U.S. patent application number 12/278921 was filed with the patent office on 2010-07-01 for phosphor-bronze alloy as raw materials for semi solid metal casting.
This patent application is currently assigned to Mitsubishi Shindoh Co., Ltd.. Invention is credited to Keiichiro Oishi.
Application Number | 20100166595 12/278921 |
Document ID | / |
Family ID | 38371451 |
Filed Date | 2010-07-01 |
United States Patent
Application |
20100166595 |
Kind Code |
A1 |
Oishi; Keiichiro |
July 1, 2010 |
PHOSPHOR-BRONZE ALLOY AS RAW MATERIALS FOR SEMI SOLID METAL
CASTING
Abstract
A phosphor-bronze alloy as raw materials for Semi Solid Metal
casting has a component composition containing Sn of 4 to 15 mass
%, Zr of 0.0005 to 0.04 mass %, P of 0.01 to 0.25 mass %, and a
balance of Cu and inevitable impurities, further containing Zn of
0.1 to 7.5 mass % as needed, and further containing one or more
kinds of Pb of 0.01 to 4.5 mass %, Bi of 0.01 to 3.0 mass %, Se of
0.03 to 1.0 mass %, and Te of 0.01 to 1.0 mass % as needed.
Inventors: |
Oishi; Keiichiro; (Osaka,
JP) |
Correspondence
Address: |
Leason Ellis LLP
81 Main Street, Suite 503
White Plains
NY
10601
US
|
Assignee: |
Mitsubishi Shindoh Co.,
Ltd.
Tokyo
JP
|
Family ID: |
38371451 |
Appl. No.: |
12/278921 |
Filed: |
February 9, 2007 |
PCT Filed: |
February 9, 2007 |
PCT NO: |
PCT/JP2007/052403 |
371 Date: |
August 8, 2008 |
Current U.S.
Class: |
420/472 |
Current CPC
Class: |
B22D 17/007 20130101;
B22D 21/025 20130101; C22C 9/04 20130101; C22C 9/02 20130101 |
Class at
Publication: |
420/472 |
International
Class: |
C22C 9/02 20060101
C22C009/02; C22C 9/04 20060101 C22C009/04; C22C 9/08 20060101
C22C009/08 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 13, 2006 |
JP |
2006-035003 |
Claims
1. A phosphor-bronze alloy as raw materials for Semi Solid Metal
casting having a component composition containing Sn of 4 to 15
mass %, Zr of 0.0005 to 0.04 mass %, P of 0.01 to 0.25 mass %, and
a balance of Cu and inevitable impurities.
2. A phosphor-bronze alloy as raw materials for Semi Solid Metal
casting, having a component composition containing Sn of 4 to 15
mass %, Zr of 0.0005 to 0.04 mass %, P of 0.01 to 0.25 mass %, Zn
of 0.1 to 7.5 mass %, and a balance of Cu and inevitable
impurities.
3. The phosphor-bronze alloy as raw materials for Semi Solid Metal
casting according to claim 1, wherein the component composition
further contains one or more kinds of Pb of 0.01 to 4.5 mass %, Bi
of 0.01 to 3.0 mass %, Se of 0.03 to 1.0 mass %, and Te of 0.01 to
1.0 mass %.
4. The phosphor-bronze alloy as raw materials for Semi Solid Metal
casting according to claim 2, wherein the component composition
further contains one or more kinds of Pb of 0.01 to 4.5 mass %, Bi
of 0.01 to 3.0 mass %, Se of 0.03 to 1.0 mass %, and Te of 0.01 to
1.0 mass %.
Description
TECHNICAL FIELD
[0001] The present invention relates to a phosphor-bronze alloy as
raw materials for Semi Solid Metal casting that can be used to
produce a phosphor-bronze alloy cast having fine grains by Semi
Solid Metal casting (semi-solid alloy casting) without agitating a
molten metal.
[0002] Priority is claimed on Japanese Patent Application No.
2006-035003, filed Feb. 13, 2006, the content of which is
incorporated herein by reference.
BACKGROUND ART
[0003] A Cu--Sn copper alloy containing copper and tin as major
components and a minute amount of P is known as a phosphor-bronze
alloy. A forging phosphor-bronze alloy having a component
composition containing Sn of 3.5 to 9.0 mass %, phosphor of 0.03 to
0.35 mass %, and a balance of Cu and inevitable impurities and a
casting phosphor-bronze alloy having a component composition
containing Sn of 9.0 to 15.0 mass %, phosphor of 0.05 to 0.5 mass
%, and a balance of Cu and inevitable impurities are defined in the
JIS standard.
[0004] When the phosphor-bronze alloys are melted and cast by the
use of known methods, dendritic .alpha. primary crystals are
crystallized in the molten phosphor-bronze alloys and thus the
flowability of the molten alloy is poor, thereby deteriorating the
casting property at a low temperature. In order to solve this
problem, when a slurry-phase semi-solid phosphor-bronze alloy is
produced by strongly agitating the molten phosphor-bronze alloy in
a temperature range between the liquidus temperature and the
solidus temperature and the semi-solid phosphor-bronze alloy is
cast, dendrite generated in the solid-liquid mixture slurry is
segmentalized by the agitation and the .alpha. primary crystal
solid in the solid-liquid mixture slurry is formed in a sphere,
thereby maintaining the flowability at a high solid phase ratio.
Accordingly, a method of casting a phosphor-bronze alloy cast
having a structure including fine grains and granular crystals has
been suggested, which is termed a Semi Solid Metal casting method
(see Patent Document 1).
[0005] [Patent Document 1] Japanese Unexamined Patent Publication
No. H6-234049
DISCLOSURE OF THE INVENTION
Problems to be Solved by the Invention
[0006] However, in executing the Semi Solid Metal casting method in
which the molten metal is agitated, since it is necessary to
perform the agitation under the control of a molten metal
temperature, an apparatus needs to be increased in size.
Accordingly, superfluous gas may be introduced into the molten
metal under some conditions. The molten metal temperature needs to
be lowered in consideration of wear damage. However, the generation
of the dendrite structure cannot be completely suppressed even when
the known phosphor-bronze alloy is agitated in a semi-solid state.
Accordingly, the flowability of the molten metal is markedly
deteriorated, thereby finally causing casting failure.
[0007] The invention is contrived in view of the above-mentioned
problems. An object of the invention is to provide a
phosphor-bronze alloy as raw materials for Semi Solid Metal casting
that can produce a phosphor-bronze alloy cast having fine grains by
Semi Solid Metal casting without using a member for agitating the
molten metal.
Means for Solving the Problems
[0008] Therefore, the inventors studied in order to enhance the
flowability of the semi-solid phosphor-bronze alloy without using
an agitating member for segmentalizing and granulating dendrite in
a liquid phase and to produce a phosphor-bronze alloy cast having
fine grains without casting failure even when the semi-solid
phosphor-bronze alloy is cast at a low temperature. As a result,
the following observations (A) to (D) were found,
[0009] (A) A semi-solid phosphor-bronze alloy obtained by using a
phosphor-bronze alloy, which was obtained by adding Zr of 0.0005 to
0.04 mass % to a phosphor-bronze alloy containing Sn of 4 to 15
mass % and P of 0.01 to 0.25 mass %, as a raw alloy, completely
melting the phosphor-bronze alloy into a liquid phase, and cooling
the molten phosphor-bronze alloy, and a semi-solid phosphor-bronze
alloy obtained by re-melting the ingot are both excellent in
flowability. Accordingly, it was found that it is possible to
produce a phosphor-bronze alloy cast having fine grains by casting
the semi-solid phosphor-bronze alloy and that it is not necessary
to perform an agitation process in a semi-solid alloy, unlike in
the case of known examples.
[0010] (B) A semi-solid phosphor-bronze alloy obtained by using a
phosphor-bronze alloy, which was obtained by adding Zn of 0.1 to
7.5 mass % to the phosphor-bronze alloy according to (A) containing
Zr of 0.0005 to 0.04 mass % and P of 0.01 to 0.25 mass % as a raw
alloy, completely melting the phosphor-bronze alloy into a liquid
phase, and cooling the molten phosphor-bronze alloy, and a
semi-solid phosphor-bronze alloy obtained by re-melting the ingot
are both excellent in flowability. Accordingly, it was found that
it is possible to produce a phosphor-bronze alloy cast having fine
grains by casting the semi-solid phosphor-bronze alloy and that it
is not necessary to perform an agitation process in a semi-solid
alloy unlike in the case of known examples.
[0011] (C) It was found that a phosphor-bronze alloy having a
component composition further containing one or more kinds of Pb of
0.01 to 4.5 mass %, Bi of 0.01 to 3.0 mass %, Se of 0.03 to 1.0
mass %, and Te of 0.01 to 1.0 mass % in addition to the
phosphor-bronze alloy according to (A) or (B) exhibits the same
advantages.
[0012] (D) It was found that the reason for the excellent
flowability in the semi-solid alloy state of the phosphor-bronze
alloy according to (A), (B), or (C) is that fine and granular
.alpha. primary crystals are crystallized instead of dendrite in
the course of cooling and solidifying the phosphor-bronze alloy
according to (A), (B), or (C) after completely melting the
phosphor-bronze alloy into a liquid phase and that fine and
granular .alpha. primary crystals coexist in the liquid phase of
the semi-solid phosphor-bronze alloy obtained by re-melting the
phosphor-bronze alloy according to (A), (B), or (C).
[0013] The invention provides the following based on the
above-mentioned study result:
[0014] (1) A phosphor-bronze alloy as raw materials for Semi Solid
Metal casting, having a component composition containing Sn of 4 to
15 mass %, Zr of 0.0005 to 0.04 mass %, P of 0.01 to 0.25 mass %
and a balance of Cu and inevitable impurities.
[0015] (2) A phosphor-bronze alloy as raw materials for Semi Solid
Metal casting, having a component composition containing Sn of 4 to
15 mass %, Zr of 0.0005 to 0.04 mass %, P of 0.01 to 0.25 mass %,
Zn of 0.1 to 7.5 mass %, and a balance of Cu and inevitable
impurities.
[0016] (3) The component composition of the phosphor-bronze as raw
materials for Semi Solid Metal casting according to (1) or (2) may
have a component composition further containing one or more kinds
of Pb of 0.01 to 4.5 mass %, Bi of 0.01 to 3.0 mass %, Se of 0.03
to 1.0 mass %, and Te of 0.01 to 1.0 mass %.
Advantages of the Invention
[0017] When the phosphor-bronze alloy as raw materials for Semi
Solid Metal casting according to the invention is melted to produce
a semi-solid phosphor-bronze alloy in a solid-liquid mixture slurry
and the semi-solid phosphor-bronze alloy is cast using a
conventional method, a fine and granular .alpha. primary phase is
generated or an .alpha. solid phase coexists in the liquid phase of
the semi-solid phosphor-bronze alloy. Accordingly, even when an
agitating apparatus is not used, it is possible to cast the
semi-solid phosphor-bronze alloy without damaging the flowability
of the semi-solid phosphor-bronze alloy. In addition, it is an
advantage that the crystal grains of the phosphor-bronze alloy cast
obtained by casting the semi-solid phosphor-bronze alloy are
further reduced in size, thereby further enhancing the mechanical
strength.
BEST MODE FOR CARRYING OUT THE INVENTION
[0018] Hereinafter, the invention will be described in detail.
[0019] A phosphor-bronze alloy as raw materials for Semi Solid
Metal casting according to the invention has a component
composition containing Sn of 4 to 15 mass %, Zr of 0.0005 to 0.04
mass %, P of 0.01 to 0.25 mass %, and a balance of Cu and
inevitable impurities.
[0020] The phosphor-bronze alloy as raw materials for Semi Solid
Metal casting according to the invention may have a component
composition containing Sn of 4 to 15 mass %, Zr of 0.0005 to 0.04
mass %, P of 0.01 to 0.25 mass %, Zn of 0.1 to 7.5 mass % and a
balance of Cu and inevitable impurities.
[0021] The component composition of the phosphor-bronze alloy as
raw materials for Semi Solid Metal casting according to the
invention may contain Sn of 4 to 15 mass %, Zr of 0.0005 to 0.04
mass %, P of 0.01 to 0.25 mass %, Zn of 0.1 to 7.5 mass %, and a
balance of Cu and inevitable impurities.
[0022] An ingot of the phosphor-bronze alloy as raw materials for
Semi Solid Metal casting according to the invention, the component
composition of which is adjusted, is produced and stored in
advance, a semi-solid phosphor-bronze alloy is produced by
re-melting a necessary amount of the ingot of the phosphor-bronze
alloy as raw materials, and a semi-solid phosphor-bronze alloy cast
having fine grains can be manufactured by casting the semi-solid
phosphor-bronze alloy.
[0023] The reasons for defining the component composition of the
raw materials phosphor-bronze alloy for Semi Solid Metal casting
according to the invention as described above will be
described.
[0024] Sn:
[0025] Sn has a function of improving the flowability of the molten
alloy by means of addition to Cu, improving the corrosion
resistance of the cast, and improving the mechanical strength and
the wear resistance. When the content is less than 4 mass %, it is
not preferable because the mechanical strength is small and the
flowability of the molten alloy is reduced. On the other hand, when
the content is greater than 15 mass %, it is not preferable because
the casting property is deteriorated and the resultant cast is hard
and brittle, thus reducing the mechanical strength. Accordingly,
the content of Sn contained in the phosphor-bronze alloy for Semi
Solid Metal casting according to the invention is defined in the
range of 4 mass % to 15 mass %.
[0026] Zr:
[0027] With its coexistence with P, Zr has a function of promoting
the generation of fine and granular .alpha. primary crystals in a
semi-solid state, improving the flowability of the semi-solid
phosphor-bronze alloy, and reducing the size of the crystal grains
of the phosphor-bronze alloy cast, When the content thereof is less
than 0.0005 mass %, it is not preferable because the reduction in
size of the crystal grains is not sufficient. On the other hand,
when the content is greater than 0.04 mass %, it is not preferable
because the crystal grains of the cast increase in size.
Accordingly, the content of Zr contained in the phosphor-bronze
alloy as raw materials for Semi Solid Metal casting according to
the invention is defined in the range of 0.0005 mass % to 0.04 mass
%.
[0028] P:
[0029] With the coexistence of Zr, P has a function of promoting
the generation of fine granular .alpha. primary crystals in a
semi-solid state, improving the flowability of the semi-solid
phosphor-bronze alloy, and reducing the size of the crystal grains
of the phosphor-bronze alloy cast. When the content thereof is less
than 0.01 mass %, it is not preferable because the reduction in
size of the crystal grains is not sufficient. On the other hand,
when the content is greater than 0.25 mass %, it is not preferable
because intermetallic compounds with a low melting point are
generated, making it brittle. Accordingly, the content of P
contained in the phosphor-bronze alloy for Semi Solid Metal casting
according to the invention is defined in the range of 0.01 mass %
to 0.25 mass %. Zn:
[0030] Zn has a function of further improving the flowability of
the semi-solid phosphor-bronze alloy, lowering the melting point,
and enhancing the corrosion resistance and is thus added as needed.
When the content thereof is less than 0.1 mass %, it is not
preferable because the desired effect is not obtained. On the other
hand, when the content thereof is greater than 7.5 mass %, it is
not preferable because the flowability of the resultant cast is
deteriorated. Accordingly, the content of Zn contained in the
phosphor-bronze alloy as raw materials for Semi Solid Metal casting
according to the invention is defined in the range of 0.1 mass % to
7.5 mass %.
[0031] Other components:
[0032] The phosphor-bronze alloy as raw materials for Semi Solid
Metal casting according to the invention may further contain one or
more kinds of Pb, Bi, Se, and Te and the like as needed. When the
components are contained in the phosphor-bronze alloy, it is
preferable that the content of Pb be in the range of 0.01 mass % to
4.5 mass %, the content of Bi be in the range of 0.01 mass % to 3.0
mass %, the content of Se be in the range of 0.03 mass % to 1.0
mass %, and the content of Te be in the range of 0.01 mass % to 1.0
mass %.
[0033] By making the phosphor-bronze alloy as raw materials for
Semi Solid Metal casting according to the invention have the
above-mentioned component composition, when the phosphor-bronze
alloy as raw materials for Semi Solid Metal casting is melted to
produce a semi-solid phosphor-bronze alloy in a solid-liquid
mixture slurry and the semi-solid phosphor-bronze alloy is cast
using a conventional method, a fine and granular .alpha. primary
phase is generated or an .alpha. solid phase coexists in the liquid
phase of the semi-solid phosphor-bronze alloy. Accordingly, even
when an agitating apparatus is not used, it is possible to cast the
semi-solid phosphor-bronze alloy without damaging the flowability
of the semi-solid phosphor-bronze alloy. In addition, it is an
advantage that the crystal grains of the phosphor-bronze alloy cast
obtained by casting the semi-solid phosphor-bronze alloy are
further reduced in size, thereby further enhancing the mechanical
strength.
EMBODIMENTS
Embodiment 1
[0034] By preparing conventional cathode copper as a raw material,
feeding the cathode copper into an electrical furnace, melting the
cathode copper in an atmosphere of Ar gas, adding Sn and P thereto
when the temperature of the molten copper is 1200.degree. C.,
adding Zn, Pb, Bi, Se, Te, and the like thereto as needed, and
finally adding Zr thereto, a molten phosphor-bronze alloy was
produced. By casting the molten phosphor-bronze alloy, ingots of
phosphor-bronze alloys as raw materials for Semi Solid Metal
casting (hereinafter, referred to as phosphor-bronze alloys as raw
materials according to examples of the invention) according to
Examples 1 to 75 of the invention and phosphor-bronze alloys as raw
materials for Semi Solid Metal casting (hereinafter, referred to as
phosphor-bronze alloys as raw materials according to comparative
examples) according to Comparative Examples 1 to 6, which have the
component compositions shown in Tables 1 to 6, were produced.
[0035] By melting a phosphor-bronze alloy containing Sn of 9 mass
%, P of 0.35 mass % and a balance of Cu and inevitable impurities
and being available on the market and a phosphor-bronze alloy
containing Sn of 6 mass %, P of 0.1 mass % and a balance of Cu and
inevitable impurities and being available on the market in an
atmosphere of Ar gas, molten phosphor-bronze alloys of a
temperature of 1200.degree. C. were produced. By casting the molten
phosphor-bronze alloy, ingots of phosphor-bronze alloys as raw
materials for Semi Solid Metal casting (hereinafter, referred to as
phosphor-bronze alloys as raw materials according to Conventional
Examples) according to Conventional Examples 1 and 2 having the
component composition shown in Table 6 were produced.
[0036] By cutting out parts of the ingots of the phosphor-bronze
alloys as raw materials according to Examples 1 to 75 of the
present invention, the phosphor-bronze alloys as raw materials
according to Comparative Examples 1 to 6, and the phosphor-bronze
alloys as raw materials according to Conventional Examples 1 and 2
and heating the cut-out ingots at a predetermined temperature
between the solidus temperature and the liquidus temperature to
re-melt the ingots, semi-solid phosphor-bronze alloys were
produced. Quenched samples were produced by rapidly quenching the
semi-solid phosphor-bronze alloys. By observing the structures of
the quenched samples with an optical microscope, the shapes of the
.alpha. solid phase coexisting with the liquid phase in the
semi-solid phosphor-bronze alloys were estimated and the average
grain sizes thereof were measured. The results are shown in Tables
1 to 6.
[0037] The average grain sizes of the .alpha. solid phase were
measured by etching the cutting surfaces of the quenched samples
with nitric acid and then observing the cutting surfaces with an
optical microscope.
TABLE-US-00001 TABLE 1 .alpha. solid phase in Phosphor- quenched
sample bronze as raw Component composition (mass %) Average grain
materials Sn Zr P Zn Pb Bi Se Te Cu shape size (.mu.m) The 1 6
0.031 0.08 -- -- -- -- -- balance granular 100 Present 2 4 0.018
0.01 -- -- -- -- -- balance granular 200 Invention 3 7 0.015 0.07
-- -- -- -- -- balance granular 50 4 8 0.0094 0.05 -- -- -- -- --
balance granular 40 5 9 0.0060 0.09 -- -- -- -- -- balance granular
30 6 10 0.0015 0.11 -- -- -- -- -- balance granular 40 7 11 0.0008
0.16 -- -- -- -- -- balance granular 70 8 12 0.028 0.13 -- -- -- --
-- balance granular 50 9 13 0.039 0.19 -- -- -- -- -- balance
granular 120 10 14 0.003 0.21 -- -- -- -- -- balance granular 30 11
15 0.0005 0.25 -- -- -- -- -- balance granular 120 12 5 0.0008 0.11
7.5 -- -- -- -- balance granular 80 13 7 0.0015 0.16 5 -- -- -- --
balance granular 50 14 9 0.0060 0.13 2.5 -- -- -- -- balance
granular 30 15 11 0.0094 0.19 0.3 -- -- -- -- balance granular
25
TABLE-US-00002 TABLE 2 .alpha. solid phase in Phosphor- quenched
sample bronze as raw Component composition (mass %) Average grain
materials Sn Zr P Zn Pb Bi Se Te Cu shape size (.mu.m) The 16 9
0.0008 0.08 -- 4.3 -- -- -- balance granular 80 Present 17 8 0.0015
0.01 -- 3.5 -- -- -- balance granular 200 Invention 18 10 0.0060
0.07 -- 2.3 -- -- -- balance granular 25 19 11 0.0094 0.05 -- 1.1
-- -- -- balance granular 25 20 4 0.015 0.09 -- 0.5 -- -- --
balance granular 100 21 7 0.018 0.11 -- 0.1 0.72 -- -- balance
granular 45 22 13 0.031 0.16 -- 0.02 0.03 0.03 -- balance granular
50 23 6 0.028 0.13 -- -- 2.43 -- -- balance granular 50 24 7 0.039
0.19 -- -- 2.35 -- -- balance granular 100 25 9 0.003 0.21 -- --
1.23 -- -- balance granular 60 26 12 0.0005 0.25 -- -- 0.66 -- --
balance granular 150 27 14 0.0003 0.11 -- -- 0.05 -- -- balance
granular 100 28 8 0.0015 0.16 -- -- 0.01 0.05 -- balance granular
90 29 10 0.0060 0.13 -- -- 0.02 0.06 0.01 balance granular 25 30 13
0.0094 0.19 -- 0.01 -- 0.03 0.01 balance granular 50
TABLE-US-00003 TABLE 3 .alpha. solid phase in Phosphor- quenched
sample bronze as raw Component composition (mass %) Average grain
materials Sn Zr P Zn Pb Bi Se Te Cu shape size (.mu.m) The 31 5
0.0008 0.08 -- -- -- 0.11 -- balance granular 120 Present 32 8
0.0015 0.01 -- 0.1 -- 0.06 -- balance granular 200 Invention 33 10
0.0060 0.07 -- -- -- 0.21 -- balance granular 30 34 11 0.0094 0.05
-- -- 0.3 0.45 -- balance granular 25 35 15 0.015 0.09 -- -- --
0.15 -- balance granular 30 36 7 0.018 0.11 -- -- -- 0.7 -- balance
granular 45 37 4 0.031 0.16 -- -- -- 1.0 -- balance granular 120 38
6 0.028 0.13 -- 0.01 0.01 0.03 0.01 balance granular 50 39 7 0.039
0.19 -- -- 0.01 -- 0.11 balance granular 100 40 9 0.003 0.21 --
0.01 -- -- 0.05 balance granular 60 41 12 0.0005 0.25 -- -- -- 0.03
0.08 balance granular 150 42 14 0.0008 0.11 -- -- -- -- 0.15
balance granular 100 43 8 0.0015 0.16 -- -- -- -- 1.0 balance
granular 90 44 10 0.0060 0.13 -- -- -- -- 0.7 balance granular 25
45 13 0.0094 0.19 -- -- -- -- 0.23 balance granular 50
TABLE-US-00004 TABLE 4 .alpha. solid phase in Phosphor- quenched
sample bronze as raw Component composition (mass %) Average grain
materials Sn Zr P Zn Pb Bi Se Te Cu shape size (.mu.m) The 46 5
0.0008 0.08 0.5 4.33 -- -- -- balance granular 100 Present 47 8
0.0015 0.01 2 3.35 -- -- -- balance granular 150 Invention 48 10
0.0060 0.07 4 2.23 -- -- -- balance granular 30 49 11 0.0094 0.05 6
1.11 0.01 -- -- balance granular 25 50 15 0.015 0.09 0.1 0.5 --
0.03 -- balance granular 50 51 7 0.018 0.11 1 0.11 -- -- 0.01
balance granular 50 52 13 0.031 0.16 4 0.05 -- -- -- balance
granular 90 53 6 0.028 0.13 7 -- 2.43 -- -- balance granular 30 54
7 0.039 0.19 2 -- 1.85 -- -- balance granular 120 55 9 0.003 0.21
0.3 -- 1.23 -- -- balance granular 60 56 12 0.0005 0.25 4 -- 0.66
0.03 -- balance granular 150 57 14 0.0008 0.11 5 -- 0.35 -- 0.01
balance granular 100 58 8 0.0015 0.16 1 -- 0.06 -- -- balance
granular 70 59 10 0.0060 0.13 3 -- 0.05 -- -- balance granular 30
60 13 0.0094 0.19 2 -- -- 0.03 0.01 balance granular 60
TABLE-US-00005 TABLE 5 .alpha. solid phase in Phosphor- quenched
sample bronze as raw Component composition (mass %) Average grain
materials Sn Zr P Zn Pb Bi Se Te Cu shape size (.mu.m) The 61 5
0.0008 0.08 2 -- -- 0.11 -- balance granular 90 Present 62 8 0.0015
0.01 0.3 0.09 0.05 0.06 -- balance granular 200 Invention 63 10
0.0060 0.07 4 -- -- 0.21 -- balance granular 30 64 11 0.0094 0.05 7
-- -- 0.15 -- balance granular 60 65 15 0.015 0.09 0.2 -- -- 0.95
-- balance granular 45 66 7 0.018 0.11 3 -- -- 0.35 -- balance
granular 50 67 13 0.031 0.16 2 -- -- 0.35 -- balance granular 100
68 6 0.028 0.13 0.5 0.05 0.05 0.03 0.01 balance granular 60 69 7
0.039 0.19 2 -- -- -- 0.11 balance granular 120 70 9 0.003 0.21 3
0.01 -- 0.03 0.05 balance granular 60 71 12 0.0005 0.25 4 -- 0.01
0.05 0.01 balance granular 150 72 14 0.0008 0.11 0.5 -- -- -- 0.15
balance granular 120 73 8 0.0015 0.16 6 -- -- -- 0.45 balance
granular 80 74 10 0.0060 0.13 3 -- -- -- 0.95 balance granular 30
75 13 0.0094 0.19 1 -- -- -- 0.23 balance granular 50
TABLE-US-00006 TABLE 6 .alpha. solid phase in Phosphor- quenched
sample bronze as raw Component composition (mass %) Average grain
materials Sn Zr P Zn Pb Bi Se Te Cu shape size (.mu.m) Comparative
1 3* 0.006 0.07 -- -- -- -- -- balance granular 400 Example 2 16*
0.006 0.07 -- -- -- -- -- balance dendrite-phase -- 3 8 0.0003*
0.07 -- -- -- -- -- balance dendrite-phase -- 4 6 0.042* 0.03 -- --
-- -- -- balance granular 400 5 10 0.015 0.008* -- -- -- -- --
balance dendrite-phase -- 6 9 0.005 0.26* -- -- -- -- -- balance
dendrite-phase -- Conventional 1 9 -- 0.35 -- -- -- -- -- balance
dendrite-phase -- 2 6 -- 0.10 -- -- -- -- -- balance dendrite-phase
-- Mark * represents a value departing from the conditions of the
present invention.
[0038] It is estimated from the results shown in Tables 1 to 6 that
the fine and granular .alpha. solid phase coexists with the liquid
phase in the semi-solid state of the phosphor-bronze alloys as raw
materials according to Examples 1 to 75 of the present invention,
since the .alpha. solid phase of all the quenched samples was
finely granular. On the other hand, it is estimated that dendrite
was generated in the semi-solid state of the phosphor-bronze alloys
as raw materials according to Conventional Examples 1 and 2, since
the .alpha. solid phase of the quenched samples of the
phosphor-bronze alloys as raw materials according to Conventional
Examples 1 and 2 was in a dendrite phase.
[0039] Accordingly, it can be seen that the semi-solid
phosphor-bronze alloys produced from the phosphor-bronze alloys as
raw materials according to Examples 1 to 75 of the present
invention were better in flowability than the semi-solid
phosphor-bronze alloys produced from the phosphor-bronze alloys as
raw materials according to Conventional Examples 1 and 2 and that
the fine and granular .alpha. solid phase was generated in the
liquid phase of the semi-solid phosphor-bronze alloys obtained by
melting the phosphor-bronze alloys as raw materials according to
Examples 1 to 75 of the present invention, thereby obtaining a cast
having fine grains even when the semi-solid phosphor-bronze alloy
is cast without agitation. It can also be seen that the
phosphor-bronze alloys as raw materials according to Comparative
Examples 1 to 6 containing Sn, Zr, and P that depart from the
conditions of the invention (the range of component composition of
the invention) are not preferable since dendrite is generated, the
reduction in size of the crystal grains is insufficient in the
semi-solid state thereof, or the alloys are brittle.
Embodiment 2
[0040] By cutting out parts of the ingots of the phosphor-bronze
alloys as raw materials according to Examples 1 to 75 of the
present invention, produced in Embodiment 1, the phosphor-bronze
alloys as raw materials according to Comparative Examples 1 to 6,
and the phosphor-bronze alloys as raw materials according to
Conventional Examples 1 and 2 and completely melting the cut-out
ingots, molten phosphor-bronze alloys in a liquid phase were
produced. Semi-solid phosphor-bronze alloys maintained at a
predetermined temperature between the solidus temperature and the
liquidus temperature were produced by cooling the molten
phosphor-bronze alloy thereafter. Quenched samples were produced by
rapidly quenching the semi-solid phosphor-bronze alloys. By
observing the structures of the quenched samples with an optical
microscope, the shapes of the .alpha. solid crystals generated in
semi-solid phosphor-bronze alloys were estimated and the average
grain sizes thereof were measured. The results were the same as
Embodiment 1.
INDUSTRIAL APPLICABILITY
[0041] When a phosphor-bronze alloy as raw materials of the present
invention for Semi Solid Metal casting is melted to produce a
semi-solid phosphor-bronze alloy in a solid-liquid mixture slurry
and the semi-solid phosphor-bronze alloy is cast using a
conventional method, a fine and granular .alpha. primary phase is
generated or an .alpha. solid phase coexists in the liquid phase of
the semi-solid phosphor-bronze alloy. Accordingly, even when an
agitating apparatus is not used, it is possible to cast the
semi-solid phosphor-bronze alloy without damaging the flowability
of the semi-solid phosphor-bronze alloy. In addition, it is an
advantage that the crystal grains of the phosphor-bronze alloy cast
obtained by Semi Solid Metal casting phosphor-bronze alloy are
further reduced in size, thereby further enhancing the mechanical
strength. Accordingly, the invention is industrially very
useful.
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