U.S. patent application number 11/573638 was filed with the patent office on 2009-10-22 for sn-containing copper alloy and method of manufacturing the same.
This patent application is currently assigned to SANBO SHINDO KOGYO KABUSHIKI KAISHA. Invention is credited to Keiichiro Oishi.
Application Number | 20090260727 11/573638 |
Document ID | / |
Family ID | 35839218 |
Filed Date | 2009-10-22 |
United States Patent
Application |
20090260727 |
Kind Code |
A1 |
Oishi; Keiichiro |
October 22, 2009 |
Sn-CONTAINING COPPER ALLOY AND METHOD OF MANUFACTURING THE SAME
Abstract
A Sn-containing copper alloy, contains Sn: 0.01 to 16 mass %,
Zr: 0.001 to 0.049 mass %, P: 0.01 to 0.25 mass %, and Cu:
remainder; satisfying f0=[Cu]-0.5[Sn]-3[P]=61 to 97, f1=[P]/[Zr]
0.5 to 100, f2=3[Sn]/[Zr]=30 to 15000 and f3=3[Sn]/[P]=3 to 2500
(the content of element `a` is represented as [a] mass %). .alpha.
and .gamma.-phases and/or .delta.-phase are included and the total
content of the .alpha. and .gamma.-phases and/or .delta.-phase
reaches 90% or more by area ratio, and the mean grain size of the
macrostructure during melt-solidification is 300 .mu.m or less.
Inventors: |
Oishi; Keiichiro; (Osaka,
JP) |
Correspondence
Address: |
GRIFFIN & SZIPL, PC
SUITE PH-1, 2300 NINTH STREET, SOUTH
ARLINGTON
VA
22204
US
|
Assignee: |
SANBO SHINDO KOGYO KABUSHIKI
KAISHA
Sakai-shi, Osaka
JP
|
Family ID: |
35839218 |
Appl. No.: |
11/573638 |
Filed: |
August 10, 2005 |
PCT Filed: |
August 10, 2005 |
PCT NO: |
PCT/JP05/14699 |
371 Date: |
February 12, 2007 |
Current U.S.
Class: |
148/553 ;
148/433; 148/442; 148/538 |
Current CPC
Class: |
A61P 11/06 20180101;
C22F 1/08 20130101; B22D 27/00 20130101; C22C 9/04 20130101; B22D
21/022 20130101; C22C 30/06 20130101; C22C 9/00 20130101; C22C 1/03
20130101; C22C 30/02 20130101; C22C 1/06 20130101; B22D 21/025
20130101 |
Class at
Publication: |
148/553 ;
148/433; 148/442; 148/538 |
International
Class: |
C22F 1/08 20060101
C22F001/08; C22C 9/02 20060101 C22C009/02; C22C 30/00 20060101
C22C030/00; C22F 1/00 20060101 C22F001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 10, 2004 |
JP |
2004-233952 |
Claims
1. A Sn-containing copper alloy, comprising: Sn: 0.01 to 16 mass %,
Zr: 0.001 to 0.049 mass %, P: 0.01 to 0.25 mass %, and Cu:
remainder, wherein f0=[Cu]-0.5[Sn]-3[P]=61 to 97, f1=[P]/[Zr]=0.5
to 100, f2=3[Sn]/[Zr]=30 to 15000 and f3=3[Sn]/[P]=3 to 2500, where
the content of element `a` is represented as [a] mass % are
satisfied, and wherein .alpha. and .gamma.-phases and
.delta.-phase, or .alpha. and .gamma.-phases or .delta.-phase, are
included and the total content of the .alpha. and .gamma.-phases
and .delta.-phase, or .alpha. and .gamma.-phases or .delta.-phase,
reaches 90% or more by area ratio, and a mean grain size in a
macrostructure during melt-solidification is 300 .mu.m or less.
2. A Sn-containing copper alloy comprising: Sn: 0.01 to 16 mass %,
Zr: 0.001 to 0.049 mass %, P: 0.01 to 0.25 mass %, Zn: 0.01 to 38
mass %, and Cu: remainder, wherein f0=[Cu]-0.5[Sn]-3[P]=61 to 97,
f1=[P]/[Zr]=0.5 to 100, f2=([Zn]+3[Sn])/[Zr]=30 to 15000,
f3=([Zn]+3[Sn])/[P]=3 to 2500 and f4=[Zn]+3[Sn]=10 to 48, wherein
the content of each element `a` is represented as [a] mass % are
satisfied, and wherein the .alpha. and .gamma.-phases and
.delta.-phase, or the .alpha. and .gamma.-phases or .delta.-phase,
are included and the total content of the .alpha. and
.gamma.-phases and .delta.-phase, or the .alpha. and .gamma.-phases
or .delta.-phase, reaches 90% or more by area ratio, and the mean
grain size in the macrostructure during the melt-solidification is
300 .mu.m or less.
3. A Sn-containing copper alloy comprising: Sn: 0.01 to 16 mass %;
Zr: 0.001 to 0.049 mass %; P: 0.01 to 0.25 mass %; one or more
elements selected from Mn: 0.05 to 4 mass %, Al: 0.01 to 3 mass %,
Si: 0.01 to 1.9 mass % and Co: 0.005 to 0.1 mass %; and Cu:
remainder, wherein f0=[Cu]-0.5[Sn]-3[P]+[Mn]-1.8[Al]-3.5[Si]=61 to
97, f1=[P]/[Zr]=0.5 to 100, f2=3[Sn]/[Zr]=30 to 15000, and
f3=3[Sn]/[P]=3 to 2500, wherein the content of each element `a` is
represented as [a] mass %, and [a] =0 for each element `a` that is
not contained in the alloy, are satisfied, and the .alpha. and
.gamma.-phases and .delta.-phase, or .alpha. and .gamma.-phases or
.delta.-phase, are included and the total content of the .alpha.
and .gamma.-phases and .delta.-phase, or .alpha. and .gamma.-phases
or .delta.-phase, reaches 90% or more by area ratio, and the mean
grain size in the macrostructure during melt-solidification is 300
.mu.m or less.
4. A Sn-containing copper alloy comprising: Sn: 0.01 to 16 mass %;
Zr: 0.001 to 0.049 mass %; P: 0.01 to 0.25 mass %; Zn: 0.01 to 38
mass %; one or more elements selected from Mn: 0.05 to 4 mass %,
Al: 0.01 to 3 mass %, Si: 0.01 to 1.9 mass % and Co: 0.005 to 0.1
mass %; and Cu: remainder, wherein
f0=[Cu]-0.5[Sn]-3[P]+[Mn]-1.8[Al]-3.5[Si]=61 to 97, f1=[P]/[Zr]=0.5
to 100, f2=([Zn]+3[Sn])/[Zr]=30 to 15000, f3=([Zn]+3[Sn])/[P]=3 to
2500 and f4=[Zn]+3[Sn]=10 to 48, wherein the content of each
element `a` is represented as [a] mass %, and [a]=0 for each
element `a` that is not contained in the alloy, are satisfied, and
the .alpha. and .gamma.-phases and .delta.-phase, or .alpha. and
.gamma.-phases or .delta.-phase, are included and the total content
of the .alpha. and .gamma.-phases and .delta.-phase, or .alpha. and
.gamma.-phases or .delta.-phase, reaches 90% or more by area ratio,
and the mean grain size in the macrostructure during
melt-solidification is 300 .mu.m or less.
5. (canceled)
6. A Sn-containing copper alloy comprising: Sn: 0.01 to 16 mass %;
Zr: 0.001 to 0.049 mass %; P: 0.01 to 0.25 mass %; Zn: 0.01 to 38
mass %; one or more elements selected from As: 0.02 to 0.2 mass %,
Sb: 0.02 to 0.2 mass % and Mg: 0.001 to 0.2 mass %; and Cu:
remainder, wherein
f0=[Cu]-0.5[Sn]-3[P]-0.5([As]+[Sb])+[Mg]+[Mn]-1.8[Al]-3.5[Si]=61 to
97, f1=[P]/[Zr]=0.5 to 100, f2=([Zn]+3[Sn])/[Zr]=30 to 15000,
f3=([Zn]+3[Sn])/[P]=3 to 2500 and f4=[Zn]+3[Sn]=10 to 48, wherein
the content of each element `a` is represented as [a] mass %, and
[a]=0 for each element `a` that is not contained in the alloy, are
satisfied, and the .alpha. and .gamma.-phases and .delta.-phase, or
.alpha. and .gamma.-phases or .delta.-phase, are included and the
total content of the .alpha. and .gamma.-phases and .delta.-phase,
or .alpha. and .gamma.-phases or .delta.-phase, reaches 90% or more
by area ratio, and the mean grain size in the macrostructure during
melt-solidification is 300 .mu.m or less.
7. The Sn-containing copper alloy according to any one of claims 1
to 4, 6, or 23, comprising: Fe and Ni, or Fe or Ni, as inevitable
impurities, wherein when either of Fe or Ni is included, the
content thereof is limited to be 0.25 mass % or less, and when both
of Fe and Ni are included, the total content thereof is limited to
be 0.3 mass % or less.
8. The Sn-containing copper alloy according to any one of claims 1
to 4, 6, or 23, wherein a primary crystal is .alpha.-phase during
melt-solidification.
9. The Sn-containing copper alloy according to any one of claims 1
to 4, 6, or 23, wherein peritectic reaction is generated during
melt-solidification.
10. The Sn-containing copper alloy according to any one of claims 1
to 4, 6, or 23, wherein dendrite network is divided in crystal
structure and a two-dimensional shape of grain is circular,
substantially circular, oval, cross-like, acicular or polygonal
during melt-solidification.
11. The Sn-containing copper alloy according to any one of claims 1
to 4, 6, or 23, wherein the .alpha.-phase in a matrix is minutely
divided, and the .delta. and .gamma.-phases or high
Sn-concentration parts generated by segregation are distributed
uniformly in the matrix.
12. The Sn-containing copper alloy according to any one of claims 1
to 4, 6, or 23, wherein, in a semi-solid metal state including 30
to 80% of solid phase, at least the dendrite network is divided in
crystal structure and the two-dimensional shape of the solid phase
is circular, substantially circular, oval, cross-like, acicular or
polygonal.
13. The Sn-containing copper alloy according to claim 12, wherein,
in the semi-solid metal state including 60% of the solid phase, a
mean grain size of the solid phase is 150 .mu.m or less and a mean
maximum grain length of the solid phase is 200 .mu.m or less, or
the mean grain size of the solid phase is 150 .mu.m or less or the
mean maximum grain length of the solid phase is 200 .mu.m or
less.
14. The Sn-containing copper alloy according to any one of claims 1
to 4, 6, or 23, wherein the copper alloy is a casting product
obtained in a casting process or a plastic-worked product, wherein
the casting product is plastic-worked additionally one or more
times.
15. The Sn-containing copper alloy according to claim 14, wherein
the casting product is a wire, rod or hollow bar cast by horizontal
continuous casting method, upward method or upcast method.
16. The Sn-containing copper alloy according to claim 14, wherein
the casting product is a casting product, semi-solid metal casting
product, semi-solid metal molding product, molten alloy forging
product or die casing molding product.
17. The Sn-containing copper alloy according to claim 14, wherein
the plastic-worked product is a hot extruding product, hot forging
product or hot rolling product.
18. The Sn-containing copper alloy according to claim 14, wherein
the plastic-worked product is a cold rolling product or cold
drawing product.
19. The Sn-containing copper alloy according to claim 14, wherein
the casting product is a gear, a worm gear, a bearing, a bush, an
impeller, common mechanical parts, a metal fitting for water
contact or a joint.
20. The Sn-containing copper alloy according to claim 14, wherein
the plastic-worked product is electronicelectric device spring,
switch, lead frame, connector, bellow, fuse grip, bush, relay,
gear, cam, joint, flange, bearing, machine screw, bolt, nut, metal
eyelet, heat exchanger pipe, heat exchanger, metallic mesh, sea
net, breeding net, fish net, header material, washer, seawater
condenser tube, ship parts shaft, seawater intake of a ship or
metal fitting for water contact.
21. A method of manufacturing the Sn-containing copper alloy
according to any one of claims 1 to 4, or 6, wherein, in a casting
process, Zr is added in a form of copper alloy containing Zr in
order to prevent Zr from being added in a form of oxide or sulfide,
or oxide and sulfide.
22. The method of manufacturing the Sn-containing copper alloy
according to claim 21, wherein the copper alloy containing Zr is
one of Cu--Zr alloy, Cu--Zn--Zr alloy, Cu--Zr alloy, to which one
or more element selected from P, Mg, Al, B, Sn and Mn are added,
and Cu--Zn--Zr alloy, to which one or more element selected from P,
Mg, Al, B, Sn and Mn are added.
23. A Sn-containing copper alloy comprising: Sn: 0.01 to 16 mass %;
Zr: 0.001 to 0.049 mass %; P: 0.01 to 0.25 mass %; Zn: 0.01 to 38
mass %; one or more elements selected from As: 0.02 to 0.2 mass %,
Sb: 0.02 to 0.2 mass % and Mg: 0.001 to 0.2 mass %; one or more
elements selected from Mn: 0.05 to 4 mass %, Al: 0.01 to 3 mass %,
Si: 0.01 to 1.9 mass % and Co: 0.005 to 0.1 mass %; and Cu:
remainder, wherein
f0=[Cu]-0.5[Sn]-3[P]-0.5([As]+[Sb])+[Mg]+[Mn]-1.8[Al]-3.5[Si]=61 to
97, f1=[P]/[Zr]=0.5 to 100, f2=([Zn]+3[Sn])/[Zr]=30 to 15000,
f3=([Zn]+3[Sn])/[P]=3 to 2500 and f4=[Zn]+3[Sn]=10 to 48, wherein
the content of each element `a` is represented as [a] mass %, and
[a]=0 for each element `a` that is not contained in the alloy, are
satisfied, and the .alpha. and .gamma.-phases and .delta.-phase, or
the .alpha. and .gamma.-phases or .delta.-phase, are included and
the total content of the .alpha. and .gamma.-phases and
.delta.-phase, or the .alpha. and .gamma.-phases or .delta.-phase,
reaches 90% or more by area ratio, and the mean grain size in the
macrostructure during melt-solidification is 300 mm or less.
24. The Sn-containing copper alloy according to claim 7, wherein
the copper alloy is a casting product obtained in a casting process
or a plastic-worked product, wherein the casting product is
plastic-worked additionally one or more times.
25. The Sn-containing copper alloy according to claim 9, wherein
the copper alloy is a casting product obtained in a casting process
or a plastic-worked product, wherein the casting product is
plastic-worked additionally one or more times.
26. The Sn-containing copper alloy according to claim 10, wherein
the copper alloy is a casting product obtained in a casting process
or a plastic-worked product, wherein the casting product is
plastic-worked additionally one or more times.
27. The Sn-containing copper alloy according to claim 11, wherein
the copper alloy is a casting product obtained in a casting process
or a plastic-worked product, wherein the casting product is
plastic-worked additionally one or more times.
28. The Sn-containing copper alloy according to claim 25, wherein
the casting product is a wire, rod or hollow bar cast by horizontal
continuous casting method, upward method or upcast method.
29. The Sn-containing copper alloy according to claim 25, wherein
the casting product is a casting product, semi-solid metal casting
product, semi-solid metal molding product, molten alloy forging
product or die casing molding product.
30. The Sn-containing copper alloy according to claim 25, wherein
the plastic-worked product is a hot extruding product, hot forging
product or hot rolling product.
31. The Sn-containing copper alloy according to claim 25, wherein
the plastic-worked product is a cold rolling product or cold
drawing product.
32. The Sn-containing copper alloy according to claim 25, wherein
the casting product is a gear, a worm gear, a bearing, a bush, an
impeller, common mechanical parts, a metal fitting for water
contact or a joint.
33. The Sn-containing copper alloy according to claim 25, wherein
the plastic-worked product is electronic electric device spring,
switch, lead frame, connector, bellow, fuse grip, bush, relay,
gear, cam, joint, flange, bearing, machine screw, bolt, nut, metal
eyelet, heat exchanger pipe, heat exchanger, metallic mesh, sea
net, breeding net, fish net, header material, washer, seawater
condenser tube, ship parts shaft, seawater intake of a ship or
metal fitting for water contact.
34. The Sn-containing copper alloy according to claim 14, wherein
the casting product includes a semi-solid metal casting
product.
35. The Sn-containing copper alloy according to claim 27, wherein
the plastic-worked product is a cold rolling product or cold
drawing product.
36. The Sn-containing copper alloy accoring to claim 27, wherein
the plastic-worked product is electronicelectric device spring,
switch, lead frame, connector, bellow, fuse grip, bush, relay,
gear, cam, joint, flange, bearing, machine screw, bolt, nut, metal
eyelet, heat exchanger pipe, heat exchanger, metallic mesh, sea
net, breeding net, fish net, header material, washer, seawater
condenser tube, ship parts shaft, seawater intake of a ship or
metal fitting for water contact.
Description
TECHNICAL FIELD
[0001] The present invention relates to a Sn-containing copper
alloy, the castability, hotcold workability or the like of which
are improved by refining the grains.
BACKGROUND ART
[0002] Generally, a phosphor bronze or the like defined in C5111,
C5102, C5191 and C5212 of JIS H3110 or JIS H3270; CAC502A and
CAC502B of JIS H5120; C4250 and C4430 of JIS H3100 are well known
as a Sn-containing copper alloy. However, such copper alloy has
inferior castability, hotcold workability or the like, and thus can
be used only in limited fields. The above disadvantages are due to
Sn, a low melting point metal, contained in the copper alloys,
particularly, to the macro-structural segregation of Sn.
[0003] As an effective method of preventing such macro-structural
segregation of Sn, it can be considered to refine the grains of the
copper alloys.
[0004] Generally, the grains of the copper alloys are refined as
follows: (A) the grains are refined during the melt-solidification
of the copper alloys, or (B) the grains are refined by deforming,
such as rolling or the like, or heating the melt-solidified copper
alloys (ingot such as slurry or the like, casting product such as
die casting or the like, solid metal casting or the like), in which
stored energy such as distortion energy or the like acts as a
driving force. In any case, Zr is known as an effective element for
the grain refinement.
[0005] However, in the case of (A), the action of Zr to refine the
grains during the melt-solidification significantly depends on the
other elements and the amount thereof, therefore, it is hard to
achieve a desired level of grain refinement. Consequently, the
method in the case of (B) is widely used, that is, melt-solidified
ingot, casting product or the like is provided with heat treatment
and then distorted in order to refine the grains.
[0006] For example, JP-B-38-20467 discloses that the grains are
refined further as the content of Zr increases on the basis of an
investigation, in which copper alloys containing Zr, P and Ni are
solution-treated and then cold-worked at the processing rate of
75%, showing the mean grain sizes 280 .mu.m (no Zr contained), 170
.mu.m (0.05 mass % of Zr contained), 50 .mu.m (0.13 mass % of Zr
contained), 29 .mu.m (0.22 mass % of Zr contained) and 6 .mu.m
(0.89 mass % of Zr contained). In addition, JP-B-38-20467 proposes
that the content of Zr be in the range of 0.05 to 0.3 mass % in
order to avoid bad influence from the excessive content of Zr.
[0007] Furthermore, JP-A-2004-233952 discloses that, if copper
alloys containing 0.15 to 0.5 mass % of Zr are provided with
solution treatment and deforming process for distorting the alloys
after casting, the mean grain sizes are reduced to be about 20
.mu.m or less.
[0008] However, if the copper alloys are solution-treated and
deformed after casting to refine the grains like the method in the
case of (B), the manufacturing cost will rise. In addition, there
can be cases where the deforming process for distorting the copper
alloys is hardly performed due to the shapes of the copper alloy
casting products. Therefore, it is preferable that the grains be
refined during the melt-solidification of copper alloy by the
method in the case of (A). However, in the case of (A), since the
action of Zr significantly depends on the other elements and the
content thereof as described above, the grains are not necessarily
refined as much as the content of Zr increases. In addition, since
Zr has an extremely high affinity to oxygen, Zr is highly likely to
be an oxide when melted and added in the air, thereby reducing the
yield of Zr. Consequently, even when a casting product contains a
slight amount of Zr, a great amount of Zr needs to be charged
during pouring. Meanwhile, if too many oxides are generated during
melting, it is highly likely that the oxides enter the molten alloy
during the pouring, thereby easily generating casting defects in
the casting products. Even though the melting or casting can be
carried out under vacuum or inert gas atmosphere in order to
prevent the oxide from being generated, the manufacturing cost
would significantly rise in this case. In addition, since Zr is an
expensive element, it is preferable from an economic viewpoint that
the adding amount of Zr be as low as possible.
[0009] As a result, it is highly demanded to develop a method to
reduce the mean grain size during the melt-solidification while the
content of Zr remains as low as possible.
DISCLOSURE OF THE INVENTION
[0010] The invention has been finalized in terms of the drawbacks
inherent to the related arts, and it is an advantage of an aspect
of the invention to provide a Sn-containing copper alloy, in which
grains are refined and the macro-structural segregation of Sn
seldom occurs so as to exclude the inherent drawbacks such as the
deterioration of castabiliy, hotcold workability or the like with
no damages on the effect of Sn (the improvement of corrosion
resistance, strength or the like), and a method of manufacturing
the same.
[0011] In order to achieve the advantage, the invention proposes,
particularly, the following Sn-containing copper alloy and method
of manufacturing the same.
[0012] That is, according to a first aspect of the invention, the
invention proposes a Sn-containing copper alloy (hereinafter
referred to as `first copper alloy`) containing Sn: 0.01 to 16 mass
% (preferably 0.3 to 15 mass %, more preferably 0.5 to 13 mass %,
further more preferably 0.7 to 11 mass %, and most preferably 0.8
to 3.5 mass %); Zr: 0.001 to 0.049 mass % (preferably 0.003 to
0.039 mass %, more preferably 0.0055 to 0.029 mass %, further more
preferably 0.0075 to 0.024 mass %, and most preferably 0.0085 to
0.019 mass %); P: 0.01 to 0.25 mass % (preferably 0.02 to 0.18 mass
%, more preferably 0.025 to 0.14 mass %, further more preferably
0.03 to 0.12 mass %, and most preferably 0.035 to 0.11 mass %); and
Cu: a remainder, and satisfying the following conditions (1) to
(6). The first copper alloy is preferable to further satisfy the
following conditions (8) to (13) in addition to the conditions (1)
to (6).
[0013] According to a second aspect of the invention, the invention
proposes a Sn-containing copper alloy (hereinafter referred to as
`second copper alloy`) further containing one or more elements
selected from Mn, Al, Si and Co in addition to the components of
the first copper alloy, that is, contains Sn: 0.01 to 16 mass %
(preferably 0.3 to 15 mass %, more preferably 0.5 to 13 mass %,
further more preferably 0.7 to 11 mass %, and most preferably 0.8
to 3.5 mass %); Zr: 0.001 to 0.049 mass % (preferably 0.003 to
0.039 mass %, more preferably 0.0055 to 0.029 mass %, further more
preferably 0.0075 to 0.024 mass %, and most preferably 0.0085 to
0.019 mass %); P: 0.01 to 0.25 mass % (preferably 0.02 to 0.18 mass
%, more preferably 0.025 to 0.14 mass %, further more preferably
0.03 to 0.12 mass %, and most preferably 0.035 to 0.11 mass %); one
or more elements selected from Mn: 0.05 to 4 mass % (preferably
0.03 to 3.5 mass % and more preferably 0.05 to 3 mass %), Al: 0.01
to 3 mass % (preferably 0.05 to 2.5 mass % and more preferably 0.1
to 2.3 mass %), Si: 0.01 to 1.9 mass % (preferably 0.02 to 1.5 mass
% and more preferably 0.05 to 1.2 mass %) and Co: 0.005 to 0.1 mass
% (preferably 0.01 to 0.05 mass % and more preferably 0.01 to 0.03
mass %); and Cu: the remainder, and satisfying the following
conditions (1) to (6). The second copper alloy is preferable to
further satisfy the following conditions (8) to (13) in addition to
the conditions (1) to (6).
[0014] According to a third aspect of the invention, the invention
proposes a Sn-containing copper alloy (hereinafter referred to as
`third copper alloy`) further containing one or more elements
selected from As, Sb and Mg in addition to the components of the
first copper alloy, that is, containing Sn: 0.01 to 16 mass %
(preferably 0.3 to 15 mass %, more preferably 0.5 to 13 mass %,
further more preferably 0.7 to 11 mass %, and most preferably 0.8
to 3.5 mass %); Zr: 0.001 to 0.049 mass % (preferably 0.003 to
0.039 mass %, more preferably 0.0055 to 0.029 mass %, further more
preferably 0.0075 to 0.024 mass %, and most preferably 0.0085 to
0.019 mass %); P: 0.01 to 0.25 mass % (preferably 0.02 to 0.18 mass
%, more preferably 0.025 to 0.14 mass %, further more preferably
0.03 to 0.12 mass %, and most preferably 0.035 to 0.11 mass %); one
or more elements selected from As: 0.02 to 0.2 mass % (preferably
0.03 to 0.12 mass %), and Sb: 0.02 to 0.2 mass % (preferably 0.03
to 0.12 mass %) and Mg: 0.001 to 0.2 mass % (preferably 0.002 to
0.15 mass % and more preferably 0.005 to 0.1 mass %); and Cu: the
remainder, and satisfying the following conditions (1) to (6). The
third copper alloy is preferable to further satisfy the following
conditions (8) to (13) in addition to the conditions (1) to
(6).
[0015] According to a fourth aspect of the invention, the invention
proposes a Sn-containing copper alloy (hereinafter referred to as
`fourth copper alloy`) further containing one or more elements
selected from Mn, Al, Si and Co; and one or more elements selected
from As, Sb and Mg in addition to the components of the first
copper alloy, that is, containing Sn: 0.01 to 16 mass % (preferably
0.3 to 15 mass %, more preferably 0.5 to 13 mass %, further more
preferably 0.7 to 11 mass %, and most preferably 0.8 to 3.5 mass
%); Zr: 0.001 to 0.049 mass % (preferably 0.003 to 0.039 mass %,
more preferably 0.0055 to 0.029 mass %, further more preferably
0.0075 to 0.024 mass %, and most preferably 0.0085 to 0.019 mass
%); P: 0.01 to 0.25 mass % (preferably 0.02 to 0.18 mass %, more
preferably 0.025 to 0.14 mass %, further more preferably 0.03 to
0.12 mass %, and most preferably 0.035 to 0.11 mass %); one or more
elements selected from As: 0.02 to 0.2 mass % (preferably 0.03 to
0.12 mass %), and Sb: 0.02 to 0.2 mass % (preferably 0.03 to 0.12
mass %) and Mg: 0.001 to 0.2 mass % (preferably 0.002 to 0.15 mass
%, more preferably 0.005 to 0.1 mass %); one or more elements
selected from Mn: 0.05 to 4 mass % (preferably 0.03 to 3.5 mass %
and more preferably 0.05 to 3 mass %), Al: 0.01 to 3 mass %
(preferably 0.05 to 2.5 mass % and more preferably 0.1 to 2.3 mass
%), Si: 0.01 to 1.9 mass % (preferably 0.02 to 1.5 mass % and more
preferably 0.05 to 1.2 mass %) and Co: 0.005 to 0.1 mass %
(preferably 0.01 to 0.05 mass % and more preferably 0.01 to 0.03
mass %); and Cu: the remainder, and satisfying the following
conditions (1) to (6). The fourth copper alloy is preferable to
further satisfy the following conditions (8) to (13) in addition to
the conditions (1) to (6).
[0016] According to a fifth aspect of the invention, the invention
proposes a Sn-containing copper alloy (hereinafter referred to as
`fifth copper alloy`) further containing Zn in addition to the
components of the first copper alloy, that is, containing Sn: 0.01
to 16 mass % (preferably 0.3 to 15 mass %, more preferably 0.5 to
13 mass %, further more preferably 0.7 to 11 mass %, and most
preferably 0.8 to 3.5 mass %); Zr: 0.001 to 0.049 mass %
(preferably 0.003 to 0.039 mass %, more preferably 0.0055 to 0.029
mass %, further more preferably 0.0075 to 0.024 mass %, and most
preferably 0.0085 to 0.019 mass %); P: 0.01 to 0.25 mass %
(preferably 0.02 to 0.18 mass %, more preferably 0.025 to 0.14 mass
%, further more preferably 0.03 to 0.12 mass %, and most preferably
0.035 to 0.11 mass %); Zn: 0.01 to 38 mass % (preferably 10 to 37
mass %, more preferably 15 to 36 mass %, and most preferably 20 to
34 mass %); and Cu: the remainder, and satisfying the following
conditions (1) to (7). The fifth copper alloy is preferable to
further satisfy the following conditions (8) to (13) in addition to
the conditions (1) to (7).
[0017] According to a sixth aspect of the invention, the invention
proposes a Sn-containing copper alloy (hereinafter referred to as
`sixth copper alloy`) further containing one or more elements
selected from Mn, Al, Si and Co in addition to the components of
the fifth copper alloy, that is, containing Sn: 0.01 to 16 mass %
(preferably 0.3 to 15 mass %, more preferably 0.5 to 13 mass %,
further more preferably 0.7 to 11 mass %, and most preferably 0.8
to 3.5 mass %); Zr: 0.001 to 0.049 mass % (preferably 0.003 to
0.039 mass %, more preferably 0.0055 to 0.029 mass %, further more
preferably 0.0075 to 0.024 mass %, and most preferably 0.0085 to
0.019 mass %); P: 0.01 to 0.25 mass % (preferably 0.02 to 0.18 mass
%, more preferably 0.025 to 0.14 mass %, further more preferably
0.03 to 0.12 mass %, and most preferably 0.035 to 0.11 mass %); Zn:
0.01 to 38 mass % (preferably 10 to 37 mass %, more preferably 15
to 36 mass %, and most preferably 20 to 34 mass %); one or more
elements selected from Mn: 0.05 to 4 mass % (preferably 0.03 to 3.5
mass % and more preferably 0.05 to 3 mass %), Al: 0.01 to 3 mass %
(preferably 0.05 to 2.5 mass % and more preferably 0.1 to 2.3 mass
%), Si: 0.01 to 1.9 mass % (preferably 0.02 to 1.5 mass % and more
preferably 0.05 to 1.2 mass %) and Co: 0.005 to 0.1 mass %
(preferably 0.01 to 0.05 mass % and more preferably 0.01 to 0.03
mass %); and Cu: the remainder, and satisfying the following
conditions (1) to (7). The sixth copper alloy is preferable to
further satisfy the following conditions (8) to (13) in addition to
the conditions (1) to (7).
[0018] According to a seventh aspect of the invention, the
invention proposes a Sn-containing copper alloy (hereinafter
referred to as `seventh copper alloy`) further containing one or
more elements selected from As, Sb and Mg in addition to the
components of the fifth copper alloy, that is, containing Sn: 0.01
to 16 mass % (preferably 0.3 to 15 mass %, more preferably 0.5 to
13 mass %, further more preferably 0.7 to 11 mass %, and most
preferably 0.8 to 3.5 mass %); Zr: 0.001 to 0.049 mass %
(preferably 0.003 to 0.039 mass %, more preferably 0.0055 to 0.029
mass %, further more preferably 0.0075 to 0.024 mass %, and most
preferably 0.0085 to 0.019 mass %); P: 0.01 to 0.25 mass %
(preferably 0.02 to 0.18 mass %, more preferably 0.025 to 0.14 mass
%, further more preferably 0.03 to 0.12 mass %, and most preferably
0.035 to 0.11 mass %); Zn: 0.01 to 38 mass % (preferably 10 to 37
mass %, more preferably 15 to 36 mass %, and most preferably 20 to
34 mass$); one or more elements selected from As: 0.02 to 0.2 mass
% (preferably 0.03 to 0.12 mass %), and Sb: 0.02 to 0.2 mass %
(preferably 0.03 to 0.12 mass %) and Mg: 0.001 to 0.2 mass %
(preferably 0.002 to 0.15 mass %, more preferably 0.005 to 0.1 mass
%); and Cu: the remainder, and satisfying the following conditions
(1) to (7). The seventh copper alloy is preferable to further
satisfy the following conditions (8) to (13) in addition to the
conditions (1) to (7).
[0019] According to an eighth aspect of the invention, the
invention proposes a Sn-containing copper alloy (hereinafter
referred to as `eighth copper alloy`) further containing one or
more elements selected from Mn, Al, Si and Co; and one or more
elements selected from As, Sb and Mg in addition to the components
of the fifth copper alloy, that is, containing Sn: 0.01 to 16 mass
% (preferably 0.3 to 15 mass %, more preferably 0.5 to 13 mass %,
further more preferably 0.7 to 11 mass %, and most preferably 0.8
to 3.5 mass %); Zr: 0.001 to 0.049 mass % (preferably 0.003 to
0.039 mass %, more preferably 0.0055 to 0.029 mass %, further more
preferably 0.0075 to 0.024 mass %, and most preferably 0.0085 to
0.019 mass %); P: 0.01 to 0.25 mass % (preferably 0.02 to 0.18 mass
%, more preferably 0.025 to 0.14 mass %, further more preferably
0.03 to 0.12 mass %, and most preferably 0.035 to 0.11 mass %); Zn:
0.01 to 38 mass % (preferably 10 to 37 mass %, more preferably 15
to 36 mass %, and most preferably 20 to 34 mass %); one or more
elements selected from Mn: 0.05 to 4 mass % (preferably 0.03 to 3.5
mass % and more preferably 0.05 to 3 mass %), Al: 0.01 to 3 mass %
(preferably 0.05 to 2.5 mass % and more preferably 0.1 to 2.3 mass
%), Si: 0.01 to 1.9 mass % (preferably 0.02 to 1.5 mass % and more
preferably 0.05 to 1.2 mass %) and Co: 0.005 to 0.1 mass %
(preferably 0.01 to 0.05 mass % and more preferably 0.01 to 0.03
mass %); one or more elements selected from As: 0.02 to 0.2 mass %
(preferably 0.03 to 0.12 mass %), and Sb: 0.02 to 0.2 mass %
(preferably 0.03 to 0.12 mass %) and Mg: 0.001 to 0.2 mass %
(preferably 0.002 to 0.15 mass % and more preferably 0.005 to 0.1
mass %); and Cu: the remainder, and satisfying the following
conditions (1) to (7). The eighth copper alloy is preferable to
further satisfy the following conditions (8) to (13) in addition to
the conditions (1) to (7).
[0020] Meanwhile, in the following description, the content of
element `a` is denoted by [a] and expressed in a unit of `mass %`.
For example, the content of Cu is expressed as [Cu] mass %.
[0021] (1)
f0=[Cu]-0.5[Sn]-3[P]-0.5([As]+[Sb])+[Mg]+[Mn]-1.8[Al]-3.5[Si]=6- 1
to 97 (preferably 62.5 to 90, more preferably 63.5 to 88 and most
preferably 65 to 75). Meanwhile, in f0, an element `a`, not
contained in the copper alloy, is denoted by [a]=0. For example,
the first copper alloy satisfies f0=[Cu]-0.5[Sn]-3[P].
[0022] (2) f1=[P]/[Zr]=0.5 to 100 (preferably 0.8 to 25, more
preferably 1.1 to 16, and most preferably 1.5 to 12).
[0023] (3) f2=([Zn]+3[Sn])/[Zr]=30 to 15000 (preferably 300 to
7000, more preferably 650 to 5000 and most preferably 1000 to
3000). Meanwhile, in f2, an element `a`, not contained in the
copper alloy, is denoted by [a]=0. For example, for the first to
fourth copper alloys not containing Zn, f2=3[Sn]/[Zr].
[0024] (4) f3=([Zn]+3[Sn])/[P]=3 to 2500 (preferably 60 to 1600,
more preferably 120 to 1200, and most preferably 200 to 800).
Meanwhile, in f3, an element `a`, not contained in the copper
alloy, is denoted by [a]=0. For example, the first to four copper
alloys containing no Zn satisfy f3=3[Sn]/[P].
[0025] (5) .alpha. phase and, .gamma. and/or .delta.-phases are
contained, and the total content of .alpha. phase and, .gamma.
and/or .delta.-phases occupy 90% or more (preferably 98% or more,
and more preferably 99% or more) of the total area of the copper
alloy. Meanwhile, the content of each phase, that is, area ratio,
is measured by image analysis, more specifically, by expressing the
structure of the copper alloy, 200 times magnified by an optical
microscope, in the binary system with an image processing software
`WinROOF` (manufactured by Tech-Jam Co., Ltd.). The content of each
phase is an average value of the area ratios measured in three
different fields.
[0026] (6) The mean grain size of the macrostructure during
melt-solidification is 300 .mu.m or less (preferably 200 .mu.m or
less, more preferably 100 .mu.m or less and the mean grain size of
the microstructure is 60 .mu.m or less). Herein, the mean grain
size of the macrostructure (or microstructure) during the
melt-solidification represents the average value of the grain size
of the macrostructure (or microstructure) when no deforming process
or heat treatment is carried out on the copper alloy
melt-solidified by casting (including casting by various common
casting methods such as permanent mold casting, sand casting,
horizontal continuous casting, upward (upcast), semi-solid metal
casting, semi-solid metal forging, melt-solidification forging or
the like) or either welding or fusing. Meanwhile, in this
description, `casting` or `casting product` represents a product,
all or part of which is melted and solidified, for example,
beginning from ingot, slab and billet for rolling or extruding,
sand casting product, permanent mold casting product, low-pressure
casting product, die casting, lost wax, semi-solid metal casting
(for example, thixo-casting or rheo-casting) semi-solid metal
forming product, squeeze, centrifugal casting, continuous casting
product (for example, rod, hollow rod, irregular shape rod,
irregular shape hollow rod, coil, wire or the like manufactured by
horizontal continuous casting, upward or upcast) and casting
product manufactured by melt forging (direct forging), metallizing,
build-up spraying, lining and overlay. In addition, welding can be
considered a sort of casting in a broad sense, since, in the
welding, part of mother materials are melted and solidified so as
to join the mother materials.
[0027] (7) f4=[Zn]+3[Sn]=10 to 48 (preferably 15 to 45, more
preferably 20 to 40, and most preferably 25 to 38).
[0028] (8) A primary crystal during the melt-solidification is
.alpha.-phase.
[0029] (9) Peritectic reaction occurs during the
melt-solidification.
[0030] (10) During the melt-solidification, dendrite network is
divided in the crystal structure, and two-dimensional shape of the
crystal grains is circular, substantially circular, oval,
cross-like, acicular or polygonal.
[0031] (11) .alpha.-phase in the matrix is divided minutely, and
.delta.-phase, .gamma.-phase or high Sn-concentration part
generated by segregation is distributed uniformly in the
matrix.
[0032] (12) In a semi-solid metal state, in which the ratio of
solid phase reaches 30 to 80%, at least dendrite network is divided
in the crystal structure, and the two-dimensional shape of the
solid phase is circular, substantially circular, oval, cross-like
or polygonal.
[0033] (13) In a semi-solid metal state, in which the ratio of the
solid phase reaches 60%, the mean grain size of the solid phase is
150 .mu.m or less (preferably 100 .mu.m or less, more preferably 50
.mu.m or less, and most preferably 40 .mu.m or less), and/or the
mean maximum length of the solid phase is 200 .mu.m or less
(preferably 150 .mu.m or less, more preferably 100 .mu.m or less,
and most preferably 80 .mu.m or less).
[0034] In addition, in the first to eighth copper alloys, Cu is a
main element of the copper alloys composing the casting products,
and as the content of Cu increases, {circle around (1)}
.alpha.-phase is easily obtained, {circle around (2)} the corrosion
resistance (dezincification corrosion resistance and stress
corrosion cracking resistance) improves, and {circle around (3)}
mechanical properties improve. However, since the excessive content
of Cu impedes the grain refinement, the content of Cu composes the
remainder. Furthermore, while depending on the proportion of Cu to
Sn (and Zn), it is preferable that the content of Cu be in the
range having the minimum value, at which the copper alloy can
secure more stable corrosion resistance and erosion resistance, and
the maximum value, at which the copper alloy can secure more stable
strength and wear resistance. Still furthermore, it is required to
consider the relationship with the other elements in order to
refine the grains. Consequently, the content of Cu is required to
compose the remainder and to satisfy the condition (1). That is,
the contents of Cu and the other elements have to meet
f0=[Cu]-0.5[Sn]-3[P]-0.5([As]+[Sb])+[Mg]+[Mn]-1.8[Al]-3.5[Si]=61 to
97, preferably 62.5 to 90, more preferably 63.5 to 88, and most
preferably 65 to 75. Meanwhile, the minimum value of f0 is also
related with whether the primary crystal is .alpha.-phase, and the
maximum value of f0 is also related with the peritectic
reaction.
[0035] In the first to eighth copper alloys, Sn is contained mainly
to improve the corrosion resistance. If 0.01 mass % or more of Sn
is added, Sn can improve the corrosion resistance, erosion
resistance, wear resistance and strength. However, the above effect
saturates when the adding content of Sn reaches 16 mass %, and the
ductility and castability deteriorate inversely if more than 16
mass % of Sn is added even in the presence of Zr and P, thereby
causing casting defects such as crack, shrinkage cavity, porosity
or the like. In addition, Sn widens the composition range capable
of generating peritectic reaction (an effective method to refine
the grains during the melt-solidification), and, practically,
peritectic reaction can occur throughout the wide concentration
range of Cu as the content of Sn increases. Considering the above
facts, the content of Sn is defined as preferably 0.3 mass % or
more, more preferably 0.5 mass % or more, further more preferably
0.7 mass % or more, and most preferably 0.8 mass % or more. On the
other hand, while depending on the proportion of Sn to Cu and Zn,
if the content of Sn exceeds 16 mass %, .delta.-phase (and
.gamma.-phase), a hard phase with the Sn-concentration higher than
that of mother phase (.alpha.-phase), is generated excessively
(exceeding 20% by area ratio), thereby causing selective corrosion
of the phase and, consequently, impairing the corrosion resistance.
Furthermore, while depending on the proportion of Sn to Cu (Sn to
Cu and Zn in the cases of the fifth to eighth copper alloys), if
the concentration of Sn is too high, Sn is segregated too much, and
the solidification temperature range is widened as the adding
amount of Sn increases, thereby impairing the castability.
Considering the above facts, the content of Sn needs to be defined
as 0.01 to 16 mass %, preferably 0.3 to 15 mass %, more preferably
0.5 to 13 mass %, further more preferably 0.7 to 11 mass %, and
most preferably 0.8 to 3.5 mass %. If the content of Sn is in the
above range, the content of .delta.-phase (and .gamma.-phase) can
remain at a proper level (20% or less by area ratio).
[0036] In the first to eighth copper alloys, Zr and P are added
together to refine the grains of the copper alloy, particularly,
during the melt-solidification. That is, even though either Zr or P
alone can refine the grains slightly like the other additives, if
added together, Zr and P can refine the grains effectively.
[0037] With respect to Zr, even though the grains can be refined
when 0.001 mass % or more of Zr is contained, the grains can be
refined remarkably at the content of 0.003 mass % or more, more
remarkably at the content of 0.0055 mass %, further more remarkably
at the content of 0.0075 mass % or more, and most remarkably at the
content of 0.0085 mass % or more. With respect to P, even though
the grains can be refined when 0.01 mass % or more of P is
contained, the grains can be refined remarkably at the content of
0.02 mass % or more, more remarkably at the content of 0.025 mass
%, further more remarkably at the content of 0.03 mass % or more,
and most remarkably at the content of 0.035 mass % or more.
[0038] On the other hand, when the content of Zr reaches 0.049 mass
% and the content of P reaches 0.25 mass %, the action of Zr and P
to refine the grains saturates regardless of the type and content
of the other elements, and, inversely, the action of Zr and P to
refine the grains deteriorates. Therefore, the content of Zr needs
to be 0.049 mass % or less and the content of P needs to be 0.25
mass % or less in order to refined the grains effectively. If the
adding amounts of Zr and P are in the above narrow ranges, the
features of the alloy induced by the other elements are not
impaired, and further high Sn-concentration parts caused by
segregation can be distributed uniformly in the matrix by the grain
refinement, instead of being concentrated at certain areas.
Consequently, casting crack can be prevented, and a robust casting
with less porosity, shrinkage cavity, blowhole and micro-porosity
can be obtained. In addition, the workability for cold drawing or
the like, which is performed after casting, can be improved, and
thus the features of the alloy can be further improved.
[0039] Meanwhile, since Zr has a strong affinity to oxygen, Zr is
highly likely to be oxidized or sulfurated when Zr is melted in the
air or a scrap material is used as raw material. In addition, if Zr
is added excessively, the viscosity of the molten alloy increases,
therefore, zirconium oxide or sulfide can enter the molten alloy so
as to generate casting defects during casting, which leads to the
generation of blowhole or micro-porosity. Even though it can be
considered to melt the raw material and then cast the molten alloy
under vacuum or complete inert gas atmosphere to avoid the above
problems, this method cannot be used widely and raises the cost
considerably when Zr is added to copper alloy only for grain
refinement. Considering the above facts, the adding amount of Zr,
not in the form of oxide or sulfide, is preferably 0.039 mass % or
less, more preferably 0.029 mass % or less, further more preferably
0.024 mass % or less, and most preferably 0.019 mass % or less. In
addition, if the amount of Zr is in the above range, less zirconium
oxide or sulfide is generated even when the casing product is
melted in the air for recycling, and thus the robust first to
eighth copper alloys composed of fine grains can be obtained again.
Furthermore, the grains are not refined further even when the
adding amount of Zr exceeds 0.029 mass %, and the grain refinement
effect almost saturates even when the adding amount of Zr exceeds
0.039 mass %.
[0040] From the above facts, only a small amount of Zr needs to be
added industrially, therefore, the adding amount of Zr needs to be
in the range of 0.001 to 0.049 mass %, preferably 0.003 to 0.039
mass %, more preferably 0.0055 to 0.029 mass %, further more
preferably 0.0075 to 0.024 mass %, and most preferably 0.0085 to
0.019 mass %.
[0041] In addition, even though P is added with Zr to refine the
grains as described above, P also influences on the corrosion
resistance, castability or the like. Therefore, considering the
influence of the minimum amount of P on the corrosion resistance,
castability or the like and the influence of the maximum amount of
P on the ductility of the like, the adding amount of P needs to be
in the range of 0.01 to 0.25 mass %, preferably 0.02 to 0.18 mass
%, more preferably 0.025 to 0.14 mass %, further more preferably
0.03 to 0.12 mass %, and most preferably 0.035 to 0.11 mass %.
[0042] Furthermore, in order for co-added Zr and P to refine the
grains, the contents of Zr and P have to satisfy the condition (2)
as well as be in the above ranges individually. The grains are
refined when the nucleation rate of .alpha.-phase, the primary
crystal crystallized from the molten alloy, is much faster than the
growth rate of dendrite crystal. However, in order to make the
nucleation rate of .alpha.-phase much faster than the growth rate
of dendrite crystal, not only are the adding amounts of Zr and P
determined individually, but the ratio of the adding amounts of P
and Zr (f1=[P]/[Zr]) also have to be considered. The function or
interaction of Zr and P can facilitate the crystal growth of the
primary .alpha.-phase remarkably when the contents of Zr and P are
determined individually to satisfy the proper ratio of the adding
amounts in the proper ranges, and then the nucleation rate of
.alpha.-phase becomes much faster than the growth rate of the
dendrite crystal. If the contents of Zr and P are in the proper
ranges, and the proportion thereof ([P]/[Zr]) is stoichiometric, an
intermetallic compound of Zr and P (for example, ZrP or
ZrP.sub.1-x) can be generated in .alpha.-phase crystal by adding a
minute amount of Zr, for example, several tens ppm, therefore, the
nucleation rate of .alpha.-phase becomes faster when f1, the value
of [P]/[Zr], is in the range of 0.5 to 100, further faster when f1
is in the range of 0.8 to 25, still further faster when f1 is in
the range of 1.1 to 16, fastest when f1 is in the range of 1.5 to
12. That is, the ratio f1 of the adding amounts of Zr and P is an
important factor for the grain refinement, and, when f1 is in the
above range, the nucleation rate is much faster than the crystal
growth rate during the melt-solidification. Still furthermore, for
the grain refinement, the ratios of the adding amounts of Zr, P to
Sn (Zr, P to Sn and Zn when Zn is contained) (f2=([Zn]+3[Sn])/[Zr],
f3=([Zn]+3[Sn])/[P]) and f4=[Zn]+3[Sn] are considerably important,
thus need to be considered, and have to satisfy the conditions (3),
(4) and (7).
[0043] Still furthermore, as the melt-solidification proceeds and
the ratio of solid phase increases, the crystal growth occurs
frequently and part of the grains begin to combine one another,
therefore, the size of .alpha.-phase crystal increases. In this
case, if peritectic reaction occurs during the solidification of
the molten alloy, the molten alloy, not solidified yet, is reacted
with the solid .alpha.-phase, thereby generating .beta.-phase while
the amount of solid .alpha.-phase decreases. As a result,
.alpha.-phase is folded with .beta.-phase, therefore, the size of
.alpha.-phase grain decreases and the shape of .alpha.-phase grain
becomes an oval with smoothed edges. If the solid phase is fine and
oval, gas can be removed easily, and the copper alloy has a
resistance to crack accompanied by solidification shrinkage during
solidification, thereby the copper alloy is shrunk smoothly, and
various features such as strength, corrosion resistance or the like
at the room temperature are improved. It is needless to say that,
if the solid phase is fine and oval, the flowability is good, and
the copper alloy is most preferable to the semi-solid metal
solidifying method. In addition, if fine and oval solid phase and
molten alloy remain at the final stage of the solidification,
sufficient amount of the solid phase and the molten alloy can fill
every corner even in a complex-shaped mold, thereby manufacturing
excellently shaped casting products. That is, even a near net shape
can be molded. Meanwhile, in practice, that is, not in the
equilibrium state, peritectic reaction occurs in a wider
composition range than the composition range at the equilibrium
state. Herein, the equations f0 and f4 play an important role, that
is, the maximum of f0 (the minimum of f4) is related mainly with a
criterion for the grain size after the melt-solidification and the
occurrence of the peritectic reaction. The minimum of f0 (the
maximum of f4) is related mainly with the crystal size after the
melt-solidification and the boundary value that determines whether
the primary crystal is .alpha.-phase. As f0 and f4 satisfy the
above preferable range, more preferable range and most preferable
range, the amount of the primary .alpha.-phase increases, and
peritectic reaction, which occurs at a non-equilibrium reaction,
occurs actively, therefore, the grains obtained at the room
temperature becomes smaller.
[0044] The above melt-solidification phenomena depend on the
cooling rate. That is, in the case of rapid cooling that cools an
alloy at a rate of 10.sup.5.degree. C./sec or more, there is no
enough time for nucleation, therefore, the grains are likely not to
be refined. On the other hand, in the case of slow cooling that
cool an alloy at a rate of 10.sup.-3.degree. C./sec or less, the
grain growth is facilitated, thereby the grains are likely not to
be refined. In addition, since the state approaches the equilibrium
state, the composition range that generates peritectic reaction
becomes narrower. The cooling rate at the melt-solidification stage
is more preferably in the range of 10.sup.-2 to 10.sup.4.degree.
C./sec, and most preferably in the range of 10.sup.-1 to
10.sup.3.degree. C./sec. Even in the above cooling rate range, as
the cooling rate approaches the maximum, the composition range, in
which the grains are refined, is widened, therefore, the grains are
further refined.
[0045] Meanwhile, in the first to eighth copper alloys, even though
Sn alone refines the grains slightly, Sn can refine the grains
remarkably in the presence of Zr and P. Sn improves the mechanical
properties (particularly, tensile strength, proof stress, fatigue
strength and impact strength), corrosion resistance and wear
resistance. In addition, Sn divides dendrite arms and widens the
composition range of Cu or Zn, in which peritectic reaction occurs,
so as to generate more effective peritectic reaction. Furthermore,
Sn reduces the stacking fault energy of the alloy. As a result,
even though Sn granulates and refines the grains effectively, this
effect can be obtained more effectively when Sn exists with Zr and
P. In addition, .delta. and .gamma.-phases (mainly .delta.-phase),
generated by the addition of Sn, suppress the grain growth after
the melt-solidification, thereby contributing to the grain
refinement. Even though .delta.-phase (and .gamma.-phase) is an
area transformed from high Sn-concentration parts, the high
Sn-concentration parts are distributed uniformly and minutely at
the melt-solidification stage, therefore, .delta.-phase (and
.gamma.-phase) is also distributed minutely so as to suppress the
growth of .alpha.-phase crystal grains in the high temperature
region after the solidification. Furthermore, since .alpha.-phase
(and .gamma.-phase) is distributed minutely, the corrosion
resistance and wear resistance are good. Therefore, in order to
make the co-added Zr and P refine the grains effectively, it is
necessary that the contents of Zr and P be determined in
consideration of the relationship between the contents of Zr and P
and the relationship among the above contents and the content of Sn
(and Zn) and that the contents of Zr and P satisfy the conditions
(3) and (4) in addition to the condition (2). That is, in making
the co-added Zr and P refine the grains effectively, in addition to
the above relationship between the contents of Zn and P, f2
(=([Zn]+3[Sn])/[Zr]), the content ratio of Zr to Sn and Zn, and f3
(=([Zn]+3[Sn])/[P]), the content ratio of P to Sn and Zn, are also
important factors, therefore, it is necessary that f2 be in the
range of 30 to 15000 and f3 be in the range of 3 to 2500 while f1
is in the range of 0.5 to 100. The degree of the grain refinement
arising from the co-addition of Zr and P becomes larger when f1=0.8
to 25, f2=300 to 7000, and f3=60 to 1600, further larger when
f1=1.1 to 16, f2=650 to 5000, and f3=120 to 1200, and largest when
f1=1.5 to 12, f2=1000 to 3000, and f3=200 to 800.
[0046] Similar to Sn, Zn that is contained in the fifth to eighth
copper alloys generates peritectic reaction, which is a powerful
method to refine the grains during the melt-solidification of the
copper alloy, and reduces the stacking fault energy of the copper
alloy so as to improve the flowability of the molten alloy and to
facilitate the lowering of the melting point. In addition, Zn
improves the corrosion resistance and mechanical features (tensile
strength, proof stress, impact strength, wear resistance, fatigue
resistance or the like). Furthermore, Zn facilitates the grain
refinement at the melt-solidification and prevents Zr from being
oxidized. However, if a great amount of Zn is added, the primary
crystal becomes .beta.-phase at the melt-solidification, therefore,
it becomes hard to satisfy the conditions (8) to (11). Considering
the above facts, the contents of Zn needs to be in the range of
0.01 to 38 mass %, preferably in the range of 10 to 37 mass %, more
preferably in the range of 15 to 36 mass %, and most preferably in
the range of 20 to 34 mass %.
[0047] In the third, fourth, seventh and eighth copper alloys, As,
Sb and Mg are added mainly to improve the corrosion resistance.
Even though the corrosion resistance can be improved when 0.02 mass
% or more of Sb and/or As are added and 0.001 mass % or more of Mg
is added, in order to improve the corrosion resistance remarkably,
it is preferable that 0.03 mass % or more of Sb and/or As be added
and 0.002 mass % or more of Mg be added. Furthermore, it is more
preferable that 0.005 mass % or more of Mg be added. On the other
hand, even when the adding amount of Sb or As exceeds 0.2 mass %,
the corresponding effect cannot be obtained, and the ductility
deteriorates inversely. In addition, the copper alloy becomes
toxic. Considering the above facts, the adding amount of Sb or As
needs to be 0.2 mass % or less and preferably 0.12 mass % or less.
Meanwhile, even though it is common to use a scrap material
(scrapped heat pipe) as a raw material for the copper alloy, and
such scrap material contains S-component (sulfur-component), if the
S-component is contained in the molten alloy, Zr, a grain-refining
element, is likely to be sulfurated so as not to contribute to the
grain refinement and further to impair the flowability, therefore,
casting defects such as blowhole, crack or the like are highly
likely to occur. Not only does Mg improve the corrosion resistance,
but Mg also improves the flowability of the molten alloy when a
scrap material containing the S-component is used for casting as a
raw material of an alloy. In addition, Mg can remove the
S-component in the form of MgS, which is less harmful than the
S-component and not harmful to the corrosion resistance even when
MgS remains in the alloy, and prevent the deterioration of the
corrosion resistance caused by the S-component contained in the raw
material. Furthermore, if the raw material contains the
S-component, the S-component is highly likely to exist in the grain
boundary so as to cause the intergranular corrosion. However, the
intergranular corrosion can be effectively prevented by adding Mg.
Still furthermore, even though it is likely that the concentration
of S in the molten alloy becomes high and thus Zr is consumed by S,
if 0.001 mass % or more of Mg is contained in the molten alloy
before the charging of Zr, the S-component in the molten alloy is
removed or fixed in the form of MgS, thereby preventing such
problem. However, if Mg is added excessively, for example, more
than 0.2 mass %, Mg is oxidized like Zr, and the viscosity of the
molten alloy increases, thereby generating casting defects caused
by the inclusion of the oxide or the like. Therefore, considering
the above facts, the adding amount of Mg needs to be in the range
of 0.001 to 0.2 mass %, preferably 0.002 to 0.15 mass %, and more
preferably 0.005 to 0.1 mass %.
[0048] In the second, fourth, sixth and eighth copper alloys, Al,
Mn, Si and Co are added mainly to improve the strength. Al, Mn and
Sn induce the improvement of the flowability of the molten alloy,
deoxidation, desulfuration, the improvement of the erosion
resistance and the improvement of wear resistance under a strong
current as well as the improvement of the strength. Particularly,
Al and Si form robust Al--Sn and Si--Sn corrosion resistant
coatings individually on the surface of a casting so as to improve
the erosion resistance. In addition, Mn also forms the corrosion
resistant coating between Sn and Mn. Furthermore, even though not
as much as Mg, Al and Mn also remove the S-component in the molten
alloy. Still furthermore, when a large amount of oxygen exists in
the molten alloy, Zr is oxidized so as not to refine the grains,
and, in this case, Al and Mn prevent Zr from being oxidized. Si
deoxidizes and further reduces the stacking fault energy of the
alloy if contained with Zr, P, Cu and Zn so as to refine the grains
remarkably. Furthermore, Si improves the flowability of the molten
alloy, prevents the molten alloy from being oxidized, and reduces
the melting point, thereby improving the corrosion resistance,
particularly, dezincification corrosion resistance and stress
corrosion cracking resistance. Still furthermore, Si contributes to
the improvement of the machinability and mechanical strength such
as tensile strength, proof stress, impact strength, fatigue
strength or the like. The above actions induce synergy effect on
the grain refinement of the casting. Still furthermore, if added
with Mn and Si, Si forms a Mn--Si intermetallic compound so as to
improve the wear resistance. Co suppresses the coarsening of the
grains induced under high-temperature heating condition and
improves the strength of the copper alloy. That is, the addition of
Co preferably suppresses the grain growth induced when the Sn
containing alloy is heated at the high-temperature, and then the
metallic composition can be held minutely, and the fatigue
resistance of the copper alloy after the high-temperature heating
is improved. Considering the above facts, the contents of Mn, Al,
Si and Co need to be in the above ranges.
[0049] In order to secure sufficient corrosion resistance, wear
resistance, strength or the like, the first to eighth copper alloys
need to form the above alloy compositions and to satisfy the
condition (5). That is, the first to eighth copper alloys need to
form phase structures (metal structures), in which the total
content of .alpha. and .delta.-phases (and/or .gamma.-phase) is 90%
or more (preferably 98% or more, and more preferably 99% or more)
by area ratio. However, if the content of .delta.-phase (and/or
.gamma.-phase) is excessive, the selective corrosion of the phase
is generated so as to impair the corrosion resistance. In addition,
even though .delta. and .gamma.-phases improve the wear resistance
and erosion resistance, .delta. and .gamma.-phases also impair the
ductility. Therefore, in order to maintain the strength, wear
resistance and ductility in balance without causing the
deterioration of the corrosion resistance in the above phase
structure, it is preferable that the content of .delta. and
.gamma.-phases be controlled to be in the range of 0 to 20% (more
preferably 0 to 10%, and further preferably 0 to 5%) by area ratio.
If the grains are refined by adding Zr and P together, not only are
.delta. and .gamma.-phases divided and refined, but .delta. and
.gamma.-phases can also be distributed uniformly in the matrix,
thereby improving various mechanical features and wear resistance
(slidability) considerably.
[0050] In order for the first to eighth copper alloys to form the
above phase structure and to satisfy the condition (6), it is
preferable that the content of Sn be adjusted in consideration of
the relationship between `Sn` and `Cu and the other additives`.
That is, in order to refine the grains more effectively, not only
do the contents of Sn or the like satisfy the conditions (2) to
(4), but it is also preferable that the contents of Sn or the like
be determined to satisfy the condition (1) (the conditions (1) and
(7) in the cases of the fifth to eighth copper alloys) and the
maximum of
f0(=[Cu]-0.5[Sn]-3[P]-0.5([As]+[Sb])+[Mg]+[Mn]-1.8[Al]-3.5[Si]) or
the minimum of f4(=[Zn]+3[Sn]) be set as described above in the
relationship of the contents of Cu, a main element, or the like in
order to secure more excellent strength, corrosion resistance
(erosioncorrosion resistance) and wear resistance. Meanwhile,
considering the elongation, corrosion resistance and castability
influenced by .delta. and .gamma.-phases, it is preferable to
control and set the minimum of f0 or the maximum of f4 as described
above. In order to secure the above features, the concentration of
Sn varies with the concentration of Cu.
[0051] In the first to eighth copper alloys, the grains are refined
by adding Zr and P. In addition, high-quality casting products can
be obtained and casting products by continuous casting such as
horizontal continuous casting, upward (upcast) or the like can be
provided and used practically by satisfying the condition (6), that
is, by making the mean grain size in the macrostructure 300 .mu.m
or less (preferably 200 .mu.m or less, and more preferably 100
.mu.m or less; in addition, 60 .mu.m or less in the microstructure)
at the melt-solidification. When the grains are not refined, a
plurality of heat treatments is required to eliminate dendrite
structure peculiar to casting products and the segregation of Sn,
and to divide and granulate .delta. and .gamma.-phases, and the
surface state of casting products become bad since the grains are
coarsened. However, when the grains are refined as described above,
the segregations are small and short, therefore, heat treatment is
not required, and the surface state is good. In addition, since
.delta. and .gamma.-phases exist in the grain boundary even when 6
and y-phases are precipitated, the length of .delta. and
.gamma.-phases become short as the grains become finer and are
distributed uniformly, therefore, specific treatment is not
required to divide .delta. and .gamma.-phases, or heat treatment is
carried out to the minimum, if necessary. As described above, the
number of processes required to manufacture a casting product is
reduced considerably, therefore, the manufacturing cost can be
decreased as much as possible. Meanwhile, if the condition (6) is
satisfied, the following problems are not caused, therefore, the
copper alloy exhibit excellent features. That is, when the size of
each .delta. phase containing a large amount of Sn, a low-melting
point metal, varies, and .delta. phase is distributed unevenly, the
difference of the strength of .delta.-phase and .alpha.-phase in
the matrix causes crack easily, and the ductility at the room
temperature is impaired.
[0052] In addition, since the cold workability and hot workability
are improved as .delta. and .gamma.-phases are distributed
uniformly and the length of .delta. and .gamma.-phase or grain size
becomes smaller, the first to eighth copper alloys can be used
preferably for usages requiring caulking process (for example,
there can be a case where caulking process is required when a hose
nipple is installed).
[0053] Meanwhile, even though it is expected that the strength,
corrosion resistance or the like is improved considerably as the
content of Sn increases, for example, a large amount of Sn,
exceeding 5 or 8 mass %, is added, on the other hand, Sn is
segregated considerably, and thus crack, shrinkage cavity, blowhole
or micro-porosity is highly likely to occur at the
melt-solidification. However, when the grains are refined at the
melt-solidification, such problems do not occur, and the further
improvement of the strength, fatigue strength, seawater resistance,
erosioncorrosion resistance or the like, achieved by adding a large
amount of Sn, can be sought. In addition, Zr and P are added
together only to refine the grains, not to impair the inherent
features of the copper alloy. Furthermore, the identical or better
features of the copper alloy having the same composition except
that no Zr and P are contained as the grain-refining element are
secured by the grain refinement achieved by the co-addition of Zr
and P. In order to make the mean grain size small at the
melt-solidification, it is required to determine the content of Zr
or the like to satisfy the conditions (2) to (5), and it is
preferable that the contents of Sn or the like be determined to
satisfy the conditions (1) to (4) for the first to eighth copper
alloys and further to satisfy the condition (7) for the fifth to
eighth copper alloys.
[0054] In addition, for the first to eighth copper alloys, there
can be cases where scrap material is used as raw material, and when
such scrap material is used, it is inevitable and permitted
practically to contain impurities. However, when scrap material is
a nickel plating material or the like, if Fe and/or Ni are
contained as inevitable impurities, the content of Fe and/or Ni
need to be controlled. That is, it is because Zr and P, which are
useful for the grain refinement, are consumed by Fe and/or Ni, if
the content of the impurities are large, thereby impeding the grain
refinement. As a result, when either Fe or Ni is contained, it is
preferable to control the content of the impurity to be 0.25 mass %
or less (preferably 0.1 mass % or less, and most preferably 0.06
mass % or less). Furthermore, when both Fe and Ni are contained, it
is preferable to control the content of Fe and Ni to be 0.3 mass %
or less (more preferably 0.13 mass % or less, and most preferably
0.08 mass % or less).
[0055] In the preferred embodiments, the first to eighth copper
alloys are provided in the form of, for example, casting product
obtained by a casting process or plastic-worked product, which is
the casting product that is further plastic-worked one or more
times.
[0056] The casting product is provided in the form of, for example,
wire, rod or hollow bar cast by horizontal continuous casting
method, upward method or upcast method; or is provided as near net
shaped product. In addition, the casting product is also provided
in the form of casting, semi-solid metal casting, semi-solid metal
molding, molten alloy forging or die casting molding. In this case,
it is preferable that the molten alloy satisfy the conditions (12)
and (13). If the solid phase is granulated in the semi-solid metal
state, the semi-solid metal castability of the molten alloy becomes
excellent, therefore, it is possible to carry out the semi-solid
metal casting satisfactorily. Furthermore, even though the
flowability of the molten liquid containing the solid phase at the
final stage of solidification depends mainly on the shape of the
solid phase, the viscosity of the liquid phase or the composition
of the liquid phase, the moldability by casting (whether a robust
casting can be cast even when high-precision or complex-shaped
casting is required) is influenced considerably by the former
factor (the shape of the solid phase). That is, if the solid phase
begins to form dendrite network at the semi-solid metal state, the
molten alloy containing the solid phase is hard to fill every
corner of the mold, therefore, the moldability by casting
deteriorates, and high-precision or complex-shaped casting products
are difficult to obtain. Meanwhile, as the solid phase is
granulated in the semi-solid metal state, and the shape of the
solid phase becomes substantially spherical (circular in two
dimension), the castability including the semi-solid metal
castability is improved as much as the grain size becomes smaller,
and thus a robust and high-precision or complex-shaped casting
product can be obtained (it is needless to say that a high-quality
semi-solid metal casting product can be obtained). Therefore, the
semi-solid metal castability can be evaluated by checking the shape
of the solid phase at the semi-solid metal state, and the other
castabilities (complex-shaped castability, precision castability
and melt-solidification forgeability) can be verified by the degree
of the semi-solid metal castability. In general, when the dendrite
network is divided in the crystal structure and the two-dimension
shape of the solid phase is circular, substantially circular, oval,
cross-like or polygonal at the semi-solid metal state, in which the
solid phase occupies 30 to 80%, the semi-solid metal castability is
good. In addition, particularly when either the mean grain size of
the solid phase is 150 .mu.m or less (preferably 100 .mu.m or less,
and more preferably 50 .mu.m or less) or the mean maximum length of
the solid phase is 200 .mu.m or less (preferably 150 .mu.m or less,
and more preferably 100 .mu.m or less) at the semi-solid metal
state, in which the solid phase occupies 60%, the semi-solid metal
castability is excellent.
[0057] In addition, a plastic-worked product is provided in the
form of hot worked product (hot drawing worked product, hot forging
worked product or hot rolling worked product) or cold worked
product (cold rolling worked product, cold drawing worked product),
and, in any case, proper heat treatment, cutting process or the
like is performed additionally according to the necessity.
[0058] Specifically, the first to eighth copper alloys are provided
in the form of the following casting product or plastic-worked
product, which is the casting product plastic-worked one or more
times. For example, the casting product includes gear, worm gear,
bearing, bush, impeller, common mechanical parts, metal fitting for
water contact, joint or the like. In addition, the plastic-worked
product includes electronicelectric device spring, switch, lead
frame, connector, bellows, fuse grip, bush, relay, gear, cam,
joint, flange, bearing, machine screw, bolt, nut, metal eyelet,
heat exchanger tube sheet, heat exchanger, metallic mesh, sea net,
breeding net, fish net, header material, washer, seawater condenser
tube, ship parts shaft, seawater intake of a ship, metal fitting
for water contact or the like.
[0059] Furthermore, in manufacturing the first to eighth copper
alloys, the invention proposes a method of casting a copper alloy
casting product having excellent strength, wear resistance and
corrosion resistance, in which Zr is not added in the form of oxide
and/or sulfide during casting by adding Zr (contained to further
refine the grains and to make the grain refinement more stable) in
the form of a copper alloy containing Zr right before pouring or at
the final stage of raw material melting. It is preferable that the
copper alloy containing Zr further contain one or more elements
selected from P, Mg, Al, Sn, Mn and B as additives to a base
material, that is, Cu--Zr alloy, Cu--Zn--Zr alloy or the alloy of
Cu--Zr alloy and Cu--Zn--Zr alloy.
[0060] That is, in the casting process of the first to eighth
copper alloys or the component (materials to be plastic-worked),
the loss of Zr during the addition of Zr is reduced as much as
possible by adding Zr in the form of granular, thin plate-like,
rod-like or wire-like master alloy (copper alloy) right before
pouring, thereby preventing Zr from being added in the form of
oxide and/or sulfide during casting, which causes the lack of Zr
required to refine the grains. In addition, when Zr is added right
before pouring as described above, since the melting point of Zr is
800 to 1000.degree. C. higher than that of the copper alloy, it is
preferable that Zr be used in the form of a low-melting point
alloy, which is a granular (grain diameter: about 2 to 50 mm), thin
plate-like (thickness: about 1 to 10 mm), rod (diameter: about 2 to
50 mm) or wire-like master alloy having the melting point close to
that of the copper alloy and containing a large amount of necessary
elements (for example, Cu--Zr alloy or Cu--Zn--Zr alloy containing
0.5 to 65 mass % of Zr; or an alloy further containing one or more
elements selected from P, Mg, Al, Sn, Mn and B (the content of each
element: 0.1 to 5 mass %) as additives to the base material, that
is, the alloy of Cu--Zr alloy and Cu--Zn--Zr alloy) Particularly,
in order to facilitate the melting by lowering the melting point
and to prevent the loss of Zr due to the oxidation of Zr, it is
preferable to use Zr in the form of an alloy that adopts Cu--Zn--Zr
alloy containing 0.5 to 35 mass % of Zr and 15 to 50 mass % of Zn
(preferably Cu--Zn--Zr alloy containing 1 to 15 mass % of Zr and 25
to 45 mass % of Zn) as the base. While depending on the proportion
of Zr to P, which is added together with Zr, Zr impairs the
electricthermal conductive properties, that is, the inherent
properties of the copper alloy. However, if the amount of Zr, not
in the form of oxide and sulfide, is 0.039 mass % or less,
particularly 0.019 mass % or less, the electricthermal conductivity
is seldom impaired by the addition of Zr, and further, the
electricthermal conductivity is less impaired as compared with when
Zr is not added, if impaired.
[0061] In addition, in order to obtain the first to eighth copper
alloys satisfying the condition (6), it is desirable to adjust
properly the casing conditions, particularly, pouring temperature
and cooling rate. That is, it is preferable that the pouring
temperature be determined in the range of 20 to 250.degree. C.
above the liquidus line temperature of the copper alloy (more
preferably 25 to 150.degree. C. above the liquidus line
temperature). That is, it is preferable that (the liquidus line
temperature+20.degree. C.).ltoreq.the pouring
temperature.ltoreq.(the liquidus line temperature+250.degree. C.)
and more preferable that (the liquidus line temperature+25.degree.
C.).ltoreq.the pouring temperature.ltoreq.(the liquidus line
temperature+150.degree. C.). Generally, the pouring temperature is
1200.degree. C. or less, preferably 1150.degree. C. or less, and
more preferably 1100.degree. C. or less. Even though the minimum
pouring temperature is not limited as long as the molten alloy can
fill every corner of the molder, as the pouring temperature is
lowered, the grains are refined further. Meanwhile, it has to be
understood that the above temperature conditions vary with the
chemical composition of the alloy.
[0062] Since the grains are refined during the melt-solidification,
the Sn-containing copper alloy of the invention can endure
shrinkage during solidification, thereby inducing less casting
crack. In addition, since air causing holes or porosity in the
process of solidification can be removed easily to the outside, a
robust casting product with no casting defect (since casting defect
such as porosity or the like does not exist, dendrite network is
not formed, the surface is smooth, and the shrinkage cavity is as
thin as possible) can be obtained. Therefore, the invention can
provide a casting product extremely rich in practicality or a
plastic-worked product, which is the casting product plastic-worked
one or more times.
[0063] In addition, since the crystals crystallized in the process
of solidification are not dendrite, a typical shape of a casting
structure, but broken arm-shaped, preferably circular, oval,
polygonal or cross-like, the flowability of the molten alloy is
improved, and thus the molten alloy can fill every corner of a
molder having thin wall and complex shape.
[0064] Since the copper alloy of the invention considerably
improves the strength, wear resistance (slidability), corrosion
resistance, castability by refining the grains and distributing
phases other than .alpha.-phase (.delta. and .gamma.-phases
generated by Sn) uniformly, the copper alloy can be used
practically for a casting product demanding the above features (for
example, gear, worm gear, bearing, bush, impeller, common
mechanical parts, metal fitting for water contact, joint or the
like) or a plastic-worked product that requires coldhot process
(for example, electricelectronic device spring, switch, lead frame,
connector, bellow, fuse grip, bush, relay, gear, cam, joint,
flange, bearing, machine screw, bolt, nut, metal eyelet, heat
exchanger pipe, heat exchanger, metallic mesh, sea net, breeding
net, fish net, header material, washer, seawater condenser tube,
ship parts shaft, seawater intake of a ship, metal fitting for
water contact or the like)
[0065] Even though the Cu--Sn alloy containing 8 mass % of Sn is
used for a high class connector (for example, the connector of a
cellular phone or the like) and thus it is highly demanded to
strengthen the alloy by increasing the content of Sn, the
strengthening causes a problem in the castability and thus cannot
be realized. However, since the copper alloy of the invention can
improve the castability of the alloy by refining the grains, the
copper alloy can realize the above demand sufficiently and can be
provided as a high-class connector. The Cu--Zn--Sn alloy containing
Zn can do the same thing. Therefore, the invention can provide the
Cu--Sn alloy or Cu--Zn--Sn alloy that satisfies inconsistent
demands, that is, the improvement of strength and castability,
thereby widening the usage of the Sn-containing copper alloy.
[0066] Furthermore, since the method of the invention can refine
the grains by adding Zr and P together without inducing the problem
caused by adding Zr in the form of oxide and sulfide, the copper
alloy can be cast efficiently and preferably.
BRIEF DESCRIPTION OF THE DRAWINGS
[0067] FIG. 1 includes photographs of etched surface
(cross-section) of a copper alloy for embodiment No. 5, in which
FIG. 1(A) shows a macrostructure, and FIG. 1(B) shows a
microstructure.
[0068] FIG. 2 includes photographs of etched surface
(cross-section) of a copper alloy for comparative example No. 107,
in which FIG. 2(A) shows a macrostructure, and FIG. 2(B) shows a
microstructure.
[0069] FIG. 3 includes photographs of etched surface
(cross-section) of a copper alloy for embodiment No. 18, in which
FIG. 3(A) shows a macrostructure, and FIG. 3(B) shows a
microstructure.
[0070] FIG. 4 includes photographs of etched surface
(cross-section) of a copper alloy for comparative example No. 112,
in which FIG. 4(A) shows a macrostructure, and FIG. 4(B) shows a
microstructure.
[0071] FIG. 5 includes X-ray micro-analyzer photographs of etched
surface (cross-section) of a copper alloy for embodiment No. 18, in
which FIG. 5(A) shows a composition image, and FIG. 5(B) shows a
distribution of Sn.
[0072] FIG. 6 includes X-ray micro-analyzer photographs of etched
surface (cross-section) of a copper alloy for comparative example
No. 112, in which FIG. 6(A) shows a composition image, and FIG.
6(B) shows a distribution of Sn.
[0073] FIG. 7 includes cross-sectional views showing a result of
Tatur test, in which FIG. 7(A) shows `good`-ranked copper alloy,
FIG. 7(B) shows `fair`-ranked copper alloy, and FIG. 7(C) shows
`bad`-ranked copper alloy.
BEST MODE FOR CARRYING OUT THE INVENTION
[0074] As embodiments, copper alloy materials having the
compositions listed in Table 1 are melted in an electric furnace,
and then the molten alloy is poured into an iron-made molder
preheated up to 200.degree. C. so as to manufacture cylindrical
(diameter: 40 mm, length: 280 mm) ingots (hereinafter referred to
as `copper alloys for embodiment`) Nos. 1 to 33. When the ingots
for the first to fourth copper alloys are manufactured, Zr is added
to the molten alloy in the form of granular Cu--Zr alloy (cubic
body with several mm long sides) right before pouring. As a result,
Zr is prevented from being added in the form of oxide and sulfide.
Likewise, when the fifth to eighth copper alloys are manufactured,
Zr is added to the molten alloy in the form of granular Cu--Zn--Zr
alloy (cubic body with several mm long sides) right before pouring.
Furthermore, the pouring temperatures are set to be 100.degree. C.
above the liquidus line temperatures of the copper alloys.
[0075] In addition, as comparative examples, copper alloy materials
having the compositions listed in Table 2 are melted in an electric
furnace, and then the molten alloy is poured into an iron-made
molder preheated up to 200.degree. C. under the same conditions as
those of the embodiments so as to cast cylindrical (diameter: 40
mm, length: 280 mm) ingots (hereinafter referred to as `copper
alloys for comparative example`) Nos. 101 to 116.
[0076] No. 10 Specimen defined in JIS Z 2201 is taken from the
copper alloys for embodiment and the copper alloys for comparative
example, and then tensile strength test is performed on the
specimens by AMSLER universal testing machine so as to measure the
tensile strength (N/mm.sup.2), 0.2% proof stress (N/mm.sup.2) and
elongation (%). The result is illustrated in Tables 3 and 4.
[0077] In order to check the corrosion resistance of the copper
alloys for embodiment and the copper alloys for comparative
examples, the following erosioncorrosion test and dezincification
corrosion test defined in `ISO 6509` are performed.
[0078] That is, for the erosioncorrosion test, 3% saline solution
(30.degree. C.) is sprayed to the specimens taken from the copper
alloys for embodiment and the copper alloys for comparative example
through a 1.9 mm diameter nozzle at a speed of 11 m/sec in a
direction perpendicular to the axis of the species for 96 hours,
and then the mass loss (mg/cm.sup.2) is measured. The mass loss is
the difference of mass per one square centimeter (mg/cm.sup.2)
between the mass of the original specimen and the mass of the
specimen sprayed with the 3% saline solution for 96 hours. The
result of the erosioncorrosion test is illustrated in Tables 3 and
4.
[0079] For the dezincification corrosion test of `ISO 6509`, the
specimens taken from the copper alloys for embodiment and the
copper alloys for comparative example are molded with phenol resin
so as to make the exposed surfaces of the specimens face
perpendicular to the extension direction, and then the surfaces are
polished with Emery paper up to No. 1200. After that, the surfaces
are ultrasonic-cleaned in pure water and then dried. The obtained
corrosion test specimens are soaked in an aqueous solution of 1.0%
Cupric Chloride Dihydrate (CuCl.sub.2.2H.sub.2O) for 24 hours at
the temperature of 75.degree. C. After that, the specimens are
removed from the aqueous solution, and then the maximum depth of
dezincification corrosion, that is, the maximum dezincification
corrosion depth (.mu.m), is measured. The result is illustrated in
Tables 3 and 4.
[0080] From the above test results, it is verified that the
embodiments are more excellent in both of the mechanical properties
(strength, elongation or the like) and the corrosion resistance
than the comparative examples. In addition, even though it is
possible to consider that the elongation is reduced by the grain
refinement, the result of the tensile test shows that the
elongation of the Sn-containing copper alloy of the invention is
not reduced, inversely, improved.
[0081] In addition, in order to evaluate the cold workability of
the copper alloys for embodiment and the copper alloys for
comparative example, the following cold compression test is
performed.
[0082] That is, cylindrical specimens with a diameter of 5 mm and a
height of 7.5 mm are cut by a lathe from the copper alloys for
embodiment and the copper alloys for comparative example, and then
compressed by AMSLER universal test machine so as to evaluate the
cold workability on the basis of the relationship between the
existence of crack and the compression rate (processing rate). The
result is illustrated in Tables 3 and 4. In the tables, specimens
having crack at the compression rate of 50% are denoted by `x` as a
meaning of bad cold workability; specimens having no crack at the
compression rate of 65% are denoted by `O` as a meaning of good
cold workability; and specimens having no crack at the compression
rate of 50%, however, having crack at the compression rate of 65%
are denoted by `.DELTA.` as a meaning of fair cold workability.
[0083] Furthermore, in order to evaluate the hot workability of the
copper alloys for embodiment and the copper alloys for comparative
example, the following high-temperature compression test is
performed.
[0084] That is, cylindrical specimens with a diameter of 15 mm a
height of 25 mm are taken from the copper alloys for embodiment and
the copper alloys for comparative example by a lathe and then held
at the temperature of 700.degree. C. for 30 minutes. After that,
the specimens are hot-compressed while the processing rate is
varied so as to evaluate the hot workability on the basis of the
relationship between the processing rate and the crack. The result
is illustrated in Tables 3 and 4. In the tables, specimens having
no crack at the processing rate of 65% are denoted by `O` as a
meaning of good hot workability; specimens having a small number of
little cracks at the processing rate of 65%, however, having no
crack at the processing rate of 55% are denoted by `.DELTA.` as a
meaning of fair hot workability; and specimens having crack at the
processing rate of 55% are denoted by `x` as a meaning of bad hot
workability.
[0085] From the above test results, it is verified that the copper
alloys for embodiment are excellent in both of the cold workability
and the hot workability.
[0086] Still furthermore, for the copper alloys for embodiment and
the copper alloys for comparative example, the phase structure at
the room temperature after melt-solidification is checked, and the
area ratio (%) of .alpha., .gamma. and .delta.-phases is measured
by image analysis. That is, the structures of the copper alloys,
200 times magnified by an optical microscope, are expressed in the
binary system with an image processing software `WinROOF` so as to
measure the area ratio of each phase. The area ratio is measured in
three dimensional, and the average value of the area ratio is
regarded as the phase ratio of each phase. The result is
illustrated in Table 1 and 2. All copper alloys for embodiment
satisfy the condition (5). In addition, Tables 3 and 4 illustrate
the primary crystals, crystallized during melt-solidification in
casting process, for the copper alloys for embodiment and the
copper alloys for comparative example. Since having .alpha.-phase
primary crystal, all copper alloys for embodiment satisfy the
condition (8).
[0087] Still furthermore, for the copper alloys for embodiment and
the copper alloys for comparative example, the mean grain size
(.mu.m) during melt-solidification is measured. That is, a casting
product is divided, and the cross-section is etched by nitric acid.
After that, the mean grain size of the microstructure displayed on
the etched surface is measured. The measurement is based on the
comparative method for estimating average grain size of wrought
copper and copper alloys of JIS H0501, herein, grains having the
diameter of more than 0.5 mm are observed by eyes, and grains
having the diameter of 0.5 mm or less is 7.5 times magnified for
observation after the divided surface is etched by nitric acid. In
addition, grains having the diameter of less than about 0.1 mm are
etched by a mixed liquid of hydrogen peroxide and ammonia water and
then 75 times magnified by an optical microscope for observation.
The result is illustrated in Tables 3 and 4, and all copper alloys
for embodiment satisfy the condition (6). Furthermore, it is
verified that the copper alloys for embodiment satisfy the
conditions (10) to (11). FIGS. 1 to 6 show an example.
[0088] FIG. 1 includes a photograph of the macrostructure (FIG.
1(A)) and a photograph of the microstructure (FIG. 1(B)) of the
copper alloy for embodiment No. 5 that contains no Zn. FIG. 2
includes a photograph of the macrostructure (FIG. 2(A)) and a
photograph of the microstructure (FIG. 2(B)) of the copper alloy
for comparative example No. 107, Cu--Sn alloy containing no Zn,
like the copper alloy No. 5, and the same content of Sn as that of
the copper alloy No. 5. FIG. 3 includes a photograph of the
macrostructure (FIG. 3(A)) and a photograph of the microstructure
(FIG. 3(B) of the copper alloy for embodiment No. 18 that contains
Zn. FIG. 4 includes a photograph of the macrostructure (FIG. 4(A))
and a photograph of the microstructure (FIG. 4(B)) of the copper
alloy for comparative example No. 112, Cu--Zn--Sn alloy that
contains Zn and the same content of Sn as that of the copper alloy
No. 18. From FIGS. 1 to 4, it is evident that the copper alloys for
embodiment Nos. 5 and 18 satisfy the conditions (10) and (11);
however, the copper alloys for comparative example Nos. 107 and 112
do not satisfy the conditions (10) and (11). Furthermore, FIG. 5
includes X-ray micro-analyzer photographs of the casting products
of Embodiment No. 18, in which FIG. 5(A) shows the composition and
FIG. 5(B) shows the distribution of Sn. Still furthermore, FIG. 6
includes X-ray micro-analyzer photographs of the casting products
of Comparative Example No. 112, in which FIG. 6(A) shows the
composition and FIG. 6(B) shows the distribution of Sn. From FIG.
5, it is evident that, since the high Sn-concentration parts (white
parts in FIG. 5(B)) of similar small sizes are distributed
uniformly, the casting product of Embodiment No. 18 satisfies the
condition (11). On the other hand, in the copper alloy for
Comparative example No. 112, as shown in FIG. 6, the high
Sn-concentration parts (white parts in FIG. 6(B)) have irregular
sizes and are distributed non-uniformly, thereby not satisfying the
condition (11).
[0089] From the above facts, it can be understood that the grains
can be refined effectively and the high Sn-concentration part can
be refined and distributed by adding a proper amount of Zr and P
under the above conditions. In addition, comparing the results of
the corrosion resistance test or the like and the result of the
Tatur test, described below, it is evident that the copper alloys
for Embodiment Nos. 5 and 18 have better corrosion resistance,
castability or the like than the copper alloys for comparative
example Nos. 107 and 112. Therefore, it can be understood that
satisfying the conditions (10) and (11) is very important in
improving the corrosion resistance, castability or the like.
[0090] Still furthermore, even though it is considered that the
castability is improved by satisfying the condition (6), that is,
by refining the grains, in order to verify this fact, the following
Tatur shrinkage test and semi-solid metal castability test are
performed.
[0091] That is, Tatur shrinkage test is performed on the molten
alloys (the molten alloys of the copper alloy materials having the
compositions listed in Table 1 or 2) used in casting the copper
alloys for embodiment and the copper alloys for comparative
example, and then the castability is evaluated by checking the
shape of internal shrunk portion and the existence of casting
defect such as porosity, hole, shrinkage cavity or the like in the
vicinity of the internal shrunk portion. The castability is
evaluated to be `good` for copper alloys having a smooth internal
shrunk portion and no defect such as porosity or the like in the
finally solidified portion as shown in FIG. 7(A), `bad` for copper
alloys having a non-smooth, that is, remarkably uneven, internal
shrunk portion and defect such as porosity or the like in the
finally solidified portion as shown in FIG. 7(C), and `fair` for
copper alloys evaluated neither `good` nor `bad` as shown in FIG.
7(B). The result is illustrated in Tables 5 to 8. In the tables,
`good` is denoted by `O`, `fair` is denoted by `.DELTA.`, and `bad`
is denoted by `x`. Meanwhile, it is also verified that the grain
size of the macrostructure of the casting products obtained for the
Tatur test substantially corresponds to the measuring result of the
grain size of the copper alloys for embodiment and the copper
alloys for comparative examples as described above.
[0092] In the semi-solid metal castability test, raw material used
in casting the copper alloys for embodiment and the copper alloys
for comparative example is charged into a crucible; heated up to a
temperature, at which the raw material forms a semi-solid metal
(solid phase ratio: about 60%); held at the temperature for 5
minutes; and then cooled rapidly (water cooling). After that, the
shape of the solid phase at the semi-solid metal state is
investigated so as to evaluate the semi-solid metal castability.
The result is illustrated in Tables 3 and 4, and it is verified
that the copper alloys for embodiment have excellent semi-solid
metal castability. Meanwhile, in the tables, copper alloys having
the mean grain size of the solid phase of 150 .mu.m or less or the
mean maximum grain length of 300 .mu.m or less are denoted by `O`
as a meaning of good semi-solid metal castability; copper alloys
having the grain size of the solid phase not satisfying the above
condition, but, having no dendrite network therein are denoted by
`.DELTA.` as a meaning of industrially satisfactory semi-solid
metal castability; and copper alloys having dendrite network
therein are denoted by `x` as a meaning of bad semi-solid metal
castability.
[0093] It can be understood from the above test results that the
copper alloys for embodiment have better castability and semi-solid
metal castability than the copper alloys for comparative
example.
[0094] Meanwhile, a new casting product (hereinafter referred to as
`recycled casting product`) is cast by using the copper alloy
casting product (including the specimen used in the tensile
strength test) No. 18 (hereinafter referred to as `product
casting`) obtained in the embodiment as raw material. That is, the
product casting (the copper alloy casting No. 18) is re-melted at
the temperature of 1030.degree. C. in a state that the molten alloy
is coated with charcoal and held for 5 minutes, and then Cu--Zn--Zr
alloy containing 3 mass % of Zr is further added to replenish the
oxidation loss of Zr in melting, which is expected to be 0.0015
mass %. After that, the product casting is poured into a molder. As
a result, the obtained recycled casting product has the content of
Zr, almost equal to that of the product casting No. 18, raw
material, (0.0096 mass %) and the mean grain size, almost equal to
that of the product casting No. 18, that is, 35 .mu.m. From the
above fact, it is verified that the copper alloy casting product of
the invention can effectively use surplus part or unnecessary part
such as runner or the like generated in casting as recycling
material without impairing the grain refinement. Therefore, the
surplus part or unnecessary part such as molten alloy passage can
be used as replenishing material, which is charged during
continuous operation, and perform the continuous operation
effectively and economically.
TABLE-US-00001 TABLE 1 Area Copper ratio alloy Alloy composition
(mass %) (%) No. Cu Zn Zr P Sn f0 f1 F2 f3 f4 .alpha. + .gamma. +
.delta. Embodiment 1 95.7 0.033 0.05 4.2 93.5 1.5 382 252 12.6 100
2 93.8 0.028 0.07 6.1 90.5 2.5 654 261 18.3 100 3 92 0.023 0.06 7.9
87.9 2.6 1030 395 23.7 100 4 89.8 0.0084 0.06 10.1 84.6 7.1 3607
505 30.3 100 5 89.8 0.014 0.06 10.1 84.6 4.3 2164 505 30.3 100 6
89.8 0.022 0.06 10.1 84.6 2.7 1377 505 30.3 100 7 89.7 0.028 0.07
10.2 84.4 2.5 1093 437 30.6 100 8 89.8 0.035 0.06 10.1 84.6 1.7 866
505 30.3 100 9 88.1 0.02 0.06 11.8 82.0 3.0 1770 590 35.4 100 10
84.7 0.019 0.12 15.1 76.8 6.3 2384 378 45.3 100 11 89.7 0.019 0.07
10.1 84.5 3.7 1595 433 30.3 100 12 89.7 0.018 0.06 10.1 84.4 3.3
1683 505 30.3 100 13 89.8 0.021 0.07 10.1 84.5 3.3 1443 433 30.3
100 14 78 21.60 0.019 0.06 0.32 77.7 3.2 1187 376 22.6 100 15 75.5
24.38 0.018 0.05 0.05 75.3 2.8 1363 491 24.5 100 16 72.8 25.95
0.0029 0.05 1.2 72.1 17.2 10189 591 29.5 100 17 73.2 25.55 0.0068
0.04 1.2 72.5 5.9 4287 729 29.2 100 18 73.4 25.34 0.0095 0.05 1.2
72.7 5.3 3046 579 28.9 100 19 73.1 25.62 0.016 0.06 1.2 72.3 3.8
1827 487 29.2 100 20 73.4 25.32 0.035 0.05 1.2 72.7 1.4 826 578
28.9 100 21 73 25.76 0.021 0.015 1.2 72.4 0.7 1398 1958 29.4 100 22
72.9 25.73 0.018 0.15 1.2 71.9 8.3 1630 196 29.3 100 23 87.2 9.33
0.018 0.05 3.4 85.4 2.8 1085 391 19.5 100 24 85 12.14 0.018 0.04
2.8 83.5 2.2 1141 514 20.5 100 25 88.3 8.61 0.017 0.05 3 86.7 2.9
1036 352 17.6 100 26 64.1 31.78 0.018 0.05 0.05 63.4 2.8 1774 639
31.9 100 27 77.2 20.73 0.018 0.05 0.1 73.6 2.8 1168 421 21.0 100 28
73 25.71 0.022 0.026 1.2 72.3 1.2 1332 1127 29.3 100 29 70.2 29.63
0.018 0.05 0.05 70.0 2.8 1655 596 29.8 100 30 65.1 33.94 0.019 0.05
0.8 64.5 2.6 1913 727 36.3 100 31 77.8 20.09 0.018 0.05 0.5 72.1
2.8 1200 432 21.6 100 32 78 19.80 0.015 0.06 2.1 76.8 4.0 1740 435
26.1 100 33 74.3 23.68 0.018 0.06 1.4 72.5 3.3 1549 465 27.9
100
TABLE-US-00002 TABLE 2 Area Copper ratio alloy Alloy composition
(mass %) (%) No. Cu Zn Zr P Sn f0 f1 F2 f3 f4 .alpha. + .gamma. +
.delta. Comparative 101 93.8 0.0003 0.06 6.1 90.6 200.0 61000 305
18.3 100 102 93.6 0.0013 0.21 6.1 89.9 161.5 14077 87 18.3 100 103
92 0.035 7.9 88.1 0 677 23.7 100 104 91.9 0.0004 0.05 8 87.8 125.0
60000 480 24.0 100 105 91.8 0.0015 0.23 7.9 87.2 153.3 15800 103
23.7 100 106 89.8 0.0008 0.06 10.1 84.6 75.0 37875 505 30.3 100 107
89.8 0.004 10.1 84.8 0 758 30.3 100 108 89.8 0.019 0.008 10.1 84.7
0.4 1595 3788 30.3 100 109 89.6 0.07 0.06 10.2 84.3 0.9 437 510
30.6 100 110 89.8 0.038 0.014 10.2 84.7 0.4 805 2186 30.6 100 111
73 25.74 0.06 1.2 72.2 489 29.3 100 112 73.1 25.62 0.0007 0.08 1.2
72.3 114.3 41742 365 29.2 100 113 72.8 25.97 0.023 0.008 1.2 72.2
0.3 1286 3696 29.6 100 114 73 25.77 0.035 1.2 72.4 0 839 29.4 100
115 88 8.55 0.0008 0.05 3.4 86.2 62.5 23437 375 18.7 100 116 60
38.72 0.018 0.06 1.2 59.2 3.3 2351 705 42.3 84
TABLE-US-00003 TABLE 3 MEAN MAXIMUM COPPER GRAIN CORROSION HOT COLD
ALLOY PRIMARY SIZE TATUR DEPTH PROCESS- PROCESS- No. CRYSTAL
(.mu.m) TEST (.mu.m) IBILITY IBILITY EMBODI- 1 .alpha. 150
.largecircle. .largecircle. .largecircle. MENT 2 .alpha. 70
.largecircle. .largecircle. .largecircle. 3 .alpha. 50
.largecircle. .largecircle. .largecircle. 4 .alpha. 55
.largecircle. .DELTA. .largecircle. 5 .alpha. 20 .largecircle.
.largecircle. .largecircle. 6 .alpha. 25 .largecircle.
.largecircle. .largecircle. 7 .alpha. 35 .largecircle. .DELTA.
.largecircle. 8 .alpha. 75 .largecircle. .DELTA. .largecircle. 9
.alpha. 15 .largecircle. .largecircle. 10 .alpha. 20 .largecircle.
.DELTA. 11 .alpha. 20 .largecircle. .largecircle. .largecircle. 12
.alpha. 25 .largecircle. .DELTA. .largecircle. 13 .alpha. 25
.largecircle. .largecircle. .largecircle. 14 .alpha. 90
.largecircle. 10 OR LESS .largecircle. .largecircle. 15 .alpha. 80
.largecircle. 30 .largecircle. .largecircle. 16 .alpha. 150
.largecircle. 60 .DELTA. .largecircle. 17 .alpha. 75 .largecircle.
10 OR LESS .largecircle. .largecircle. 18 .alpha. 35 .largecircle.
10 OR LESS .largecircle. .largecircle. 19 .alpha. 30 .largecircle.
10 OR LESS .largecircle. .largecircle. 20 .alpha. 90 .largecircle.
20 .largecircle. .largecircle. 21 .alpha. 200 .largecircle. 70
.DELTA. .largecircle. 22 .alpha. 120 .largecircle. 40 .largecircle.
.DELTA. 23 .alpha. 90 .largecircle. .DELTA. .largecircle. 24
.alpha. 75 .largecircle. .largecircle. .largecircle. 25 .alpha. 80
.largecircle. .largecircle. .largecircle. 26 .alpha. 45
.largecircle. .largecircle. .largecircle. 27 .alpha. 35
.largecircle. .largecircle. .largecircle. 28 .alpha. 120
.largecircle. 30 .DELTA. .largecircle. 29 .alpha. 50 .largecircle.
20 .largecircle. .largecircle. 30 .alpha. 45 .largecircle. 20
.largecircle. .largecircle. 31 .alpha. 55 .largecircle. 10
.largecircle. .largecircle. 32 .alpha. 50 .largecircle.
.largecircle. .largecircle. 33 .alpha. 35 .largecircle. 20
.largecircle. .largecircle. CORROSION SEMI- COPPER EROSION TEST
TENSILE PROOF ELON- SOLID ALLOY MASS LOSS STRENGTH STRESS GATION
METAL No. (mg/cm.sup.2) (N/mm.sup.2) (N/mm.sup.2) (%) CASTABILITY
EMBODI- 1 MENT 2 346 136 42 .DELTA. 3 366 144 44 4 21 362 139 38 5
20 377 164 42 .largecircle. 6 388 172 43 7 381 165 43 8 363 142 39
9 10 11 12 13 14 15 16 323 105 28 17 324 115 36 18 21 349 138 38
.largecircle. 19 21 354 142 38 .largecircle. 20 326 113 35 21 311
106 28 22 302 112 17 23 24 25 26 475 174 30 27 22 375 138 34
.largecircle. 28 318 110 34 29 30 31 21 398 136 33 32 33
TABLE-US-00004 TABLE 4 MEAN MAXIMUM COPPER GRAIN CORROSION HOT COLD
ALLOY PRIMARY SIZE TATUR DEPTH PROCESS- PROCESS- No. CRYSTAL
(.mu.m) TEST (.mu.m) IBILITY IBILITY COMPARATIVE 101 .alpha. 800
.DELTA. .DELTA. .DELTA. EXAMPLE 102 .alpha. 800 .DELTA. .DELTA.
.DELTA. 103 .alpha. 450 .DELTA. X .DELTA. 104 .alpha. 700 .DELTA. X
.DELTA. 105 .alpha. 700 .DELTA. X .DELTA. 108 .alpha. 350 .DELTA. X
.DELTA. 107 .alpha. 600 X .DELTA. X 108 .alpha. 500 X X X 109
.alpha. 350 .DELTA. .DELTA. 110 .alpha. 350 .DELTA. .DELTA. 111
.alpha. 1200 .DELTA. 100 .DELTA. 112 .alpha. 1000 .DELTA. 110
.DELTA. 113 .alpha. 600 .DELTA. 130 .DELTA. 114 .alpha. 450 .DELTA.
220 .DELTA. 115 .alpha. 1000 .DELTA. X 116 .beta. 1000 .DELTA. 400
.largecircle. X CORROSION SEMI- COPPER EROSION TEST PROOF TENSILE
ELON- SOLID ALLOY MASS LOSS STRESS STRENGTH GATION METAL No.
(mg/cm.sup.2) (N/mm.sup.2) (N/mm.sup.2) (%) CASTABILITY COMPARATIVE
101 311 96 33 EXAMPLE 102 314 95 32 103 328 110 31 X 104 323 106 33
105 325 107 34 108 322 119 26 107 28 324 125 24 X 108 321 120 25
109 347 128 36 110 327 123 28 111 25 289 98 18 X 112 24 292 99 19 X
113 27 298 109 18 X 114 31 303 108 17 X 115 116 40
INDUSTRIAL APPLICABILITY
[0095] The copper alloy according to the invention is used as,
specifically, the following casting product, plastic-worked
product, that is, plastic-worked casting product, or structural
material thereof. For example, the casting product includes gear,
worm gear, bearing, bush, impeller, common mechanical parts, metal
fitting for water contact, joint or the like or the structural
materials thereof, and the plastic-worked product includes
electronicelectric device spring, switch, lead frame, connector,
bellow, fuse grip, bush, relay, gear, cam, joint, flange, bearing,
machine screw, bolt, nut, hatome, heat exchanger tube sheet, heat
exchanger, metallic mesh, sea, net, breeding net, fish net, header
material, washer, seawater condenser tube, ship parts shaft,
seawater intake of a ship or metal fitting for water contact or
like or the structural material thereof.
* * * * *