alloy composition, the aluminum alloy materials and the
manufacturing methods thereof corresponding to these compositions
will be explained.
[0048] I. The First and Second Aluminum Alloys, Alloy Materials,
and the Manufacturing Methods (claims 1-46)
[0049] The first and second aluminum alloys and the alloy materials
having the chemical compositions thereof suppress abrasion and
damage of a cutting tool by rounding and fining Si particles while
securing good cutting ability caused by the enhanced chip breakable
nature due to the Si particles. Furthermore, in addition to the
strengthening by the main deposit, Mg.sub.2Si, the strength of the
alloys are notably improved by the excessive Si particles, as
compared to conventional alloys.
[0050] Hereinafter, the reasons for adding each element and for
limiting the amount of each element in the aluminum alloys and the
alloy materials will be detailed.
[0051] In the composition of the aforementioned aluminum alloy,
four elements of Mg, Si, Zn and Sr are essential elements. The
first aluminum alloy (claims 1-5) according to the present
invention comprises these 4 elements and the balance being aluminum
and impurities.
[0052] Mg is dissolved in an alloy matrix and dispersed as deposits
such as Mg.sub.2Si created by bonding with excessive Si, etc in the
matrix, to thereby enhance the mechanical property, especially
proof strength and further improve the cutting ability of the alloy
by the synergistic effect with other solid solution type elements.
If the Mg content is less than 0.3 mass %, the aforementioned
effects cannot be obtained sufficiently. To the contrary, if the Mg
content exceeds 6.0 mass %, oxidation of an alloy molten metal is
promoted and plastic-working nature deteriorates. Accordingly, the
Mg content should be 0.3-6 mass %. Preferably, the Mg content is
0.5-1.1 mass %.
[0053] Since only few amount of Si can be dissolved in an aluminum,
Si is dispersed in the matrix as a single particle of Si except for
the amount required for compound formation. In the alloy texture in
which Si particles are dispersed, since the Si particles are ground
by a cutting tool and/or the Si particle and the aluminum base
phase are peeled at the interface, the chips can be easily broken,
resulting in improved cutting ability. Furthermore, the Si
particles become round and fine by Sr added as an essential
element, or Na, Ca added as an arbitrary element, which also
improves the cutting ability. If Si content is less than 0.3 mass
%, sufficient chip breaking effects cannot be obtained. To the
contrary, if Si content exceeds 10 mass %, although the chip
breaking effects can be improved, a cutting tool will be abraded
heavily, causing deteriorated productivity. Accordingly, it is
necessary that Si content is 0.3-10 mass %. From this point of
view, the preferable Si content is 1.5-5 mass %.
[0054] Zn dissolves in an alloy matrix, while Zn bonds with Mg and
disperses in a matrix as deposit of MgZn.sub.2. This improves the
mechanical property of the aluminum alloy and the cutting ability
of the alloy by the synergistic effects of other dissolve type
elements. If Zn content is less than 0.05 mass %, the
aforementioned effects cannot be obtained sufficiently. To the
contrary, if Zn content exceeds 1 mass %, the corrosion resistance
may deteriorate. Accordingly, it is necessary that Zn content is
0.05-1 mass %. Furthermore, if the Zn content falls within the
range, it is effective in improving an alumite coat generation
rate, and therefore the alloy can be suitably used for a product to
which alumite processing is performed for the purpose of improving
the abrasion resistance. The preferable Zn content is 0.1-0.3 mass
%.
[0055] Sr makes eutectic Si at the time of solidification and
proeutectic Si round and fine when Sr coexists with Si. This
indirectly improves the chip breaking nature, which in turn
improves the cutting ability and suppresses abrasion and damage on
a cutting tool. Furthermore, Sr has effects of making Si particles
disperse uniformly and finely at the steps of continuous casting,
extrusion, drawing, etc., thereby further improving the cutting
ability. If Sr content is less than 0.001 mass %, the
aforementioned effects cannot be obtained sufficiently and the Si
particle cannot be rounded, causing acute portions, which results
in heavy abrasion of a cutting tool. To the contrary, if Sr exceeds
0.3 mass %, the aforementioned effects will be saturated, resulting
in fruitless addition. Accordingly, Sr should be 0.001-0.3 mass %.
Preferably, the Sr content is 0.005-0.05 mass %.
[0056] The second aluminum alloy according to the present invention
(claims 6-24) is an aluminum alloy containing the aforementioned
four essential elements as basic compositions and further
containing one or more arbitrary combined elements selected from
the group consisting of eight elements, Cu, Fe, Mn, Cr, Zr, Ti, Na
and Ca for the purpose of further improving various characteristics
of the alloy.
[0057] Cu dissolves in an alloy matrix, while Cu bonds with Al and
disperses in a matrix as deposit of CuAl.sub.2. This improves the
mechanical property and cutting ability of an aluminum alloy by the
synergistic effects with other dissolve type elements. If Cu
content is less than 0.01 mass %, the aforementioned effects cannot
be obtained sufficiently. To the contrary, if Cu content exceeds 1
mass %, there is a possibility that corrosion resistance
deteriorates. Accordingly, it is preferable that Cu content is 0.01
or more but less than 1 mass %. More preferably, the Cu content is
0.1-0.3 mass %.
[0058] Fe is an inevitable element contained in an aluminum alloy.
The content falling within the range of 0.01-1 mass % is a normal
amount contained during manufacturing an aluminum alloy. Therefore,
no special step for decreasing Fe content is required. Furthermore,
if Fe content falls within the aforementioned range, since only a
few amount of Fe bonds with Si, Si, which is effective to improve
chip breaking effect, can be distributed as an individual particle,
which can maintain outstanding chip breaking nature. In order to
decrease the Fe content less than 0.01 mass %, the cost increases.
To the contrary, if Fe content exceeds 1 mass %, Fe compounds with
Si increase and Si individual particles decrease, resulting in
deteriorated chip breaking nature. It is preferable that Fe content
is 0.1-0.3 mass %.
[0059] Mn and Cr are elements to be added in order to improve
mechanical strength by suppressing recrystallization in an aluminum
alloy and enhance corrosion resistance. If Mn content and Cr
content is less than 0.01 mass % respectively, it is difficult to
obtain sufficient recrystallization inhibition effect and improve
mechanical property and corrosion resistance. Furthermore, the chip
breaking nature in the cross-sectional direction becomes unstable
because of the recrystallized large particles. To the contrary, if
the content exceeds 1 mass %, the hot deformation resistance at the
time of extrusion increases, resulting in deteriorated
productivity. Therefore, it is preferable that Mn content and Cr
content are 0.01-1mass % respectively. Furthermore, if Mn and Cr
content falls within the aforementioned range, since only a few
amount thereof bonds with Si, Si, which is effective in improving
chip breaking effect, can be distributed as an individual particle,
which can maintain outstanding chip breaking nature. More
preferable Mn content and Cr content are 0.1-0.3 mass %,
respectively.
[0060] Zr is an elements to be added in order to improve mechanical
strength by suppressing generation of large particle due to
recrystallization in an aluminum alloy and enhance corrosion
resistance. Furthermore, intermetallic compounds are formed by Zr
and Al, and dispersed in a matrix. This improves cutting ability.
If Zr content is less than 0.01 mass %, it is difficult to obtain
sufficient recrystallization inhibition effect and improve
mechanical property and corrosion resistance. Furthermore, the chip
breaking nature in the cross-sectional direction becomes unstable
because of the recrystallized large particles, and the cutting
improvement effect is poor. To the contrary, if the content exceeds
1 mass %, the extrusion nature and/or castability deteriorates
remarkably. Therefore, it is preferable that Zr content is 0.01-1
mass %. From this view point, more preferable Zr content is 0.1-0.3
mass %.
[0061] Ti is, similar to Zr, an elements to be added in order to
improve mechanical strength by suppressing generation of large
particle due to recrystallization in an aluminum alloy and enhance
corrosion resistance. If Ti content is less than 0.01 mass %, it is
difficult to obtain sufficient recrystallization inhibition effect
and improve mechanical property and corrosion resistance.
Furthermore, the chip breaking nature in the cross-sectional
direction becomes unstable because of the recrystallized large
particles, and the cutting improvement effect is poor. To the
contrary, if the content exceeds 1 mass %, the extrusion nature
and/or castability deteriorates remarkably. Therefore, it is
preferable that Ti content is 0.01-1 mass %. From this view point,
more preferable Ti content is 0.1-0.3 mass %.
[0062] Na and Ca are elements to be added, similar to the
aforementioned Sr, in order to round Si particle and disperse Si
particles uniformly. If Na content is less than 0.001 mass %, the
aforementioned effects cannot be obtained sufficiently. To the
contrary, if Na content exceeds 0.5 mass %, the effects will be
saturated. Accordingly, it is preferable that Na content is
0.001-0.5 mass %. If Ca content is less than 0.001 mass %, the
aforementioned effects cannot be obtained sufficiently. To the
contrary, if Ca content exceeds 0.5 mass %, the effects will be
saturated. Accordingly, it is preferable that Ca content is
0.001-0.5 mass %. More preferably, Na content is 0.005-0.3 mass %,
Ca content is 0.005-0.3 mass %.
[0063] In the aluminum alloy and alloy material according to the
present invention, since Sr, which is effective in rounding Si
individual particle and dispersing Si particles uniformly, is
contained as an essential element, an addition of Na and Ca is
arbitrary. Therefore even if these elements are not added, the
rounding of Si particle and uniform dispersibility of Si particles
are secured.
[0064] As for the aforementioned eight elements to be arbitrarily
selected, the aforementioned effects can be obtained by adding at
least one element or two or more arbitrarily combined elements to
the essential four elements. The aluminum alloys as recited in
claims 11-16 include selective additional element(s) in order to
obtain a predetermined effect. In cases where two or more elements
are added, it is also preferable to selectively combine two or more
elements different in effect. For example, these selective
additional elements are classified into: A group element (Cu) which
improves mechanical property by deposit such as CuAl.sub.2; B group
element (Fe) which distributes Si as individual particles; C group
element (Cr, Mn) which improves mechanical strength by suppressing
recrystallization; D group element (Ti) which improves mechanical
strength by suppressing generation of large and rough particles due
to recrystallization and also improves corrosion resistance; E
group element (Zr) which improves mechanical strength by
suppressing generation of large and rough particles due to
recrystallization, improves corrosion resistance and also improves
cutting ability by forming intermetallic compounds; and F group
elements (Na, Ca) which are effective in rounding Si particle and
making Si particle into small pieces. Then, one or two or more
arbitrarily combined groups are added to the essential elements. As
for the group comprising plural elements, one or more elements are
arbitrarily selected within the group. In cases where arbitrary
additional elements are selected per one group, the content of each
element should fall within the aforementioned range.
[0065] The first and the second aluminum alloy materials (claims
25-27 and claims 28-30) defines the chemical compositions of an
alloy falling within the range of the aforementioned first and the
second aluminum alloys (claims 1 and 6 respectively) and the mean
particle diameter and mean aspect ratio of Si particle in an alloy
texture.
[0066] Although Si particles improve cutting ability by serving as
chip breaking origins at the time of cutting, it is required that
Si particle is fine and spherical in order to suppress abrasion of
a tool and that the mean particle diameter is 1-5 .mu.m and the
mean aspect ratio is 1-3. Si particle has a tendency that the mean
particle diameter and the mean aspect ratio become larger as the Si
content increases. Although good cutting ability can be obtained
even if the mean particle diameter exceeds 5 .mu.m, a tool will be
abraded heavily if the mean aspect ratio becomes larger.
Accordingly, in this invention, in order to realize both good
cutting ability and suppressed abrasion of a tool, the mean
particle diameter and mean aspect ratio of Si particle are
specified within the aforementioned range. From the viewpoint of
obtaining outstanding cutting ability and suppressing abrasion of a
tool, the preferable mean particle diameter of Si particle is 3
.mu.m or less, and the preferable mean aspect ratio is two or
less.
[0067] The first and second aluminum alloys mentioned above can be
manufactured by the method for manufacturing the first and second
aluminum alloy materials respectively (claims 31-38, claims 39-46).
That is, the alloy material in which fined and rounded Si particles
are distributed uniformly can be manufactured by using an alloy
having predetermined chemical compositions and specifying the
processing conditions of from a casting and extrusion of a billet
to a drawing of the extruded article and heat treatment
conditions.
[0068] A billet is formed at the casting rate of 10-180 mm/min.
During this casting, the Si--Sr compound in a molten metal serves
as a nucleus, and rounded proeutectic Si and eutectic Si are
dispersed in the aluminum. As a result, fined and rounded Si
particles can be obtained by the following heat treatment and
extruding processing, or the drawing processing. Furthermore, since
Si particles are rarely partially segregated at the crystal grain
boundary and uniformly distributed in a cross-section, stable chip
breaking nature can be obtained. If the casting rate is less than
10 mm/min., Si particle becomes larger and the particle
distribution becomes rough. Therefore, stable chip breaking nature
cannot be obtained. To the contrary, if the casting rate exceeds
180 mm/min., a casting surface may become bad or solidification
crack may occur. The preferable casting rate is 30-130 mm/min.
[0069] The homogenization processing of the billet is performed by
holding the billet at 400-570.degree. C. for 6 hours or more. Since
this homogenization processing causes stable growth of Si particles
and dissolving of other dissolve type elements, no partial
segregation at the dendrite boundary zone or the crystal grain
boundary occurs. Accordingly, the cutting ability, mechanical
property and corrosion resistance of the finally obtained alloy
material become good. If the homogenization processing performed at
less than 400.degree. C., or for less than 6 hours, Si particle
does not stably grows, and dissolve type elements are not
dispersed, and not dissolved in the aluminum. Accordingly,
corrosion resistance deteriorates at the segregated portion, and
stable chip breaking nature cannot be obtained. To the contrary, if
the temperature exceeds 570.degree. C., voids are formed in the
alloy texture by the eutectic fusion of aluminum and other each
element, causing a deterioration of mechanical property. The
preferable homogenization processing condition is to hold the
billet at 500-545.degree. C. for 10 hours or more.
[0070] The extrusion is performed at the billet temperature of
300-550.degree. C., the extrusion product rate of 0.5-100 m/min.
and the extrusion ratio of 10-200. By performing the extrusion
under the conditions, Si particles will be dispersed uniformly at
the crystal grain boundary without causing partial segregation,
which does not spoil the cutting ability, mechanical property and
corrosion resistance of the finally obtained alloy material.
Furthermore, the productivity will be also good. If the billet
temperature is less than 300.degree. C., the extrusion rate will
deteriorate, resulting in poor productivity. The productivity will
also deteriorate when the extrusion product rate is less than 0.5
m/min. Furthermore, if the extrusion ratio is less than 10, the
distributed state of Si particles will not become uniform, and Si
particles will be partially segregated at the old dendrite boundary
zone. This causes unstable cutting ability and deteriorated
mechanical property and corrosion resistance. To the contrary, if
the billet temperature exceeds 550.degree. C., the extrusion
product rate exceeds 100 m/min. or the extrusion ratio exceeds 200,
tears, pickups and the like arise on the surface of the extruded
member, resulting in deteriorated surface quality. The preferable
billet temperature is 350-500.degree. C., the preferable extrusion
product rate is 2-30 m/min., and the preferable extrusion ratio is
20-85.
[0071] The solution treatment after the extrusion is performed by
holding the billet at 400-570.degree. C. for 1 hour or more. This
solution treatment rounds Si particle, and therefore stable chip
breaking nature can be obtained. Furthermore, the solution
treatment decreases the partial segregation at the crystal grain
boundary of the additional element, and therefore high mechanical
property and high corrosion resistance can be obtained. If the
solution treatment condition is less than 400.degree. C. or less
than 1 hour, mechanical strength becomes insufficient and chip
breaking nature becomes poor. To the contrary, if the temperature
exceeds 570.degree. C., partial fusion at the crystal grain
boundary occurs, and mechanical property deteriorates remarkably.
The preferable solution treatment is performed by holding the
billet at 500-545.degree. C. at 3 hours or more.
[0072] The aging treatment is performed by holding the billet at
90-300.degree. C. for 1-30 hours. This causes the maximum strength
and good chip breaking nature of the aluminum alloy material. If
the aging temperature is less than 90.degree. C. or the holding
time is less than 1 hour, the aging becomes insufficient, the
finished surface at the time of cutting becomes rough and the
mechanical property deteriorates. To the contrary, if the aging
temperature exceeds 300.degree. C. or the aging time exceeds 30
hours, the aging becomes excessive, which deteriorates chip
breaking nature and mechanical property. The preferable aging is
performed by holding the billet at 140-200.degree. C. for 3-20
hours.
[0073] The extruded member after the solution treatment is
preferably drawn at a reduction rate of 5-30% into a predetermined
configuration. This drawing forms a predetermined configuration,
and also can improve the mechanical property by fining the
recrystallized structure of the surface formed at the time of
extrusion. Furthermore, high dimensional accuracy in the
longitudinal direction can be obtained. If the drawing reduction
rate is less than 5%, the aforementioned effect becomes poor. To
the contrary, if it exceeds 30%, tension breaks may occur at the
time of drawing. The preferable reduction is 10-20%.
[0074] Other manufacturing conditions follow those for a
conventional method.
[0075] II. The Third and Fourth Aluminum Alloys, Alloy Materials,
and the Manufacturing Methods (claims 47-119)
[0076] The third and fourth aluminum alloys and the aluminum alloy
materials including the chemical compositions thereof can further
enhance the cutting ability due to Si particles obtained by the
predetermined chemical compositions by further specifying the metal
texture, and can suppress abrasion and damage on a cutting tool by
controlling Si particle size.
[0077] Hereinafter, the reasons for adding each element and for
limiting the amount of each element in the aluminum alloys and the
alloy materials will be detailed.
[0078] In the composition of the aforementioned aluminum alloy,
five elements of Mg, Si, Cu, Zn and Sr are essential elements. The
third aluminum alloy (claims 47-52) according to the present
invention comprises these five elements and the balance being
aluminum and impurities.
[0079] Mg is dissolved in an alloy matrix and dispersed as deposits
such as Mg.sub.2Si created by bonding with Si, etc in the matrix,
to thereby enhance the mechanical property, especially proof
strength and further improve the cutting ability of the alloy by
the synergistic effect with other solid solution type elements. If
the Mg content is less than 0.1 mass %, the aforementioned effects
cannot be obtained sufficiently. To the contrary, if the Mg content
exceeds 6 mass %, oxidation of an alloy molten metal is promoted
and plastic-working nature also deteriorates. Accordingly, the Mg
content should be 0.1-6 mass %. Preferably, the Mg content is 0.3-5
mass %.
[0080] Since only a few amount of Si can be dissolved in an
aluminum, Si is dispersed in the matrix as a single particle of Si
except for the amount required for compound formation. Especially,
the eutectic Si particles solidified and formed by the quick
cooling at the time of the continuous casting of this invention
become fine particles of 5 .mu.m or less, and form eutectic lamella
texture together with other second phase particles at the dendrite
boundary zone. At the time of cutting, a cutting tool causes
separation of the eutectic lamella texture, grinding of the
eutectic Si particles, and/or interfacial peeling between the
eutectic Si particles and the aluminum host phase. As a result, the
chips become easy-to-break, which improves cutting ability
remarkably. Furthermore, the Si particles are rounded and fined by
Sr added as an essential element or Na, Ca added as an arbitrary
element, which also improves the cutting ability. If Si content is
less than 0.3 mass %, chip breaking nature, i.e., cutting ability
improving effects, cannot be obtained sufficiently. To the
contrary, if Si content exceeds 12.5 mass %, although the cutting
ability can be improved, many big and rough eutectic Si particles
are formed. Therefore, cutting tool damages such as abrasion and/or
chipping occur heavily, causing deteriorated productivity.
Accordingly, it is necessary that Si content is 0.3-12.5 mass %.
From this point of view, the preferable Si content is 0.8-12 mass
%, more preferably 1.2-8.5 mass %.
[0081] Cu dissolves in an alloy matrix, while Cu bonds with Al and
disperses in a matrix as deposit of CuAl.sub.2, etc. This improves
the mechanical property and cutting ability of an aluminum alloy by
the synergistic effects with other dissolve type elements.
Furthermore, the CuAl.sub.2 also exists in the eutectic lamella
texture, and improves cutting ability by participating the
separation of the eutectic lamella texture at the time of cutting.
If Cu content is less than 0.01 mass %, the aforementioned effects
cannot be obtained sufficiently. To the contrary, if Cu content
exceeds 1 mass %, corrosion resistance may deteriorate.
Accordingly, the Cu content is 0.01 or more but less than 1 mass %.
More preferably, the Cu content is 0.1-0.8 mass %.
[0082] Zn dissolves in an alloy matrix, while Zn bonds with Mg and
disperses in a matrix as deposit of MgZn.sub.2, etc. This improves
the mechanical property of the aluminum alloy and the cutting
ability of the alloy by the synergistic effects of other dissolve
type elements. If Zn content is less than 0.01 mass %, the
aforementioned effects cannot be obtained sufficiently. To the
contrary, if Zn content exceeds 3 mass %, there is a possibility
that corrosion resistance deteriorates. Accordingly, it is
necessary that Zn content is 0.01-3 mass %. Furthermore, if the Zn
content falls within the range, it is effective in improving an
alumite coat generation rate, and therefore the alloy can be
suitably used for a product to which alumite processing is
performed for the purpose of improving the abrasion resistance. The
preferable Zn content is 0.05-1.5 mass %.
[0083] Sr makes eutectic Si at the time of solidification and
proeutectic Si round and fine when Sr coexists with Si. This
indirectly improves the chip breaking nature, which in turn
improves the cutting ability and suppresses abrasion and damage
such as chipping on a cutting tool. Furthermore, Sr has effects of
making Si particles disperse uniformly and finely at the steps of
continuous casting and/or the following secondary forming
processing, thereby further improving the cutting ability. If Sr
content is less than 0.001 mass %, the aforementioned effects
cannot be obtained sufficiently, and the Si particle cannot be
rounded, causing acute portions, which results in heavy abrasion or
damage such as chipping of a cutting tool. To the contrary, if Sr
exceeds 0.5 mass %, the aforementioned effects will be saturated,
resulting in fruitless addition. The preferable Sr content is
0.005-0.3 mass %.
[0084] The fourth aluminum alloy according to the present invention
(claims 53-81) is an aluminum alloy containing the aforementioned
five essential elements as basic compositions and further
containing one or more arbitrary combined elements selected from
the group consisting of sixteen elements, Ti, B, C, Fe, Cr, Mn, Zr,
V, Sc, Ni, Na, Sb, Ca, Sn, Bi and In for the purpose of further
improving various characteristics of the alloy.
[0085] Ti makes an ingot texture fine, and suppresses appearance of
macro patterns and/or solidification cracks, which will be
generated on the cut surface when the ingot texture is rough. If Ti
content is less than 0.001 mass %, an ingot fining effect is poor.
To the contrary, if it exceeds 1 mass %, rough Ti-Al series
compounds will be formed, which may deteriorate castability and/or
ductility of the aluminum alloy. Accordingly, it is preferable that
Ti content is 0.001-1 mass %. The more preferable Ti content is
0.003-0.5 mass %.
[0086] B makes an ingot texture fine like Ti, and suppresses
appearance of macro patterns and/or solidification cracks, which
will be generated on the cut surface when the ingot texture is
rough. If B content is less than 0.0001 mass %, an ingot fining
effect is poor. To the contrary, if it exceeds 0.03 mass %, hard
particles will be formed, which may increase abrasion and/or
damages such as chipping. Accordingly, it is preferable that B
content is 0.0001-0.03mass %. The more preferable Ti content is
0.0005-0.01 mass %.
[0087] Fe is an element inevitably contained in an aluminum alloy.
The content falling within the range of 0.01-1 mass % is a normal
amount contained during manufacturing an aluminum alloy. Therefore,
no special step for decreasing Fe content is required. Furthermore,
if Fe content falls within the aforementioned range, since only a
few amount of Fe bonds with Si, Si, which is effective to improve
chip breaking effect, can be distributed as an individual particle,
which can maintain outstanding chip breaking nature. In order to
decrease the Fe content less than 0.01 mass %, the cost increases.
To the contrary, if Fe content exceeds 1 mass %, Fe compounds with
Si increase and Si individual particles decrease, resulting in
deteriorated chip breaking nature. The more preferable Fe content
is 0.05-0.7 mass %.
[0088] Zr and V make an ingot texture fine, and suppresses
appearance of macro patterns and/or solidification cracks, which
will be generated on the cut surface when the ingot texture is
rough, like Ti and B. Furthermore, an intermetallic compound is
formed between aluminum and cutting ability improves because they
disperse to a matrix. If the content of each element is less than
0.01 mass %, the aforementioned effect is poor. To the contrary, if
it exceeds 1 mass %, castability deteriorates. Accordingly, it is
preferable that the content of each element is 0.01-1 mass %. The
preferable content is 0.03-0.7 mass %. Furthermore, Zr has an
effect of improving mechanical strength by suppressing the
recrystallization and enhancing corrosion resistance, like
below-mentioned Cr and Mn. As for these effects, if Zr content is
less than 0.01 mass %, the mechanical property and corrosion
resistance cannot be improved, and the chip breaking nature in the
cross-sectional direction becomes unstable since large and rough
particles are formed by recrystallization. To the contrary, if it
exceeds 1 mass %, the hot deformation resistance at the time of
secondary forming processing increases, resulting in deteriorated
productivity. Accordingly, it is preferable that Zr content is
0.01-1 mass %, more preferably 0.03-0.7 mass %.
[0089] Cr and Mn are elements to be added in order to improve
mechanical strength by suppressing recrystallization in an aluminum
alloy and enhance corrosion resistance. If Cr content and Mn
content are less than 0.01 mass % respectively, it is difficult to
obtain sufficient recrystallization inhibition effect and improve
mechanical property and corrosion resistance. Furthermore, the chip
breaking nature in the cross-sectional direction becomes unstable
because of the recrystallized large particles. To the contrary, if
the content exceeds 1 mass %, the hot deformation resistance at the
time of extrusion increases, resulting in deteriorated
productivity. Therefore, it is preferable that Mn content and Cr
content are 0.01-1 mass % respectively. Furthermore, if Mn and Cr
content fall within the aforementioned range, since only a few
amount thereof bonds with Si, Si, which is effective in improving
chip breaking effect, can be distributed as an individual particle,
which can maintain outstanding chip breaking nature. More
preferable Mn content and Cr content are 0.03-0.7 mass %,
respectively.
[0090] Sc and C make an ingot texture fine, and suppresses
appearance of macro patterns and/or solidification cracks, which
will be generated on the cut surface when the ingot texture is
rough, like Zr, V, B and Ti. If these elements are less than 0.0001
mass % respectively, the aforementioned effect cannot be obtained
sufficiently. To the contrary, if they exceed 0.5 mass %
respectively, they bond with aluminum or other elements to form
hard particles, which causes heavy abrasion or damage on a cutting
tool. Accordingly, it is preferable that the contents are
0.0001-0.5 mass %. Their more preferable contents are 0.01-0.3 mass
%, respectively.
[0091] Ni forms Ni--Al series intermetallic compounds to improve
cutting ability. If Ni content is less than 0.005 mass %, the
aforementioned effect cannot be obtained sufficiently. To the
contrary, if the content exceeds 1 mass %, castability and
corrosion resistance deteriorates. Accordingly, it is preferable
that Ni content is 0.005-1 mass %, more preferably 0.03-0.7 mass
%.
[0092] Na, Sb and Ca make eutectic Si at the time of solidification
and proeutectic Si round and fine when they coexist with Si, like
Sr. This indirectly improves the chip breaking nature, which in
turn improves the cutting ability and suppresses abrasion and
damage such as chipping on a cutting tool. If the content of each
of these elements is less than 0.001 mass %, the aforementioned
effects cannot be obtained sufficiently. To the contrary, if it
exceeds 0.5 mass %, the aforementioned effects will be saturated,
resulting in fruitless addition. Accordingly, it is preferable that
each content is 0.001-0.5 mass %, more preferably 0.005-0.3 mass
%.
[0093] Sn, Bi and In further improve cutting ability when they
coexist with Si. The content thereof should be Sn: 0.01-1 mass %,
Bi: 0.01-1 mass % and In: 0.001-0.5 mass %. If each content is
below the lower limit, the aforementioned effects cannot be
obtained sufficiently. To the contrary, if it exceeds the upper
limit, the corrosion resistance deteriorates, and the quality of
the finished surface also deteriorates since tears will be
generated at the time of cutting, especially at the time of deep
cutting. Furthermore, cracks will be induced at the time of the hot
deformation. Their preferable content is Sn: 0.05-0.5 mass %, Bi:
0.05-0.5 mass %, and In: 0.01-0.3 mass %.
[0094] As for the aforementioned sixteen elements to be arbitrarily
selected, the aforementioned effects can be obtained by adding at
least one element or two or more arbitrarily combined elements to
the essential five elements. The aluminum alloys as recited in
claims 48-54 include selective additional element(s) in order to
obtain predetermined effects. In cases where two or more elements
are added, it is also preferable to selectively combine two or more
elements different in effect. For example, these selective
additional elements are classified into: A group element (Ti, B, C,
Sc) which has an effect of fining an ingot texture and suppressing
an appearance of a macro pattern and solidification cracks; B group
element (Fe) which distributes Si as individual particles; C group
element (Cr, Mn) which improves mechanical strength by suppressing
recrystallization; D group element (Zr, V) which has effects of
fining an ingot texture and of suppressing an appearance of a macro
pattern and solidification cracks, and further improves cutting
ability due to the formation of intermetallic compounds; E group
element (Ni) which improves cutting ability by forming
intermetallic compounds; F group element (Na, Sb, Ca) which has an
effect of rounding and fining Si particle; and G group element (Sn,
Bi, In) which improves cutting ability when it coexists with Si.
Then, one or two or more arbitrarily combined groups are added to
the essential elements. As for the group comprising plural
elements, one or more elements are arbitrarily selected within the
group. In cases where arbitrary additional elements are selected
per one group, the content of each element should fall within the
aforementioned range.
[0095] The third and fourth aluminum alloy materials (claims 82-89
and claims 90-97) define the chemical compositions of an alloy so
as to fall within the range of the aforementioned third and fourth
aluminum alloys (claims 47 and 53), and specify the metal
texture.
[0096] FIGS. 1 and 2 show an example of metal texture of an
aluminum alloy material manufactured by casting according to the
present invention. FIG. 3 shows an example of metal texture of an
aluminum alloy material manufactured by performing processing such
as heat treatment and extrusion after casting. The aluminum alloy
material shown in FIG. 3 corresponds to the alloy material
mentioned in the paragraph entitled "BACKGROUND ART" and pointed
out that a further improvement is required in respect of cutting
ability and abrasion of a tool.
[0097] In FIGS. 1 and 2, the portion shown with light color (in
FIG. 1, the portion indicated as proeutectic .alpha.-Al) is a
dendrite. At the boundary zone thereof, eutectic lamella texture
(shown as dark colored portion) including eutectic Si particles
(indicated as eutectic Si in FIG. 1) and other second phase
particles is distributed in the shape of a three dimensional
network. To the contrary, FIG. 3 showing the conventional aluminum
alloy material reveals that the second phase of the dendrite
boundary zone has been divided and Si particles have been changed
to an independently distributed texture form.
[0098] The aluminum alloy material according to the present
invention is made by considering the fact that the differences of
the aforementioned metal textures influence cutting ability and
abrasion and/or damage on a cutting tool. Concretely, the aluminum
alloy material defines the dendrite arm spacing (hereinafter
referred as "DAS") and the eutectic lamella texture formed at the
dendrite boundary zone.
[0099] In the metal texture, it is required that the average DAS
(see FIG. 1) is 1-200 .mu.m. The reason for limiting the average
DAS within the aforementioned range is as follows. If the average
DAS is less than 1 .mu.m, although the cooling rate at the time of
casting should be 1,000.degree. C./sec. or more, the cooling rate
exceeds the manufacture limitation as an ingot member. To the
contrary, if the average DAS exceeds 200 .mu.m, cutting ability and
mechanical property will remarkably deteriorate. The preferable
average DAS is 3-100 .mu.m.
[0100] At the dendrite boundary zone, an eutectic lamella texture
containing the eutectic Si particles each having a mean particle
diameter of 0.01-5 .mu.m and other second phase particles is formed
in the aluminum host phase. At the time of cutting, the eutectic Si
particles, even a single Si particle, become chip breaking origins,
which improves cutting ability. Furthermore, the eutectic Si
particles form layer-like eutectic lamella texture, and the
eutectic lamella texture can be separated as if the eutectic
lamella texture is peeled off, which improves cutting ability.
Since such eutectic lamella texture is distributed in a continuous
three-dimensional network, the aforementioned separation occurs
continuously. As a result, cutting ability can be improved and
abrasion of a cutting tool can be suppressed. To the contrary, in
the metal texture form shown id FIG. 3, since Si particles as chip
breaking origins are independently distributed, the cutting ability
and abrasion of a cutting tool is inferior to those of the metal
texture distributed in the shape of a network as shown in FIGS. 1
and 2.
[0101] If the mean particle diameter of the eutectic Si particle is
less than 0.01 .mu.m, the cutting ability improvement effect is
poor. Furthermore, The eutectic Si particle tends to increase in
size as the Si content increases. If the mean particle diameter
exceeds 5 .mu.m, although good cutting ability can be obtained, a
tool will be heavily abraded or damaged such as chipped as the
grain size becomes larger. Accordingly, in order to realize both
good cutting ability and suppression of tool damage, the mean
particle diameter of eutectic Si particle is limited to 0.01-5
.mu.m. Especially, from the viewpoint of suppressing tool damage,
the preferable mean particle diameter is 0.1-3 .mu.m.
[0102] The aforementioned other second phase particles are
particles generated between Al, such as a CuAl.sub.2 and Al--Fe--Si
series, Al--Mn--Si series, Al--Cr--Si series and Al--Fe series, and
an additional element. The preferable mean particle diameter is
0.1-0.3 .mu.m.
[0103] As shown in FIG. 1, the size the eutectic lamella texture is
represented by the skeleton line length (L) in the longitudinal
direction and the width (W). The skeleton line length (L) is the
length of the skeleton line showing the frame of the eutectic
lamella texture, and the width (W) is the maximum width in the
direction perpendicular to the skeleton line. In the present
invention, the eutectic lamella texture is defined by the mean
values of the aforementioned length and width and the ratio
thereof, wherein the mean skeleton line length (Lm) is 0.5 .mu.m or
more, and the mean width (Wm) is 0.5 .mu.m or more. If the mean
skeleton line length (Lm) and mean width (Wm) are less than 0.5
.mu.m, respectively, good cutting ability cannot be obtained. The
preferable average skeleton line length (Lm) is 3 .mu.m or more,
and the preferable average width (Wm) is 1 .mu.m or more.
Furthermore, it is preferable to be a long and slender
configuration in which the mean value (L/Wm) of the ratio (L/W) of
the skeleton line length (L) to the mean width (W) is 3 or more,
because this configuration is excellent in continuous
separation.
[0104] In the aforementioned eutectic lamella texture, if the
number of particles of the eutectic Si particles and the other
second phase particles constituting the eutectic lamella texture
and the area share are specified, more excellent cutting ability
can be obtained. That is, in the eutectic lamella texture, it is
preferable that the eutectic Si particles and other second phase
particles exist 500 pieces/mm.sup.2 or more in total, and the area
share of these particles is 0.1-50%. If the total number of
particles is less than 500 pieces/mm.sup.2 or the area share is
less than 0.1%, the cutting ability improving effect becomes poor.
Furthermore, the number of eutectic Si particles and the area share
tend to become larger as the Si content increases, and even if the
area share exceeds 50%, good cutting ability can be obtained.
However, if the area share exceeds 50%, the mechanical strength of
the alloy material, especially the ductility ability (tensile
strength) and the corrosion resistance, deteriorates. Therefore,
the upper limit of the area share should be 50%. From the viewpoint
of suppressing deterioration of mechanical strength and corrosion
resistance while keeping cutting ability, the especially preferable
total number of the eutectic Si particles and other second phase
particles is 1,000 pieces/mm.sup.2 or more, and the especially
preferable area share is 0.3-40%.
[0105] The aluminum alloy material having the aforementioned metal
texture is manufactured by the methods according to claims 79-89.
That is, the alloy material having network-shaped eutectic lamella
texture can be manufactured by using an alloy having a
predetermined chemical compositions and specifying the terms and
conditions of casting.
[0106] A molten aluminum alloy having predetermined chemical
compositions and held at not less than the solidus temperature is
continuously cast at the casting rate of 30-5,000 mm/min. and the
cooling rate of 10-600.degree. C./sec. to form a shape member
having a predetermined cross-section. In the solidification
process, fine and rounded eutectic Si particles each having a
nucleus of Si--Sr compound in a molten metal are dispersed in the
aluminum, and dendrite grows up to mean DAS in the aforementioned
range. At the dendrite boundary zone, eutectic lamella texture
containing eutectic Si particles and other second phase particles
is formed in the shape of a network of a certain size.
[0107] If the casting rate is below 30 mm/min., eutectic Si
particles become rough to cause a low-density distribution of
particles, resulting in poor cutting ability and heavy damage of
cutting tool. To the contrary, if the casting rate exceeds 5,000
mm/min., a shape member having a predetermined cross-section cannot
be obtained. Furthermore, casting defects such as solidification
cracks and pores occur, which may cause poor casting surface. The
preferable casting rate is 50-3,000 mm/min., more preferably
100-2,000 mm/min.
[0108] If the cooling rate is less than 10.degree. C./sec.,
eutectic Si particles become rough to cause a low-density
distribution of particles, causing heavy damage of cutting tool. To
the contrary, in order to attain the cooling rate exceeding
600.degree. C./sec., special equipment and special process control
are required, which deteriorates productivity. Furthermore, a cost
problem will also arise. The preferable cooling rate is
30-500.degree. C./sec., more preferably 30-300.degree. C./sec.
[0109] The continuous casting method is not limited to a specific
one as long as the aforementioned casting conditions can be
attained. A vertical-type continuous casting process and a
horizontal continuous casting process can be exemplified.
Furthermore, direct cooling can be recommended in order to attain
the aforementioned cooling rate.
[0110] The cross-sectional configuration of the shape member to be
cast is not limited at all. A circular cross-section configuration,
a polygonal cross-sectional configuration and, other heteromorphic
cross-sectional configuration can be exemplified. A non-hollow
member can be recommended. Furthermore, a hollow member which
includes a hollow portion in a cross section is also included in
the present invention.
[0111] In case of a non-hollow member, it is preferable that the
member has a cross section circumscribed to a circle with a
diameter of 10-150 mm. If the diameter of the circumscribed circle
is less than 10 mm, the molten metal flow deteriorates remarkably,
which makes it difficult to form a predetermined configuration. To
the contrary, if the diameter exceeds 150 mm, the cooling becomes
insufficient due to the increased cross-section, which makes it
difficult to attain the aforementioned cooling rate. As a result,
it becomes difficult to form a network-shaped eutectic lamella
texture, which in turn may cause deterioration of cutting
ability.
[0112] The aging treatment to the continuously cast shape member is
performed by holding the member at 100-300.degree. C. for 0.5-100
hours. During this period, the element dissolved at the time of
casting is deposited in the host phase, causing maximum mechanical
strength and excellent cutting ability. If the aging temperature is
less than 100.degree. C. or the holding time is less than 0.5
hours, the aging becomes insufficient. Thus, the quality of the
finished surface at the time of cutting deteriorates, and neither
cutting ability nor mechanical strength increases. Furthermore, if
the aging temperature exceeds 300.degree. C. or the holding time
exceeds 100 hours, the aging will be excessive, resulting in
deteriorated cutting ability and decreased mechanical strength. The
preferable aging conditions are to hold the member at
120-220.degree. C. for 1-30 hours.
[0113] The surface layer of the cast shape member includes
heterogeneous layers, such as an inverse-segregation layer, a chill
layer and a rough cell layer, which are formed at the time of
solidification. Since the heterogeneous layers deteriorate the
quality of shape member, it is preferable to remove the
heterogeneous layers by eliminating the surface depth of 0.1-10 mm.
If the elimination amount of the surface layers is less than 0.1
mm, the heterogeneous layer cannot be removed sufficiently. The
elimination of 10 mm depth can exclude the heterogeneous layers
assuredly. Elimination of more than 10 mm depth has no
significance, and the materials will be wasted. The preferable
elimination amount is 0.2-5 mm in depth. The surface layer
elimination may be performed after the casting but before the
aging, or after the aging but before the secondary-forming
processing. Furthermore, the elimination method is not limited, and
peeling processing and scalping processing can be exemplified.
[0114] If necessary, the cast shape member may be subjected to
secondary forming processing to form a predetermined shape before
or after the aging. The secondary forming processing method is not
limited to a specific so long as the method is a plastic working
method by which a cross-section area decreases. Drawing, extruding
and rolling can be exemplified. It is preferable that the
processing is performed under the conditions of: the working
temperature of 400.degree. C. or less; and the cross-sectional area
reduction ratio (i.e., cross-sectional area before
processing/cross-sectional area after processing) is 30% or less.
If the working temperature exceeds 400.degree. C., the eutectic Si
particles dispersed in the eutectic lamella texture condenses to
become rough and spherical shape, which deteriorates cutting
ability. Furthermore, if the processing is performed so that the
cross-sectional area reduction ratio exceeds 30%, the eutectic
lamella texture is fractured, which deteriorates cutting ability
and alloy material quality. The preferable conditions of the
secondary forming processing are: the working temperature of
250.degree. C. or less and the cross-sectional area reduction ratio
of 20% or less.
[0115] Furthermore, the heat treatment, such as homogenization
processing and solution treatment, before the aging treatment or
before the secondary forming processing may be performed
appropriately.
[0116] The aluminum alloy material cast according to the present
invention or the member to which the secondary forming processing
was performed after the casting is cut by a saw, a shear, etc. For
example, although the member may be cut into a short member less
than 1 m in length, a long member 1-10 m in length or a blank
member, these cut members are included in this invention
irrespective of length.
[0117] Other manufacturing conditions follow a conventional
method.
[0118] Each invention has the following effects.
[0119] According to the invention as recited in claim 1, since Si
particles are fined and rounded by Sr, an aluminum alloy that is
excellent in chip breaking nature and causes less abrasion or
damage of a cutting tool can be obtained. Furthermore, since the
aluminum alloy contains Mg and Zn, the aluminum alloy is excellent
in alumite processability and plastic-working nature.
[0120] According to the invention as recited in claim 2, the
aluminum alloy more excellent in mechanical property can be
obtained.
[0121] According to the invention as recited in claim 3, an
aluminum alloy is more excellent in cutting ability can be
obtained.
[0122] According to the invention as recited in claim 4, an
aluminum alloy more excellent in mechanical property and alumite
processability can be obtained.
[0123] According to the invention as recited in claim 5, since Si
particles are further rounded and fined, an aluminum alloy which is
excellent in chip breaking nature and causes less damage or
abrasion of a cutting tool can be obtained.
[0124] According to the invention as recited in claim 6, since Si
particle can be further rounded and fined by Sr, or by Si and Na,
Ca, an aluminum alloy which is excellent in chip breaking nature
and causes less damage or abrasion of a cutting tool can be
obtained. An aluminum alloy excellent in mechanical property,
corrosion resistance, alumite processability and plastic-working
nature because of the existence of Mg and Zn can be obtained. Cu
improves mechanical property. Fe promotes dispersion of Si as an
individual particle, which improves cutting ability. Cr and Mn
enhance mechanical strength. Zr enhances mechanical strength,
corrosion resistance and cutting ability. Furthermore, Ti enhances
mechanical strength and corrosion resistance.
[0125] According to the invention as recited in claim 7, the
aluminum alloy more excellent in mechanical property can be
obtained.
[0126] According to the invention as recited in claim 8, an
aluminum alloy which is more excellent in cutting ability can be
obtained.
[0127] According to the invention as recited in claim 9, an
aluminum alloy which is more excellent in mechanical property and
alumite processability can be obtained.
[0128] According to the invention as recited in claim 10, since Si
particle are further rounded and fined, an aluminum alloy which is
excellent in chip breaking nature and causes less damage or
abrasion of a cutting tool can be obtained.
[0129] According to the invention as recited in claim 11, an
aluminum alloy more excellent in mechanical property can be
obtained.
[0130] According to the invention as recited in claim 12, since Si
are dispersed as an individual particle, more excellent
chip-breaking nature can be maintained.
[0131] According to the invention as recited in claim 13, an
aluminum alloy more excellent in mechanical property and corrosion
resistance can be obtained.
[0132] According to the invention as recited in claim 14, an
aluminum alloy more excellent in mechanical property, corrosion
resistance and cutting ability can be obtained.
[0133] According to the invention as recited in claim 15, an
aluminum alloy more excellent in mechanical property and corrosion
resistance can be obtained.
[0134] According to the invention as recited in claim 16, since Si
particle can be further rounded and fined, an aluminum alloy which
is excellent in chip breaking nature and causes less damage or
abrasion of a cutting tool can be obtained.
[0135] According to the invention as recited in claim 17, an
aluminum alloy more excellent in mechanical property can be
obtained.
[0136] According to the invention as recited in claim 18, since Si
can be dispersed as an individual particle, more excellent
chip-breaking nature can be maintained.
[0137] According to the invention as recited in claim 19 or 20, an
aluminum alloy more excellent in mechanical property and corrosion
resistance can be obtained.
[0138] According to the invention as recited in claim 21, an
aluminum alloy more excellent in mechanical property, corrosion
resistance and cutting ability can be obtained.
[0139] According to the invention as recited in claim 22, an
aluminum alloy more excellent in mechanical property and corrosion
resistance can be obtained.
[0140] According to the invention as recited in claim 23 or 24,
since Si particle can be further rounded and fined, an aluminum
alloy which is excellent in chip breaking nature and causes less
damage or abrasion of a cutting tool can be obtained.
[0141] According to the invention as recited in claim 25, since Si
particle is fined and rounded, the aluminum alloy material has good
chip breaking nature, and causes less abrasion and damage on a
cutting tool. Furthermore, it is also excellent in mechanical
property, alumite processability and plastic working nature by
other additional elements.
[0142] According to the invention as recited in claim 26, since the
aforementioned Si particle is fined, there are still less abrasion
and damage on a cutting tool.
[0143] According to the invention as recited in claim 27, since the
aforementioned Si particle is rounded, there are still less
abrasion and damage on a cutting tool.
[0144] According to the invention as recited in claim 28, since Si
particle is fined and rounded, the aluminum alloy material has good
chip breaking nature, and causes less abrasion and damage on a
cutting tool. Furthermore, it is also excellent in mechanical
property, alumite processability and plastic working nature by
other additional elements.
[0145] According to the invention as recited in claim 29, since the
aforementioned Si particle is fined, there are still less abrasion
and damage on a cutting tool.
[0146] According to the invention as recited in claim 30, since the
aforementioned Si particle is rounded, there are still less
abrasion and damage on a cutting tool.
[0147] According to the invention as recited in claim 31, it is
possible to manufacture the first aluminum alloy material which has
fined and rounded Si particles, has good chip breaking nature,
causes less abrasion and damage on a cutting tool, and is excellent
in mechanical property, alumite processability and plastic working
nature.
[0148] According to the invention as recited in claim 32, an
aluminum alloy material with the best cutting ability can be
manufactured.
[0149] According to the invention as recited in claim 33, an
aluminum alloy material with the best cutting ability, mechanical
property and corrosion resistance can be manufactured.
[0150] According to the invention as recited in claim 34, an
aluminum alloy material with the best cutting ability, mechanical
property and corrosion resistance can be manufactured. Furthermore,
productivity is also excellent.
[0151] According to the invention as recited in claim 35, an
aluminum alloy material with the best mechanical property and
corrosion resistance can be manufactured.
[0152] According to the invention as recited in claim 36, an
aluminum alloy material with the best mechanical property can be
manufactured.
[0153] According to the invention as recited in claim 37, an
aluminum alloy material which has fined surface recrystallized
structure, and is excellent especially in mechanical property can
be manufactured.
[0154] According to the invention as recited in claim 38, an
aluminum alloy material whose mechanical property is further
improved can be manufactured.
[0155] According to the invention as recited in claim 39, it is
possible to manufacture the second aluminum alloy material which
has fined and rounded Si particles, has good chip breaking nature,
causes less abrasion and damage on a cutting tool, and is excellent
in mechanical property, alumite processability and plastic working
nature.
[0156] According to the invention as recited in claim 40, an
aluminum alloy material with the best cutting ability can be
manufactured.
[0157] According to the invention as recited in claim 41, an
aluminum alloy material with the best cutting ability, mechanical
property and corrosion resistance can be manufactured.
[0158] According to the invention as recited in claim 42, an
aluminum alloy material with the best cutting ability, mechanical
property and corrosion resistance can be manufactured. Furthermore,
productivity is also excellent.
[0159] According to the invention as recited in claim 43, an
aluminum alloy material with the best mechanical property and
corrosion resistance can be manufactured.
[0160] According to the invention as recited in claim 44, an
aluminum alloy material with the best mechanical property can be
manufactured.
[0161] According to the invention as recited in claim 45, an
aluminum alloy material which has fined surface recrystallized
structure, and is excellent especially in mechanical property can
be manufactured.
[0162] According to the invention as recited in claim 46, an
aluminum alloy material whose mechanical property is further
improved can be manufactured.
[0163] According to the invention as recited in claim 47, since Si
particle is fined and rounded by Sr, and eutectic lamella texture
is formed at the dendrite boundary zone, it is possible to obtain
an aluminum alloy material comprised of this alloy which is
excellent in cutting ability and causes less abrasion and damage on
a cutting tool. Furthermore, it is possible to obtain an aluminum
alloy which is excellent in mechanical property, especially tensile
property, corrosion resistance, alumite processability and plastic
working nature because of the existence of Mg, Cu and Zn.
[0164] According to the invention as recited in claim 48, an
aluminum alloy more excellent in mechanical property can be
obtained.
[0165] According to the invention as recited in claim 49, an
aluminum alloy more excellent in cutting ability can be
obtained.
[0166] According to the invention as recited in claim 50, an
aluminum alloy more excellent in mechanical property and cutting
ability can be obtained.
[0167] According to the invention as recited in claim 51, an
aluminum alloy more excellent in mechanical property and alumite
processability can be obtained.
[0168] According to the invention as recited in claim 52, since Si
particle can be further rounded and fined, an aluminum alloy which
is excellent in chip breaking nature and causes less damage or
abrasion of a cutting tool can be obtained.
[0169] According to the invention as recited in claim 53, since Si
particle is fined and rounded by Sr, or Sr and any one of Na, Sb
and Ca, and eutectic lamella texture is formed at the dendrite
boundary zone, it is possible to obtain an aluminum alloy material
comprised of this alloy which is excellent in cutting ability and
causes less abrasion and damage on a cutting tool. Furthermore, Mg,
Zn and Cu improve mechanical property, especially tensile
characteristics, corrosion resistance, alumite processability and
plastic working nature. Furthermore, any one of Ti, B, C and Sc
causes fined ingot texture and suppresses appearance of macro
patterns and solidification cracks. Fe promotes dispersion of Si as
an individual particle, which improves cutting ability. Cr and Mn
improve mechanical strength. Zr or V fines ingot texture,
suppresses appearance of macro patterns and solidification cracks,
and further improves cutting ability by forming intermetallic
compounds. Ni forms intermetallic compounds, which improves cutting
ability. Any one of Sn, Bi and In improves cutting ability.
[0170] According to the invention as recited in claim 54, an
aluminum alloy more excellent in mechanical property can be
obtained.
[0171] According to the invention as recited in claim 55, an
aluminum alloy more excellent in cutting ability can be
obtained.
[0172] According to the invention as recited in claim 56, an
aluminum alloy more excellent in mechanical property and cutting
ability can be obtained.
[0173] According to the invention as recited in claim 57, an
aluminum alloy more excellent in mechanical property and alumite
processability can be obtained.
[0174] According to the invention as recited in claim 58, since Si
particle can be further rounded and fined, an aluminum alloy which
is excellent in chip breaking nature and causes less damage or
abrasion of a cutting tool can be obtained.
[0175] According to the invention as recited in claim 59, an
aluminum alloy in which ingot texture is fined and appearance of
macro patterns and solidification cracks are suppressed can be
obtained.
[0176] According to the invention as recited in claim 60, since Si
can be dispersed as an individual particle, more excellent
chip-breaking nature can be maintained.
[0177] According to the invention as recited in claim 61, an
aluminum alloy more excellent in mechanical property and corrosion
resistance can be obtained.
[0178] According to the invention as recited in claim 62, an
aluminum alloy in which ingot texture is fined, appearance of macro
patterns and solidification cracks are suppressed and cutting
ability is excellent, can be obtained.
[0179] According to the invention as recited in claim 63, an
aluminum alloy more excellent in cutting ability can be
obtained.
[0180] According to the invention as recited in claim 64, since Si
particle can be further rounded and fined, an aluminum alloy which
is excellent in chip breaking nature and causes less damage or
abrasion of a cutting tool can be obtained.
[0181] According to the invention as recited in claim 65, an
aluminum alloy more excellent in cutting ability can be
obtained.
[0182] According to the invention as recited in any one of claims
66-68, an aluminum alloy in which ingot texture is fined and
appearance of macro patterns and solidification cracks are
suppressed can be obtained.
[0183] According to the invention as recited in claim 69, since Si
can be dispersed as an individual particle, more excellent
chip-breaking nature can be maintained.
[0184] According to the invention as recited in claim 70 or 71, an
aluminum alloy more excellent in mechanical property and corrosion
resistance can be obtained.
[0185] According to the invention as recited in claim 72 or 73, an
aluminum alloy in which ingot texture is fined, appearance of macro
patterns and solidification cracks are suppressed and cutting
ability is excellent, can be obtained.
[0186] According to the invention as recited in claim 74, an
aluminum alloy in which ingot texture is fined and appearance of
macro patterns and solidification cracks are suppressed can be
obtained.
[0187] According to the invention as recited in claim 75, an
aluminum alloy more excellent in cutting ability can be
obtained.
[0188] According to the invention as recited in any one of claims
76-78, since Si particle can be further rounded and fined, an
aluminum alloy which is excellent in chip breaking nature and
causes less damage or abrasion of a cutting tool can be
obtained.
[0189] According to the invention as recited in any one of claims
79-81, an aluminum alloy more excellent in cutting ability can be
obtained.
[0190] According to the invention as recited in claim 82, since
eutectic Si particles can be served as chip breaking origins
independently, cutting ability is improved. Furthermore, since
eutectic lamella texture can be continuously separated, cutting
ability is improved. Furthermore, since the eutectic Si particles
are fined and rounded, abrasion and damage on a cutting tool can be
suppressed. Furthermore, this aluminum alloy is also excellent in
mechanical property, especially tensile characteristics, corrosion
resistance, alumite processability and plastic-working nature.
[0191] According to the invention as recited in claim 83, an
aluminum alloy material which is more excellent in cutting ability
and capable of suppressing abrasion and damage on a cutting tool
can be obtained.
[0192] According to the invention as recited in claim 84, an
aluminum alloy material which is further improved in cutting
ability and mechanical characteristics can be obtained.
[0193] According to the invention as recited in claim 85, abrasion
and damage on a cutting tool can be suppressed while keeping
excellent cutting ability.
[0194] According to the invention as recited in claim 86, an
aluminum alloy material which is further improved in cutting
ability can be obtained.
[0195] According to the invention as recited in claim 87, an
aluminum alloy material which is further improved in cutting
ability can be obtained.
[0196] According to the invention as recited in claim 88, cutting
ability can be further improved, and abrasion and damage on a
cutting tool can be suppressed.
[0197] According to the invention as recited in claim 89, cutting
ability can be further improved, and abrasion and damage on a
cutting tool can be suppressed.
[0198] According to the invention as recited in claim 90, since
eutectic Si particles can be served as chip breaking origins
independently, cutting ability is improved. Furthermore, since
eutectic lamella texture can be continuously separated, cutting
ability is improved. Furthermore, since the eutectic Si particles
are fined and rounded, abrasion and damage on a cutting tool can be
suppressed. Furthermore, this aluminum alloy is also excellent in
mechanical property, especially tensile characteristics, corrosion
resistance, alumite processability and plastic-working nature.
[0199] According to the invention as recited in claim 91, an
aluminum alloy material which is more excellent in cutting ability
and capable of suppressing abrasion and damage on a cutting tool
can be obtained.
[0200] According to the invention as recited in claim 92, an
aluminum alloy material which is further improved in cutting
ability and mechanical characteristics can be obtained.
[0201] According to the invention as recited in claim 93, abrasion
and damage on a cutting tool can be suppressed while keeping
excellent cutting ability.
[0202] According to the invention as recited in claim 94, an
aluminum alloy material which is further improved in cutting
ability can be obtained.
[0203] According to the invention as recited in claim 95, an
aluminum alloy material which is further improved in cutting
ability can be obtained.
[0204] According to the invention as recited in claim 96, cutting
ability can be further improved, and abrasion and damage on a
cutting tool can be suppressed.
[0205] According to the invention as recited in claim 97, cutting
ability can be further improved, and abrasion and damage on a
cutting tool can be suppressed.
[0206] According to the invention as recited in claim 98, it is
possible to manufacture the third aluminum alloy material that has
eutectic Si particles and eutectic lamella texture, causes less
abrasion and damage on a cutting tool while keeping outstanding
cutting ability, and is excellent in mechanical property,
especially tensile characteristics, corrosion resistance, alumite
processability and plastic-working nature.
[0207] According to the invention as recited in claim 99 or 100,
especially, the aforementioned eutectic Si particles and
aforementioned eutectic lamella texture can be formed
assuredly.
[0208] According to the invention as recited in claim 101, since
the elements dissolved can fully deposited at the time of casting,
an aluminum alloy material excellent especially in cutting ability
and mechanical property can be manufactured.
[0209] According to the invention as recited in claim 102, a
non-hollow member having the aforementioned eutectic Si particles
and eutectic lamella texture can be manufactured.
[0210] According to the invention as recited in claim 103,
especially the molten metal flow is good, and the aforementioned
cooling rate can be easily achieved.
[0211] According to the invention as recited in claim 104, surface
heterogeneous layers can be eliminated, and therefore a high
quality aluminum alloy material can be obtained.
[0212] According to the invention as recited in claim 105,
heterogeneous layers can be eliminated assuredly.
[0213] According to the invention as recited in claim 106,
aggregation of eutectic Si particles and/or destruction of eutectic
lamella texture can be prevented, and therefore an aluminum alloy
material can be processed into any desired configuration while
maintaining excellent cutting ability.
[0214] According to the invention as recited in claim 107 or 108,
cutting ability can be maintained assuredly even if a secondary
forming processing is performed.
[0215] According to the invention as recited in claim 109, it is
possible to manufacture the third aluminum alloy material that has
eutectic Si particles and eutectic lamella texture, causes less
abrasion and damage on a cutting tool while keeping outstanding
cutting ability, and is excellent in mechanical property,
especially tensile characteristics, corrosion resistance, alumite
processability and plastic-working nature.
[0216] According to the invention as recited in claim 110 or 111,
especially, the aforementioned eutectic Si particles and
aforementioned eutectic lamella texture can be formed
assuredly.
[0217] According to the invention as recited in claim 112, since
the elements dissolved can fully deposited at the time of casting,
an aluminum alloy material excellent especially in cutting ability
and mechanical property can be manufactured.
[0218] According to the invention as recited in claim 113, a
non-hollow member having the aforementioned eutectic Si particles
and eutectic lamella texture can be manufactured.
[0219] According to the invention as recited in claim 114,
especially the molten metal flow is good, and the aforementioned
cooling rate can be easily achieved.
[0220] According to the invention as recited in claim 115, surface
heterogeneous layers can be eliminated, and therefore a high
quality aluminum alloy material can be obtained.
[0221] According to the invention as recited in claim 116,
heterogeneous layers can be eliminated assuredly.
[0222] According to the invention as recited in claim 117,
aggregation of eutectic Si particles and/or destruction of eutectic
lamella texture can be prevented, and therefore an aluminum alloy
material can be processed into any desired configuration while
maintaining excellent cutting ability.
[0223] According to the invention as recited in claims 118 and 119,
cutting ability can be maintained assuredly even if a secondary
forming processing is performed.
BRIEF DESCRIPTION OF DRAWINGS
[0224] FIG. 1 is a photograph showing metal texture of an aluminum
alloy material corresponding to claims 71-75 of the present
invention.
[0225] FIG. 2 is a photograph showing other metal texture of other
aluminum alloy material corresponding to claims 71-75 of the
present invention.
[0226] FIG. 3 is a photograph showing metal texture of a
conventional aluminum alloy material.
[0227] FIG. 4 is a photograph showing a cut surface of 98.2% peel
rate to evaluate the quality of the machined surface of Example
IIA.
[0228] FIG. 5 is a photograph showing the cut surface 3.4% peel
rate to evaluate the quality of the machined surface of Example
IIA.
[0229] FIG. 6 is a cross-sectional view of a principal part of a
gas pressurization type hot top casting apparatus used in Examples
IIA, IIB and IIC.
[0230] FIG. 7 is a cross-sectional view of a principal part of a
horizontal continuous casting apparatus used in Example IIB.
EXAMPLES
I. First and Second Aluminum Alloys, Aluminum Alloy Materials and
Manufacturing Methods Thereof (Examples Corresponding to claims
1-46)
[0231] Aluminum alloys of compositions of Al No. I-1-I-17 shown in
Table 1 were prepared. The alloy No. I-1 and I-2 includes Mg, Si,
Zn and Sr, and the balance being aluminum and impurities, and the
compositions correspond to claims 1-5 of the present invention. The
alloys Nos. I-3 to I-12 include eight optional selective elements
in the aforementioned elements, and the compositions correspond to
claims 6-24. The alloys Nos. I-13 to I-17 are comparative
compositions.
[0232] From these aluminum alloy materials, round bars were made by
billet casting, extrusion, and drawing.
[0233] First, a billet was made at the casting rate of 80 mm/min.
by DC casting. The billet was homogenized by holding at 520.degree.
C. for 10 hours, and then extruded into a round bar with a diameter
of 15 mm at the billet temperature of 450.degree. C., the extrusion
product rate of 12 m/min., and the extrusion ratio of 35. This
extruded member is held at 540.degree. C. for 3 hours for a
solution treatment, then drawn at the reduction rate of 25%, and
aged by holding at 160.degree. C. for 5 hours to thereby obtain a
test piece.
[0234] On each prepared test piece (drawn member), the proof
strength of 0.2%, the tensile strength and the fracture elongation
were measured. Further, the chip breaking nature, the corrosion
resistance, the abrasion of a tool, the alumite processability and
the plastic-working nature were evaluated by the following
method.
[0235] [Chip Breaking Nature, Tool Abrasion]
[0236] Each test piece was wet cut using a superhard chip at the
cutting rate of 150 m/min., the feeding rate of 0.2 mm/rev. to form
a slit of 1.0 mm depth. The chip breaking nature was evaluated by
chip number/100 g.
[0237] [Corrosion Resistance]
[0238] A salt spray test based on JIS Z2371 was performed, and the
corrosion resistance was measured by the corrosion weight loss due
to 1,000 hours spray.
[0239] [Tool Abrasion]
[0240] Continuous cutting for 5 minutes is performed under the
conditions of cutting rate of 200 m/min., feeding rate of 0.2
mm/rev., and slitting of 10 mm by dry type cutting using a
high-speed slab cutting-edge byte, and the abrasion width of the
byte's flank was measured.
[0241] [Alumite Processability]
[0242] Sulfuric acid alumite processing was conducted by a
conventional method, and evaluation was performed by the thickness
of the generated alumite coat.
[0243] [Plastic-Working Nature]
[0244] This was evaluated by the rate of the limit lump rate
obtained by a lump nature examination. In this examination, The
crack generating limitation by cold working (forging) was
investigated and evaluated by this result.
[0245] These results are collectively shown in Table 1. Regarding
the chip breaking nature, the corrosion resistance, the abrasion of
a tool, the alumite processability and the plastic-working nature,
they were evaluated relatively on the basis of comparison alloy No.
I-13. ".largecircle." denotes a performance equivalent to the
comparison alloy No.I-13, ".circleincircle." denotes a performance
superior to the comparison alloy, ".DELTA." denotes a performance
inferior to the comparison alloy, and "X" denotes a performance
further inferior to the comparison alloy.
1TABLE 1 Alloy Chemical compositions of Al--Mg--Si series alloy No.
(mass %, balance being Al and impurities) (I-n) Mg Si Zn Sr Cu Fe
Mn Cr Zr Ti Na Ca Other Invention 1 1.0 1.8 0.3 0.03 -- -- -- -- --
-- -- -- -- 2 0.6 4.8 0.2 0.05 -- -- -- -- -- -- -- -- -- 3 1.0 1.8
0.3 0.03 0.2 0.2 0.01 -- -- -- -- -- 4 1.0 2.8 0.3 0.03 0.2 0.2
0.01 -- -- -- -- -- -- 5 1.0 4.8 0.3 0.03 0.2 0.2 0.01 -- -- -- --
-- -- 6 1.0 2.8 0.3 0.01 0.2 0.2 0.01 -- -- -- -- -- -- 7 1.0 2.8
0.3 0.03 0.2 0.2 0.01 -- -- -- -- -- -- 8 1.0 2.8 0.3 0.03 0.2 0.2
0.01 0.2 -- -- -- -- -- 9 1.0 2.8 0.3 0.03 0.2 0.2 0.01 -- 0.2 --
-- -- -- 10 1.0 2.8 0.3 0.03 0.2 0.2 0.01 -- -- 0.02 -- -- -- 11
1.0 2.8 0.3 0.03 0.2 0.2 0.01 -- -- -- 0.005 -- -- 12 1.0 2.8 0.3
0.03 0.2 0.2 0.01 -- -- -- -- 0.005 -- Comparative 13 1.0 0.8 -- --
0.2 0.2 0.10 -- -- -- -- -- Pb: 0.5 Bi: 0.5 14 1.0 2.8 0.3 -- 0.2
0.2 0.01 -- -- -- -- -- -- 15 1.0 4.8 0.3 -- 0.2 0.2 0.01 -- -- --
-- -- -- 16 1.0 11.5 0.3 0.03 0.2 0.2 0.01 -- -- -- -- -- -- 17 1.0
11.5 0.3 -- 0.2 0.2 0.01 -- -- -- -- -- -- Characteristics Tensile
characteristics 0.2% Alloy proof Tensile Fracture Cutting Alumite
Plastic- No. strength strength elongation division Corrosion Tool
process- working (I-n) N/mm.sup.2 N/mm.sup.2 % nature resistance
Abrasion ability nature Invention 1 290 315 15.5 .largecircle.
.largecircle. .circleincircle. .circleincircle. .largecircle. 2 315
338 9.0 .largecircle. .largecircle. .circleincircle.
.circleincircle. .largecircle. 3 305 335 14.0 .largecircle.
.largecircle. .circleincircle. .circleincircle. .largecircle. 4 312
340 12.0 .largecircle. .largecircle. .largecircle. .circleincircle.
.largecircle. 5 328 348 11.0 .circleincircle. .largecircle.
.largecircle. .largecircle. .largecircle. 6 310 339 12.5
.largecircle. .largecircle. .largecircle. .circleincircle.
.largecircle. 7 315 336 12.6 .largecircle. .largecircle.
.largecircle. .circleincircle. .largecircle. 8 320 345 13.5
.largecircle. .largecircle. .largecircle. .circleincircle.
.largecircle. 9 315 340 13.5 .largecircle. .largecircle.
.largecircle. .circleincircle. .largecircle. 10 318 340 12.5
.largecircle. .largecircle. .largecircle. .circleincircle.
.largecircle. 11 310 340 13.0 .largecircle. .largecircle.
.circleincircle. .circleincircle. .largecircle. 12 305 335 13.5
.largecircle. .largecircle. .circleincircle. .circleincircle.
.largecircle. Comparative 13 280 310 16.0 .largecircle.
.largecircle. .largecircle. .largecircle. .largecircle. 14 322 342
12.1 .largecircle. .largecircle. .DELTA. .largecircle.
.largecircle. 15 327 339 11.6 .largecircle. .largecircle. .DELTA.
.largecircle. .DELTA. 16 295 315 9.5 .circleincircle. .DELTA. X
.DELTA. X 17 290 309 7.9 .circleincircle. .DELTA. X .DELTA. X In
this Table, the underlined numeral is out of the scope of the
invention.
[0246] Furthermore, on the invention alloys No.I-i, I-3 to I-5,
I-11, I-12 and comparison alloys No.I-14 to I-17, the mean particle
diameter of Si particle, the particle diameter range, the mean
aspect ratio thereof were examined. The results are shown in Table
2 which also shows the Si content, Sr content, Na content, Ca
content, chip-breaking nature and abrasion of a tool which affect
the above.
2 TABLE 2 Si particle Mean Range of Other Character Alloy Si, Sr,
Na, Ca content particle Particle Mean Cutting No. (mass %) diameter
diameter aspect division Tool (I-n) Si Sr Na Ca (.mu.m) (.mu.m)
ratio nature Abrasion Invention 1 1.8 0.03 -- -- 1.2 0.3-3.3 1.5
.largecircle. .circleincircle. 3 1.8 0.03 -- -- 1.2 0.3-3.2 1.3
.largecircle. .circleincircle. 4 2.8 0.03 -- -- 3.1 0.8-4.2 2.3
.largecircle. .largecircle. 5 4.8 0.03 -- -- 4.9 1.2-6.6 2.8
.circleincircle. .largecircle. 11 2.8 0.03 0.005 -- 3.0 0.7-4.2 2.3
.largecircle. .circleincircle. 12 2.8 0.03 -- 0.005 3.1 0.7-4.1 2.1
.largecircle. .circleincircle. Comparative 14 2.8 -- -- -- 3.3
0.1-5.5 4.1 .largecircle. .DELTA. 15 4.8 -- -- -- 4.2 0.1-6.9 4.2
.largecircle. .DELTA. 16 11.5 0.03 -- -- 6.5 0.5-12.1 3.6
.circleincircle. X 17 11.5 -- -- -- 6.8 0.3-11.2 4.9
.circleincircle. X
[0247] From the results shown in Tables Nos. 1 and 2, it was
confirmed that the aluminum alloy materials of the invention alloy
Nos. I-1 to I-12 are excellent in chip breaking nature and abrasion
of a tool since the particles are fined and rounded irrespective of
Si addition.
[0248] II. Third and Fourth Aluminum Alloys, Alloy Materials and
Manufacturing Methods Thereof
Examples Corresponding to Claims 47-119
[0249] A. Compositions of Aluminum Alloy
[0250] Aluminum alloys having compositions of alloy No. IIA-1 to
IIA-129 shown in Table 3-8 were prepared. Each of the alloy Nos.
IIA-1 to IIA-30 includes Mg, Si, Cu, Zn, Sr and the balance being
aluminum and impurities. The compositions correspond to claims
47-52 of the invention. Alloys No. IIA-1 to IIA-10 are comparative
compositions. Alloy No. IIA-41 to IIA-108 (except for IIA-93, 94
and 97) has the basic compositions of Alloy No. IIA-30, and Alloys
No. IIA-109 to IIA-129 have the basic compositions of Alloy No.
IIA-109 to IIA-129. Both the alloys Furthermore, sixteen optional
selective elements are added to the above alloys. Alloy No. IIA-94
has basic compositions of Alloy No. IIA-7 (Mg: 1 mass %, Si: 0.8
mass %, Cu: 0.2 mass %, Zn: 0.2 mass %, Sr: 0.03 mass %), Alloy No.
IIA-93 and 97 have basic compositions of Alloy (Mg: 1 mass %, Si:
1.5 mass %, Cu: 0.2 mass %, Zn: 0.2 mass %, Sr: 0.03 mass %).
Optional additional elements are added to the above alloys. Alloy
No. IIA-41 to IIA-129 are compositions corresponding to claims
53-81.
[0251] Using these aluminum alloys as the casting materials, a
non-hollow member of a round cross-section with a diameter of 53 mm
was cast vertically and continuously by the below-mentioned gas
pressurization type hot top casting method.
[0252] [Gas Pressurization Type Hot Top Casting]
[0253] In the gas pressurization type hot top casting apparatus
shown in FIG. 6, the reference numeral "1" denotes a mold for
forming the external periphery of an ingot, and "2" denotes a
cylindrical molten metal receiving tub disposed at the upper
portion of the mold 1.
[0254] The mold 1 has an annular cavernous portion 3 for
circulating a cooling medium such as water therein. This cavernous
portion 3 is provided with a plurality of port mouths 4 opening
toward the outside. The cooling medium C introduced into the
cavernous portion 3 through an introductory tubing which is not
illustrated performs a primary cooling of the cast member S by
cooling the mold 1, and is spouted from the port mouths 4 to
perform a secondary cooling of the casting S. Furthermore, the
inner upper surface 1a of the mold 1 is lower than the exterior
upper surface 1b, to thereby form a gap 6 opened to a gas passage 5
between the inner upper surface 1a and the lower surface of the
molten metal tub 2.
[0255] The lower inner part of the molten metal tub 2 is protruded
horizontally toward the inner side of the mold 1 to form an over
hang portion 7. Accordingly, the pressurized gas F introduced into
the gas passage 5 through the gas introduction passage 8 from the
exterior is introduced under the overhang portion 7 from the gap 6.
This excludes the molten metal from the region immediately under
the over hang portion 7 to thereby make the molten metal contact to
the inner peripheral surface of the mold 1 at the position far
below the upper end of the mold 1. The contact distance between the
molten metal and the mold 1 is controlled by the flow rate of the
pressurized gas F, which in turn controls the primary cooling time
and the solidification process to obtain a cast member S. excellent
in metal texture. In the figure, "M" shows the overhang amount of
the overhang portion 7.
[0256] Furthermore, lubricating oil is introduced into a supply
passage 9 from the exterior through a passage which is not
illustrated, and supplied to the inner peripheral surface of the
mold 1 through numeral fine feed mouths 10 branched from the supply
passage 9. "11" denotes a heat-resistant packing member fitted in
the slot cut in the upper surface of the mold 1 to prevent the leak
of the gas passing through the gap 6.
[0257] According to the vertical-type continuous casting apparatus,
the casting rate and cooling rate of the present invention can be
attained, and a cast member with outstanding characteristics, such
as cutting ability, can be manufactured.
[0258] The casting conditions were the casting conditions b shown
in the following Table 9, and all of the alloys were continuously
cast successfully.
[0259] Subsequently, the surface portion of the cast non-hollow
member of 1.5 mm depth was eliminated. Thereafter, aging was
performed by holding the member at 170.degree. C. for 11 hours, to
thereby obtain a test piece.
[0260] About each test piece, the mechanical properties, such as
0.2% proof strength, tensile strength, fracture elongation (tensile
characteristics), were measured, and the homogeneity of metal
texture, plastic-working nature, cutting ability, abrasion of a
tool, quality of the machined surface, corrosion resistance,
alumite processability were examined by the following method. Then,
except for the mechanical properties, they were evaluated
relatively by comparing with various characteristics of the
extruded member consist of JIS A6262 alloy in the five following
grades.
[0261] .circleincircle..circleincircle.: Extremely excellent
[0262] .circleincircle.: Excellent
[0263] .largecircle.: Equivalent
[0264] .DELTA.: Slightly poor
[0265] X: Very poor
[0266] [Homogeneity of Metal Texture]
[0267] It is evaluated by size of dendrite texture, measured result
on space, size of eutectic lamella texture, form, continuity and
homogeneity in a test piece cross-section.
[0268] [Plastic-Working Nature]
[0269] It is evaluated by drawing at the cross-sectional area
reduction ratio of 20% and using the change rate of characteristics
from the results of the cutting ability examination and the tensil
test.
[0270] [Cutting Ability]
[0271] Wet cutting was performed by using a superhard chip at the
cutting rate of 150 m/min., feeding rate of 0.2 mm/rev. to form a
slit of 1.0 mm depth, and the chip breaking nature is examined from
chips number/100 g. Then, the cutting ability is evaluated by the
chip breaking nature.
[0272] [Abrasion of a Tool]
[0273] Continuous cutting for 5 minutes is performed under the
conditions of cutting rate of 200 m/min., feeding rate of 0. 2
mm/rev., and slitting of 10 mm by dry type cutting using a
high-speed slab cutting-edge byte, and the abrasion width of the
byte's flank was measured.
[0274] [Quality of Finished Surface]
[0275] It was evaluated by the rate (%) of the peeled portion
existing in a unit area (1 mm.sup.2) on the cut surface of the test
piece cut by the aforementioned cutting test. As examples of cut
surfaces, FIG. 3 shows the cut surface of 98.2% peeled rate, and
FIG. 4 shows the cut surface of 3.4% peeled rate.
[0276] [Cutting Crack Nature]
[0277] Wet cutting was performed by using a superhard chip at the
cutting rate of 150 m/min., feeding rate of 0.2 mm/rev. to form a
slit of 3.0 mm depth, and the chip breaking nature is examined from
chips number/100 g. Then, the Cutting crack nature was evaluated by
the incidence rate (%)of the cutting cracks within a unit area (1
mm.sup.2).
[0278] [Corrosion Resistance]
[0279] A salt spray test based on JIS Z2371 was performed, and the
corrosion resistance was measured by the corrosion weight loss due
to 1,000 hours spray.
[0280] [Alumite Processability]
[0281] Sulfuric acid alumite processing was conducted by a
conventional method, and evaluation was performed by the thickness
of the generated alumite coat.
[0282] These results are shown in Tables 3-8.
3 TABLE 3 Various Characteristics Mechanical property Frac-
Compositions of Al 0.2% ture Quality Cor- Alloy alloy (mass %,
balance being proof Tensile Elon- Texture Plastic- Tool of Cutting
rosion Alumite No. Al and impurities) strength strength gation
homo- working Cutting Abra- finished crack resis- process- (IIA-n)
Mg Si Cu Zn Sr N/mm.sup.2 N/mm.sup.2 % geneity nature alibity sion
surface nature tance ability Invention 1 0.3 2.8 0.2 0.2 0.03 285
320 7.2 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. 2 2.0 2.8 0.2 0.2 0.03 305 330 8.6 .largecircle.
.largecircle. .circleincircle. .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. 3 4.0 2.8 0.2
0.2 0.03 307 330 8.0 .largecircle. .largecircle. .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. 4 5.0 2.8 0.2 0.2 0.03 300 325 8.0 .largecircle.
.largecircle. .largecircle. .largecircle. .circleincircle.
.circleincircle. .largecircle. .largecircle. 5 6.0 2.8 0.2 0.2 0.03
290 320 7.8 .largecircle. .largecircle. .largecircle. .largecircle.
.circleincircle. .circleincircle. .largecircle. .largecircle. 6 1.0
0.3 0.2 0.2 0.03 280 315 14.5 .circleincircle. .largecircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. 7 1.0 0.8 0.2 0.2 0.03 305 330
13.0 .circleincircle. .largecircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
8 1.0 4.0 0.2 0.2 0.03 326 340 12.1 .circleincircle. .largecircle.
.circleincircle. .largecircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. 9 1.0 6.0 0.2 0.2 0.03 320 330
9.6 .largecircle. .largecircle. .circleincircle. .largecircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle. 10
1.0 8.0 0.2 0.2 0.03 305 325 9.0 .largecircle. .largecircle.
.circleincircle. .largecircle. .largecircle. .circleincircle.
.largecircle. .largecircle. 11 1.0 10.0 0.2 0.2 0.03 290 310 8.0
.largecircle. .largecircle. .circleincircle. .largecircle.
.largecircle. .circleincircle. .largecircle. .largecircle. 12 1.0
12.0 0.2 0.2 0.03 290 315 8.1 .largecircle. .largecircle.
.circleincircle. .largecircle. .largecircle. .circleincircle.
.largecircle. .largecircle. 14 1.0 2.8 0.05 0.2 0.03 280 310 12.6
.circleincircle. .largecircle. .largecircle. .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle. 15
1.0 2.8 0.1 0.2 0.03 280 320 13.0 .circleincircle. .largecircle.
.largecircle. .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. 16 1.0 2.8 0.3 0.2 0.03 308 340
13.9 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. 17 1.0 2.8 0.5 0.2 0.03 340 376 14.2
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
18 1.0 2.8 0.8 0.2 0.03 350 395 13.0 .circleincircle. .largecircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.largecircle. .circleincircle. 19 1.0 2.8 0.2 0.01 0.03 305 330
14.5 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 20 1.0 2.8 0.2 0.05 0.03 308 325 15.0
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle.
.largecircle.
[0283]
4 TABLE 4 Various Characteristics Mechanical property Frac-
Compositions of Al 0.2% ture Quality Cor- Alloy alloy (mass %,
balance being proof Tensile Elon- Texture Plastic- Tool of Cutting
rosion Alumite No. Al and impurities) strength strength gation
homo- working Cutting Abra- finished crack resis- process- (IIA-n)
Mg Si Cu Zn Sr N/mm.sup.2 N/mm.sup.2 % geneity nature alibity sion
surface nature tance ability Invention 21 1.0 2.8 0.2 0.1 0.03 315
335 14.3 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 22 1.0 2.8 0.2 0.5 0.03 332 356 11.2 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. .largecircle. 23 1.0 2.8 0.2 1.0
0.03 335 350 12.6 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
.largecircle. 24 1.0 2.8 0.2 1.5 0.03 340 355 10.9 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .largecircle.
.circleincircle. .largecircle. .largecircle. 25 1.0 2.8 0.2 0.2
0.005 306 319 12.6 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 26 1.0 2.8 0.2 0.2 0.01 310 332 15.6 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 27 1.0 2.8 0.2 0.2
0.05 308 327 16.2 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
.largecircle. 28 1.0 2.8 0.2 0.2 0.1 301 320 15.8 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. .largecircle. 29 1.0 2.8 0.2 0.2 0.2
301 322 15.1 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
.largecircle. 30 1.0 2.8 0.2 0.2 0.03 303 326 14.6 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. Comparative 31
0.01 2.8 0.2 0.2 0.03 265 305 8.2 .circleincircle. .largecircle.
.circleincircle. .largecircle. X .DELTA. .largecircle.
.largecircle. 32 7.0 2.8 0.2 0.2 0.03 280 300 7.5 .largecircle.
.largecircle. .DELTA. .largecircle. X .DELTA. .largecircle. .DELTA.
33 1.0 0.1 0.2 0.2 0.03 272 298 17.6 .circleincircle. .largecircle.
.DELTA. .circleincircle. .largecircle. .circleincircle.
.largecircle. .largecircle. 34 1.0 14.0 0.2 0.2 0.03 335 358 4.1
.DELTA. .largecircle. .circleincircle. .DELTA. .DELTA.
.largecircle. .DELTA. .DELTA. 35 1.0 2.8 -- 0.2 0.03 285 310 10.6
.circleincircle. .largecircle. .DELTA. .circleincircle.
.largecircle. .largecircle. .circleincircle. .circleincircle. 36
1.0 2.8 1.2 0.2 0.03 358 396 12.6 .largecircle. .largecircle.
.largecircle. .largecircle. .largecircle. .largecircle. .DELTA.
.largecircle. 37 1.0 2.8 0.2 -- 0.03 290 316 13.1 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .DELTA. 38 1.0 2.8 0.2 4.0 0.03
390 421 10.6 .largecircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .DELTA.
.largecircle. 39 1.0 2.8 0.2 0.2 -- 270 295 8.2 .DELTA.
.largecircle. .circleincircle. .DELTA. .largecircle. .largecircle.
.largecircle. .largecircle. 40 1.0 2.8 0.2 0.2 0.8 305 321 14.6
.largecircle. .largecircle. .circleincircle. .largecircle. .DELTA.
.largecircle. .DELTA. .largecircle. In this Table, the underlined
numeral is out of the scope of the invention.
[0284] In this table, the underlined numeral is out of the scope of
the invention.
5 TABLE 5 Various Characteristics Mechanical Al alloy compositions
property (mass %) Frac- Basic compositions Mg:1.0, 0.2% ture
Quality Cor- Alloy Si:2.8, Cu:0.2, Zn:0.2, proof Tensile Elon-
Texture Plastic- Tool of Cutting rosion Alumite No. Sr:0.03,
balance:Al and strength strength gation homo- working Cutting Abra-
finished crack resis- process- (IIA-n) impurities N/mm.sup.2
N/mm.sup.2 % geneity nature alibity sion surface nature tance
ability Invention 41 Ti: 0.003 298 319 12.8 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 42 Ti: 0.02 302 320
14.6 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 43 Ti: 0.3 308 325 13.1 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 44 B: 0.0005 302
330 15.1 .circleincircle. .circleincircle. .circleincircle.
.largecircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. 45 B: 0.005 305 320 15.2 .circleincircle.
.circleincircle. .circleincircle. .largecircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. 46 B: 0.01 308
329 14.6 .circleincircle. .largecircle. .circleincircle.
.largecircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. 47 C: 0.01 305 320 15.1 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 48 C: 0.15 295 315
14.0 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 49 Fe: 0.05 285 318 16.2 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. 50 Fe: 0.2 296
325 15.1 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. 51 Fe: 0.7 291 323 13.6 .largecircle.
.largecircle. .circleincircle. .largecircle. .largecircle.
.circleincircle. .largecircle. .largecircle. 52 Cr: 0.03 305 318
14.1 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. 53 Cr: 0.2 302 325 16.2 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. 54 Cr: 0.7 308
330 15.1 .largecircle. .largecircle. .circleincircle. .largecircle.
.circleincircle. .circleincircle. .largecircle. .largecircle. 55
Mn: 0.1 309 328 14.6 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. 56 Mn: 0.3 319 338 12.5
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
57 Zr: 0.1 310 329 13.6 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. 58 Zr: 0.3 312 329 12.9
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
59 Zr: 0.7 309 336 14.9 .largecircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. .largecircle. 60 V: 0.1 296 318 10.2 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. 61 V: 0.3 296
322 11.2 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle.
[0285]
6 TABLE 6 Various Characteristics Mechanical Al alloy compositions
property (mass %) Frac- Basic compositions Mg:1.0, 0.2% ture
Quality Cor- Alloy Si:2.8, Cu:0.2, Zn:0.2, proof Tensile Elon-
Texture Plastic- Tool of Cutting rosion Alumite No. Sr:0.03,
balance:Al and strength strength gation homo- working Cutting Abra-
finished crack resis- process- (IIA-n) impurities N/mm.sup.2
N/mm.sup.2 % geneity nature alibity sion surface nature tance
ability Invention 62 Sc: 0.07 300 325 14.6 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 63 Sc: 0.16 310 330
13.1 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 64 Ni: 0.003 302 320 15.2 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 65 Ni: 0.2 315 340
11.6 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 66 Ni: 0.7 318 342 10.9 .largecircle. .largecircle.
.circleincircle. .circleincircle. .largecircle. .circleincircle.
.largecircle. .largecircle. 67 Na: 0.01 300 320 13.6
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle. 68
Na: 0.1 302 328 13.1 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. 69 Sb: 0.01 305 325 13.0
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle. 70
Sb: 0.1 304 326 12.9 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. 71 Ca: 0.01 301 322 14.6
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle. 72
Ca: 0.1 298 320 12.6 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. 73 Ca: 0.3 300 325 12.4
.largecircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. .largecircle. 74
Sn: 0.05 315 335 13.2 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. 75 Sn: 0.2 308 330 14.2
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. .largecircle. 76
Sn: 0.4 310 328 13.9 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. .largecircle. 77 Bi: 0.05 305 332 14.1
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
78 Bi: 0.2 300 326 14.8 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. 79 Bi: 0.4 305 328 12.9
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. .largecircle. 80
In: 0.01 300 320 16.2 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. 81 In: 0.1 302 330 12.6
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. .largecircle. 82
In: 0.3 305 328 14.1 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. .largecircle.
[0286]
7 TABLE 7 Various Characteristics Mechanical Al alloy compositions
property (mass %) Frac- Basic compositions Mg:1.0, 0.2% ture
Quality Cor- Alloy Si:2.8, Cu:0.2, Zn:0.2, proof Tensile Elon-
Texture Plastic- Tool of Cutting rosion Alumite No. Sr:0.03,
balance:Al and strength strength gation homo- working Cutting Abra-
finished crack resis- process- (IIA-n) impurities N/mm.sup.2
N/mm.sup.2 % geneity nature alibity sion surface nature tance
ability Invention 88 Ti: 0.1, Fe: 0.1 306 321 12.6 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 89 Ti: 0.1, Mn: 0.1
302 320 12.8 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 90 Ti: 0.1, Cr: 0.1 310 321 10.9 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 91 Cr: 0.1, Ni: 0.1
308 320 11.6 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. 92 Sn: 0.3, Bi: 0.1 309 330 14.6 .circleincircle.
.largecircle. .circleincircle..circleincircle.
.circleincircle..circleincircle. .largecircle. .circleincircle.
.circleincircle. .largecircle. 93 Si: 1.5, Sn: 0.4, In: 0.02 ** 298
323 12.9 .circleincircle. .largecircle.
.circleincircle..circleincirc- le. .circleincircle..circleincircle.
.largecircle. .circleincircle. .largecircle. .largecircle. 94 Si:
0.8, Sn: 0.5, Bi: 0.5 * 289 319 11.6 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .largecircle. .largecircle.
.largecircle. .largecircle. 95 Ti: 0.1, Sn: 0.1 292 320 12.1
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle. 96
Fe: 0.2, Cr: 0.1 299 323 14.6 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. 97 Si: 1.5, Sn: 0.3, In: 0.05 ** 316
331 12.6 .circleincircle. .largecircle.
.circleincircle..circleincircle. .circleincircle..circleincircle.
.circleincircle. .circleincircle. .largecircle. .circleincircle. 98
Fe: 0.2, Ca: 0.1 301 320 13.9 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. 99 Ti: 0.1, Fe: 0.2, Cr: 0.1 302 326
14.1 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 100 Fe: 0.2, Zr: 0.1, Ni: 0.1 300 315 10.6
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
101 Fe: 0.2, Zr: 0.1, Bi: 0.1 305 319 10.8 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. .largecircle. 102 Ti: 0.1, Fe: 0.2,
Cr: 0.1, 295 322 14.6 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. Sb: 0.05 103 Ti: 0.1, Fe: 0.2, Mn:
0.1, Cr: 0.1 290 320 15.1 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. 104 Ti: 0.1, Fe: 0.2, V: 0.1, Ca:
0.1, 295 319 14.0 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
.largecircle. Sn: 0.1 105 C: 0.1, Fe: 0.2, Mn: 0.1, 290 315 12.6
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
Zr: 0.1, Na: 0.1 106 B: 0.1, Fe: 0.2, Mn: 0.1, Zr: 0.1, 286 310
12.1 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
.largecircle. In: 0.1 107 B: 0.1, Fe: 0.2, Mn: 0.1, Ni: 0.1, 292
318 14.6 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
.largecircle. In: 0.1 108 Fe: 0.2, B, Mn, Zr, Ni, Sb, 290 320 12.6
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. .largecircle. In:
0.1 respectively Note: * denotes: Si: 0.8 mass %, ** denotes: Si:
1.5 mass %, Mg, Cu, Zn, Sr: same mass %
[0287]
8 TABLE 8 Various Characteristics Mechanical Al alloy compositions
property (mass %) Frac- Basic compositions Mg:1.0, 0.2% ture
Quality Cor- Alloy Si:8.0, Cu:0.2, Zn:0.2, proof Tensile Elon-
Texture Plastic- Tool of Cutting rosion Alumite No. Sr:0.03,
balance:Al and strength strength gation homo- working Cutting Abra-
finished crack resis- process- (IIA-n) impurities N/mm.sup.2
N/mm.sup.2 % geneity nature alibity sion surface nature tance
ability Invention 109 Ti: 0.02 302 319 11.6 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 110 B: 0.005 302
318 10.9 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. 111 C: 0.1 298 319 12.1 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 112 Fe: 0.2 302 321
12.0 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. 113 Cr: 0.2 303 319 10.1 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. 114 Mn: 0.1 302
322 14.6 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. 115 Zr: 0.3 305 320 13.6 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. 116 V: 0.1 302
319 12.0 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. 117 Sc: 0.07 305 322 11.8 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 118 Ni: 0.2 300 318
10.1 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 119 Na: 0.1 305 321 13.9 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 120 Sb: 0.1 300 322
14.1 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 121 Ca: 0.1 300 320 13.6 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 122 Sn: 0.2 308 329
13.2 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 123 Bi: 0.2 307 320 14.9 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. .largecircle. 124 In: 0.1 302 318
12.6 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
.largecircle. 125 Ti: 0.1, Fe: 0.2 298 319 10.6 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 126 Ti: 0.1, Ni:
0.1 297 316 10.1 .circleincircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.largecircle. 127 Ti: 0.03, Fe: 0.2, Cr: 0.1 289 316 11.1
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. .largecircle. 128
B: 0.1, Fe: 0.2, Mn: 0.1, Ni: 0.1, 280 314 11.0 .circleincircle.
.largecircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. .largecircle. In: 0.1 129 Fe: 0.2,
B, Mn, Zr, Ni, Sb, 282 316 10.9 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .largecircle. Sc: 0.1 respectively
[0288]
9 TABLE 9 Casting condition a Casting condition b Molten metal
730.degree. C. 730.degree. C. temperature Amount of cooling 40
little/min. 40 little/min. water Casting diameter Diameter 120 mm
Diameter 53 mm Casting rate 150 mm/min. 300 mm/min. Lubricating oil
Castor oil Castor oil Amount of Lubricating 1 cc/min. 1 cc/min. oil
Gas Air Air Gas flow rate 0.5 litter/min. 0.5 litter/min. Protruded
amount of 10 mm 10 mm overhang portion (M)
[0289] From the results of Tables 3-8, it was confirmed that the
aluminum alloy of compositions according to the present invention
has outstanding homogeneity of metal texture, plastic-working
nature, cutting ability (including quality of finished surface and
cutting crack nature), corrosion resistance and alumite
processability, and that abrasion of a tool can also be suppressed
at the time of cutting.
[0290] B. Metal Texture and Manufacture Conditions
[0291] The manufacturing test of aluminum alloy materials were
performed using IIA-30 (Table 4) and IIA-127 (Table 8) among the
alloys of the above-mentioned compositions.
[0292] As for the casting No. IIB-1, IIB-2, IIB-5 and IIB-6, it was
cast by the vertical-type continuous casting method. As for the
casting No. IIB-3, IIB-4, IIB-7 and IIB-8, it was cast by the
horizontal continuous casting method. Each cast member was formed
into a non-hollow member (round bar) having a round cross-section.
The detail of the casting method and casting conditions are as
follows. Furthermore, as comparative examples, casting No. IIB-9,
IIB-10 were cast by a metal mold.
[0293] [Vertical-Type Continuous Casting]
[0294] Two types of non-hollow members having of round
cross-section were made under the casting conditions a and b shown
in Table 9 by the same gas pressurizing type hot top casting method
as employed in the aforementioned example of "A. Aluminum alloy
chamical compositions."
[0295] [Horizontal Continuous Casting]
[0296] In the horizontal continuous casting apparatus shown in FIG.
7, the reference numeral "20" denotes a mold, "21" denotes a
tundish, "22" denotes a fire resistance conductor for introducing
molten metal into the mold 20 from the tundish 21. Furthermore,
"23" and "24" denote fire resistance plates for specifying the
opening diameter of the molten metal inlet 32 from the conductor 22
to the mold 20.
[0297] The mold 20 has an annular cavernous portion 25 in which
cooling medium C such as water circulates, and is provided with a
plurality of port mouths 26 opened from the cavernous portion 25
toward the outside. The mold 20 has the annular cavernous portion
25 which circulates cooling mediums C, such as water, to the
inside, and a plurality of port mouths 26 which perform opening
outside from this cavernous portion 25 are formed. The cooling
medium C introduced into the cavernous portion 25 through an
introductory tubing which is not illustrated performs a primary
cooling of the cast member S by cooling the mold 20, and is blown
off from the port mouth 26 to perform a secondary cooling of the
casting S.
[0298] Furthermore, lubricating oil is introduced into a supply
passage 28 via a passage 27 from the exterior, and is supplied to
the inner peripheral surface 20a of the mold 20 via a number of
supply canaliculus 29 branched from the supply passage 28.
[0299] In FIG. 7, "31" denotes an exit of the tundish 21, and "32"
denotes a molten metal inlet.
[0300] According to the horizontal continuous casting apparatus,
the casting rate and cooling rate of the present invention can be
attained, and a cast member having outstanding characteristics,
such as cutting ability, can be manufactured.
[0301] Two kinds of non-hollow members having round cross-section
were manufactured under the casting conditions c and d shown in the
following Table 10.
10 TABLE 10 Casting condition c Casting condition d Molten metal
730.degree. C. 730.degree. C. temperature in tundish Amount of
cooling 8 litter/min. 8 litter/min. water Casting diameter Diameter
of 25 mm Diameter of 10 mm Casting rate 800 mm/min. 3,000 mm/min.
Lubricating oil castor oil castor oil Amount of 0.2 cc/min. 0.2
cc/min. Lubricating oil Diameter of molten 5 mm 5 mm metal
input
[0302] [Metal Mold Casting]
[0303] The cast molds No. IIB-9 and IIB-10, which are comparative
examples, are ingots obtained by the sand-mold type test mold (ISO
mold) under the casting conditions shown in the following Table
11.
[0304] To the cast members No. IIB-1 to IIB-4 and IIB-9, aging of
170.degree. C..times.11 hours was performed, and then scalping
processing was performed to eliminate the surface of 1.5 mm depth,
to thereby obtain test members. To the cast members No. IIB-5 to
IIB-8 and IIB-10, scalping processing was performed to eliminate
the surface of 1.5 mm depth, and then aging of 170.degree.
C..times.11 hours was performed, to thereby obtain test
members.
[0305] The metal texture of each of these test pieces was observed,
and the average DAS, the distribution state of the particle in the
eutectic lamella texture, (the mean particle diameter of the
eutectic Si particle, the number of particles and the area share of
the eutectic Si particles and the second phase particles), the
eutectic lamella texture size (the mean skeleton line length Lm,
the mean width Wm, these ratio L/Wm) were examined. The main points
of the manufacture conditions of each casting example are again
shown in Table 11, the observation results of the metal texture are
shown in Table 11.
11 TABLE 11 Metal texture Distribution state of Eutectic lamella
texture Casting conditions particle Mean Casting Casting Mean
Particle skeleton Mean Casting method, rate Cast Cooling Aging Mean
diam- Area number line width No. Alloy Casting Mm/ diameter rate
Temp. Hours DAS eter share Pieces/ length Wm, (IIB-n) No.
conditions min. mm .degree. C./min. .degree. C. h .mu.m .mu.m %
mm.sup.2 Lm, .mu.m .mu.m L/Wm Inven- tion 1 IIA-30 Vertical, a 150
120 20 170 11 15.9 0.78 3.1 2.7 .times. 10.sup.3 42.4 4.6 9.2 2
Vertical, b 300 53 40 20.4 0.91 2.9 5.9 .times. 10.sup.3 50.6 4.9
10.3 3 Horizontal, d 3,000 10 400 4.9 0.45 3.6 2.9 .times. 10.sup.4
49.5 3.2 15.5 4 Horizontal, c 800 25 100 7.6 0.50 3.0 1.8 .times.
10.sup.4 44.6 3.9 11.4 5 IIA-127 Vertical, a 150 120 20 8.7 1.02
7.5 2.7 .times. 10.sup.4 108.6 4.1 26.5 6 Vertical, b 300 53 40
12.4 1.55 7.7 2.7 .times. 10.sup.4 112.4 5.3 21.2 7 Horizontal, d
3,000 10 400 4.5 0.65 6.9 2.7 .times. 10.sup.4 70.2 4.1 17.1 8
Horizontal, c 800 25 100 7.2 1.01 7.6 2.7 .times. 10.sup.4 88.6 3.7
23.9 Com- par- ative 9 IIA-30 Mold 10 200 0.5 170 11 22.7 6.20 4.2
3.5 .times. 10.sup.3 10.3 2.1 4.9 10 IIA-127 Mold 10 200 0.5 16.2
7.22 9.5 2.5 .times. 10.sup.3 15.5 4.6 3.4 The underlined means the
data falls out of the scope of the invention.
[0306] The underlined means the data falls out of the scope of the
invention.
[0307] About each test piece, the mechanical properties of 0.2%
proof strength, tensile strength, fracture elongation were
measured, and the casting nature, cutting ability, abrasion of a
tool, quality of the finished surface, cutting crack nature and
corrosion resistance were examined by the same method as in the
aforementioned alloy composition test. Furthermore, the existence
and the number of internal defects were also evaluated relatively.
Furthermore, the comprehensive quality as an alloy material was
evaluated. The evaluation was made as the following four grade
relative evaluations.
[0308] .circleincircle.: Excellent
[0309] .largecircle.: Slightly excellent
[0310] .DELTA.: Slightly poor
[0311] X: Very poor
12 TABLE 12 Quality of Cutting Casting Mechanical Productivity
Cutting Tool finished crack Corrosion Internal Overall No. (II B-n)
property Castability ability abrasion surface nature resistance
defect evaluation Invention 1 .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. 2
.circleincircle. .largecircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. .circleincircle.
.largecircle. 3 .largecircle. .largecircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
.circleincircle. .largecircle. 4 .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. 5
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. 6 .largecircle. .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .largecircle.
.circleincircle. .largecircle. 7 .circleincircle. .largecircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .largecircle. 8 .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
.circleincircle. .circleincircle. .circleincircle. .circleincircle.
Comparative 9 .DELTA. .DELTA. X .DELTA. X .DELTA. .DELTA. X X 10 X
.DELTA. X .DELTA. X .DELTA. .DELTA. X X
[0312] From the results of Table 12, it was confirmed that the
aluminum alloy material manufactured by the method of this
invention has an eutectic lamella texture where Si particles are
dispersed finely in the metal texture, and therefore has
outstanding cutting ability (including quality of finished surface
and cutting crack nature) and corrosion resistance.
[0313] C. Aging Treatment and Secondary Forming Processing
[0314] Using the alloys No.IIA-30 and IIA-127 as casting materials,
a non-hollow of a round cross-section with a diameter of 53 mm was
made under the casting conditions b shown in Table 7 by the same
gas pressurization type hot top casting as the aforementioned
example of "A. chemical composition of an aluminum alloy." The
surface portion of the cast non-hollow member of 1.5 mm depth was
eliminated by peeling processing, and then aging is performed under
the conditions shown in Table 13. Furthermore, to the processing
No.IIC-5 to IIC-8 and IIC13 to IIC-16, drawing processing was given
thereto at the temperature shown in Table 13 and the
cross-sectional area reduction ratio. Drawing was performed well in
all processing No.
[0315] About each test piece manufactured, the mechanical
properties of 0.2% proof strength, tensile strength, fracture
elongation were measured, and the cutting ability, abrasion of a
tool, quality of the finished surface, cutting crack nature and
impact property were evaluated. The impact property was examined by
the following method and the examination method of the other items
was performed by the same method as in the aforementioned alloy
compositions examination. The evaluation was made as the following
four grade relative evaluations. In this examination, the
mechanical property was evaluated as relative evaluation.
[0316] .circleincircle.: Excellent
[0317] .largecircle.: Slightly excellent
[0318] .DELTA.: Slightly poor
[0319] X: Very poor
[0320] [Impact Property]
[0321] The metallic material impact test based on JIS Z2202 and JIS
Z2242 was performed, and the impact property was evaluated by the
charpy impact.
13 TABLE 13 Drawing processing Cross- Various characteristics
section Quality Treatment Aging area of Cutting No. Alloy Temp.
Time Temp. reduction Mechanical Cutting Tool finished crack
Corrosion Impact (IIC-n) No. .degree. C. H .degree. C. ratio %
property ability abrasion surface nature resistance property
Invention 1 IIA-30 170 11 -- -- .circleincircle. .circleincircle.
.largecircle. .circleincircle. .circleincircle. .largecircle.
.largecircle. 2 IIA-30 160 6 -- -- .largecircle. .largecircle.
.largecircle. .largecircle. .circleincircle. .largecircle.
.largecircle. 3 IIA-30 160 15 -- -- .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.largecircle. .largecircle. 4 IIA-30 200 7 -- -- .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.largecircle. .largecircle. 5 IIA-30 160 9 Room temp. 5
.circleincircle. .circleincircle. .largecircle. .circleincircle.
.circleincircle. .largecircle. .largecircle. 6 IIA-30 160 8 Room
temp. 10 .circleincircle. .circleincircle. .largecircle.
.circleincircle. .circleincircle. .largecircle. .largecircle. 7
IIA-30 170 7 Room temp. 10 .circleincircle. .circleincircle.
.largecircle. .circleincircle. .circleincircle. .largecircle.
.largecircle. 8 IIA-30 200 4 Room temp. 10 .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.largecircle. .largecircle. 9 IIA-127 170 11 -- -- .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.largecircle. .largecircle. 10 IIA-127 160 6 -- -- .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.largecircle. .largecircle. 11 IIA-127 160 15 -- -- .largecircle.
.largecircle. .largecircle. .largecircle. .circleincircle.
.largecircle. .largecircle. 12 IIA-127 200 7 -- -- .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.largecircle. .largecircle. 13 IIA-127 160 9 Room temp. 5
.circleincircle. .circleincircle. .largecircle. .circleincircle.
.circleincircle. .largecircle. .largecircle. 14 IIA-127 160 8 Room
temp. 10 .circleincircle. .circleincircle. .largecircle.
.circleincircle. .circleincircle. .largecircle. .largecircle. 15
IIA-127 170 7 Room temp. 10 .circleincircle. .circleincircle.
.largecircle. .circleincircle. .circleincircle. .largecircle.
.largecircle. 16 IIA-127 200 4 Room temp. 10 .circleincircle.
.circleincircle. .largecircle. .circleincircle. .circleincircle.
.largecircle. .largecircle. Comparative 17 IIA-30 310 1 -- -- X
.DELTA. .largecircle. .DELTA. .largecircle. .DELTA. .DELTA. 18
IIA-30 160 105 -- -- X .DELTA. .largecircle. .DELTA. .largecircle.
.DELTA. .DELTA. 19 IIA-127 310 -- -- -- X .DELTA. .largecircle.
.DELTA. .largecircle. .DELTA. .DELTA. 20 IIA-127 160 105 -- -- X
.DELTA. .largecircle. .DELTA. .largecircle. .DELTA. .DELTA. In this
Table, the underlined numeral is out of the scope of the
invention.
[0322] In this Table, the underlined numeral is out of the scope of
the invention.
[0323] From the result shown in Table 13, it was confirmed that, by
giving the aging treatment to a cast member under the conditions of
the invention, outstanding mechanical property, cutting ability
(including quality of finished surface and cutting crack nature),
corrosion resistance and impact property can be obtained, and
abrasion of a tool can be suppressed. Furthermore, it was also
confirmed that the secondary forming processing under the
conditions of the invention enables forming processing without
deteriorating various characteristics, especially cutting
ability.
[0324] As mentioned above, since the aluminum alloy material of the
invention is excellent in cutting ability, the member can be
applied to materials of various kinds of member accompanied by
cutting processing. Furthermore, since no toxic Pb is contained,
not bad influence is given to the environment and recycle nature is
also preferable. Therefore, the material is excellent from the
viewpoint of earth environment protection.
[0325] It should be appreciated that the terms and descriptions
herein are not used for limiting the scope of the invention, but
used only for explanatory purposes, and the invention does not
eliminate any feature equivalent to the feature disclosed and
explained herein, and permits any modifications and substitutions
within the scope of the present invention defined by the appended
claims.
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