U.S. patent application number 12/593024 was filed with the patent office on 2010-08-05 for copper alloy for electrical/electronic device and method for producing the same.
Invention is credited to Tatsuhiko Eguchi, Kiyoshige Hirose, Hiroshi Kaneko, Ryosuke Matsuo, Kuniteru Mihara.
Application Number | 20100193092 12/593024 |
Document ID | / |
Family ID | 39863792 |
Filed Date | 2010-08-05 |
United States Patent
Application |
20100193092 |
Kind Code |
A1 |
Matsuo; Ryosuke ; et
al. |
August 5, 2010 |
COPPER ALLOY FOR ELECTRICAL/ELECTRONIC DEVICE AND METHOD FOR
PRODUCING THE SAME
Abstract
A copper alloy for an electrical and electronic device in
accordance with the present invention is characterized in that the
copper alloy for an electrical and electronic device includes:
nickel (Ni) between 1.5 mass % and 5.0 mass %; silicon (Si) between
0.4 mass % and 1.5 mass %; and a remaining portion formed of Cu and
an unavoidable impurity, wherein a mass ratio between Nickel (Ni)
and Silicon (Si) as Ni/Si is not smaller than two and not larger
than seven, an average crystalline grain diameter is not smaller
than 2 .mu.m and not larger than 20 .mu.m, and a standard deviation
of the crystalline grain diameter is not larger than 10 .mu.m.
Inventors: |
Matsuo; Ryosuke; (Tokyo,
JP) ; Eguchi; Tatsuhiko; (Tokyo, JP) ; Mihara;
Kuniteru; (Tokyo, JP) ; Kaneko; Hiroshi;
(Tokyo, JP) ; Hirose; Kiyoshige; (Tokyo,
JP) |
Correspondence
Address: |
Kubotera & Associates, LLC
200 Daingerfield Rd, Suite 202
Alexandria
VA
22314
US
|
Family ID: |
39863792 |
Appl. No.: |
12/593024 |
Filed: |
March 26, 2008 |
PCT Filed: |
March 26, 2008 |
PCT NO: |
PCT/JP2008/055785 |
371 Date: |
March 15, 2010 |
Current U.S.
Class: |
148/682 ;
148/414 |
Current CPC
Class: |
B03C 5/005 20130101;
C22F 1/00 20130101; C22F 1/08 20130101; H01R 13/03 20130101; C22C
9/00 20130101; B03C 5/022 20130101; C22C 9/06 20130101 |
Class at
Publication: |
148/682 ;
148/414 |
International
Class: |
C22F 1/08 20060101
C22F001/08; C22C 9/06 20060101 C22C009/06 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 26, 2007 |
JP |
2007-080266 |
Mar 25, 2008 |
JP |
2008-079256 |
Claims
1. A copper alloy for an electrical and electronic device,
comprising: Ni between 1.5 mass % and 5.0 mass %; Si between 0.4
mass % and 1.5 mass %; and a remaining portion formed of Cu and an
unavoidable impurity, wherein said copper alloy has a mass ratio of
Ni/Si not smaller than two and not larger than seven, an average
crystalline grain diameter not smaller than 2 .mu.m and not larger
than 20 .mu.m, and a standard deviation of a crystalline grain
diameter not larger than 10 .mu.m.
2. The copper alloy for the electrical and electronic device
according to claim 1, wherein said average crystalline grain
diameter is within a range not larger than 15 .mu.m, and said
standard deviation of the crystalline grain diameter is not larger
than 8 .mu.m.
3. The copper alloy for the electrical and electronic device
according to claim 1, wherein said average crystalline grain
diameter is within a range not larger than 10 .mu.m, and said
standard deviation of the crystalline grain diameter is not larger
than 5 .mu.m.
4. The copper alloy for the electrical and electronic device
according to claim 1, further comprising at least between 0.005
mass % and 2.0 mass % of one selected from the group consisting of
Mg, Sn and Zn, said remaining portion being formed of Cu and the
unavoidable impurity.
5. The copper alloy for the electrical and electronic device
according to claim 1, further comprising at least between 0.005
mass % and 2.0 mass % of one selected from the group consisting of
Ag, Co, Cr, Fe, Mn, P, Ti and Zr, said remaining portion being
formed of Cu and the unavoidable impurity.
6. A method for producing a copper alloy for an electrical and
electronic device, comprising at least a step a, a step b, and a
step c as follows: the step a of casting a copper alloy including
Ni between 1.5 mass % and 5.0 mass %; Si between 0.4 mass % and 1.5
mass %; and a remaining portion formed of Cu and an unavoidable
impurity, said copper alloy having a mass ratio of Ni/Si not
smaller than two and not larger than seven, and performing hot
working and cold working; the step b of performing a
re-crystallization heat treatment with a temperature rising rate of
not slower than 10.degree. C. per second, at an end point
temperature between 700.degree. C. and 950.degree. C., for a
retention time between five seconds and 300 seconds, and with a
cooling rate not slower than 20.degree. C. per second till
300.degree. C. after the step a; and the step b of performing an
aging precipitation after the step b.
Description
TECHNICAL FIELD
[0001] The present invention relates to a copper alloy of a
Cu--Ni--Si system for an electrical and electronic device, and to a
method for producing the same. The copper alloy is suitable for a
lead frame of an electrical and electronic device, a connector, a
terminal, a relay, a switch, or the like.
BACKGROUND ART
[0002] Conventionally, there has been widely used a copper-based
material with superior electrical and thermal conductivity such as
phosphor bronze, red brass, brass, a Corson alloy, or the like for
an electrical and electronic device. It has been required for a
material to be applied to have further improved a strength, an
electrical conductivity, an yield stress relaxation characteristic,
a bending workability, a plating ability, a pressing workability, a
heat resisting property, or the like, in accordance with a smaller
size of an electrical and electronic device or a lighter weight in
recent years. However, it is difficult to concurrently improve
properties such as the strength and the bending workability or the
strength and the electrical conductivity.
[0003] The Corson alloy is an alloy of a Cu--Ni--Si system that has
a higher strength due to a precipitation of elements such as Ni and
Si. With the alloy, it is able to satisfy characteristics required
for an electrical and electronic device. However, the Corson alloy
has insufficient bending workability under a severe condition in
which properties concurrently need to be improved.
[0004] For instance, as a copper alloy with improved bending
workability, there is proposed a substance that contains Ni between
2 and 4% (by mass), Si between 0.5 mass % and 1.0 mass %, Zn
between 0.1 mass % and 1.0 mass %, Al, Mn, Cr, or the like, sulfur
not more than 0.002 mass %, and a remaining portion comprised of Cu
and an unavoidable impurity. A size of a precipitate is not bigger
than 10 nm, and a distribution density of the precipitate is not
lower than 1.times.10.sup.5 pieces per .mu.m.sup.3, and a hardness
Hv is not softer than 220 (refer to Japanese Patent Application
Publication No. 06-184680). However, it is not able to obtain
sufficient bending workability.
[0005] Moreover, there is proposed a copper alloy plate material
that contains Ni between 4.0 mass % and 5.0 mass %, Si within a
range for a ratio of Ni/Si between four and five, and a remaining
portion formed of Cu and an unavoidable impurity. An average grain
diameter of an Ni.sub.2Si precipitate of the alloy plate material
is between 3 nm and 10 nm, and an average space of Ni.sub.2Si
precipitate is not more than 25 nm after an accelerated aging and
hardening (refer to Japanese Patent Application Publication No.
2005-089843 for instance). The alloy exhibits improved tensile
strength and electrical conductivity.
[0006] Further, there is known a copper alloy that contains Ni
between 0.4 mass % and 4.8 mass %, Si between 0.1 mass % and 1.2
mass %, Mg or the like approximately 0.3 mass %, and a remaining
portion formed of Cu and an unavoidable impurity. An average
crystalline grain diameter is not larger than 1 .mu.m, and
crystalline grains with a grain diameters smaller than 3 .mu.m
occupy an area not smaller than 90% (refer to Japanese Patent
Application Publication No. 2006-089763). The copper alloy has
improved tensile strength, electrical conductivity and
workability.
[0007] Furthermore, Japanese Patent Application Publications No.
06-184680, No. 2005-089843 and No. 2006-089763 have disclosed a
Corson alloy in which crystalline grains are minimized in order to
improve strength. However, it has not been able to improve the
electrical conductivity and the bending workability at the same
time.
DISCLOSURE OF THE INVENTION
[0008] In view of the problems mentioned above, the present
inventors have examined relations between components and
compositions of a copper alloy, an average crystalline grain
diameter, a standard deviation of a crystalline grain diameter,
bending workability, or the like. As a result, it is found out that
it becomes able to improve the bending workability without
deteriorating strength and electrical conductivity by properly
designing the relations. Moreover, further examinations are
progressed with based on the findings, and the present invention is
completed.
[0009] According to the present invention, it becomes able to
provide a copper alloy for an electrical and electronic device and
a method for producing the same as defined below.
[0010] 1. According to a first aspect of the present invention, a
copper alloy for an electrical and electronic device includes: Ni
between 1.5 mass % and 5.0 mass %; Si between 0.4 mass % and 1.5
mass %; and a remaining portion formed of Cu and an unavoidable
impurity, wherein a mass ratio of Ni/Si is not smaller than two and
not larger than seven, an average crystalline grain diameter is not
smaller than 2 .mu.m and not larger than 20 .mu.m, and a standard
deviation of the crystalline grain diameter is not larger than 10
.mu.m.
[0011] 2. According to a second aspect of the present invention, in
the copper alloy for the electrical and electronic device in the
first aspect, the average crystalline grain diameter is within a
range not larger than 15 .mu.m, and the standard deviation of the
crystalline grain diameter is not larger than 8 .mu.m.
[0012] 3. According to a third aspect of the present invention, in
the copper alloy for the electrical and electronic device in the
first aspect, the average crystalline grain diameter is within a
range not larger than 10 .mu.m, and the standard deviation of the
crystalline grain diameter is not larger than 5 .mu.m.
[0013] 4. According to a fourth aspect of the present invention,
the copper alloy for the electrical and electronic device in one of
the first to the third aspects further includes at least one
element between 0.005 mass % and 2.0 mass %, that is selected from
a group of Mg, Sn and Zn, and a remaining portion formed of Cu and
an unavoidable impurity.
[0014] 5. According to a fifth aspect of the present invention, the
copper alloy for the electrical and electronic device in one of the
first to the fourth aspects further includes at least one element
between 0.005 mass % and 2.0 mass %, that is selected from a group
of Ag, Co, Cr, Fe, Mn, P, Ti and Zr, and a remaining portion formed
of Cu and an unavoidable impurity.
[0015] 6. According to a sixth aspect of the present invention, a
method for producing a copper alloy for an electrical and
electronic device comprises at least the following steps of:
casting a copper alloy which includes: Ni between 1.5 mass % and
5.0 mass %; Si between 0.4 mass % and 1.5 mass %; and a remaining
portion formed of Cu and an unavoidable impurity, wherein a mass
ratio of Ni/Si is not smaller than two and not larger than seven,
and performing thereafter a hot working and then performing a cold
working (Step a); performing a process of a re-crystallization heat
treatment after performing the above defined Step a, with a
temperature rising rate of not slower than 10.degree. C. per
second, to an end point temperature between 700.degree. C. and
950.degree. C., with a retention time between five seconds and 300
seconds, and with a cooling rate till 300.degree. C. as not slower
than 20.degree. C. per second (Step b); and performing a process of
an aging precipitation after performing the above defined Step b
(Process C).
[0016] In the present invention, the average crystalline grain
diameter means an average value of the grain diameter of the
individual crystals that exist in the texture of the copper alloy
after the process to be solution heated and then to be
recrystallized. Moreover, the standard deviation of the crystalline
grain diameter means a value that is evaluated with based on the
individual crystalline grain diameters. Further, the texture of the
metal has a state obtained by performing the process of treating
with heat (the process to be recrystallized), or by performing the
processes of treating with heat, of aging, of annealing, or the
like. It is able to observe the individual states by an optical
microscope (OM), a scanning electron microscope (SEM), or the
like.
[0017] The aspects and advantages in accordance with the present
invention will be further clarified by the following
description.
BEST MODE FOR CARRYING OUT THE INVENTION
[0018] In the copper alloy in accordance with the present invention
there becomes to be improved in particular the bending workability
by specifying properly the average crystalline grain diameter of
the copper alloy of Cu--Ni--Si system and the standard deviation of
the crystalline grains. And hence the alloy becomes useful for the
application to an electrical and electronic device. Next, the
functions in accordance with the component elements, the advantages
and each of the contents that comprise the copper alloy for an
electrical and electronic device in accordance with the present
invention will be described in detail below.
[0019] Ni and Si contribute to an improvement of the strength by
being precipitated as a chemical compound of Ni--Si. The reason
that such Ni is designed to be specified between 1.5 mass % and 5.0
mass % and that Si is designed to be specified between 0.4 mass %
and 1.5 mass % is that it is not able to obtain the strength as
sufficiently if ether one is lower than each of the lower limits,
respectively, or that the strength becomes to be saturated if ether
one is higher than each of the upper limits respectively, and also
that the electrical conductivity becomes to be decreased either.
Moreover, a balance between the strength and the electrical
conductivity becomes to be worsened drastically in a case where the
ratio of Ni/Si is not within the range between two and seven. The
substance is not applicable to an alloy for an electrical and
electronic device that is required to have a strength as higher and
an electrical conductivity as higher as well.
[0020] Further, regarding the copper alloy in accordance with the
present invention it becomes able to improve a material property by
being contained at least any one nature of the elements that is
selected from Mg, Sn and Zn in addition to the above mentioned
alloy contents. For example in a case of adding Mg, the same
contributes to an improvement of the stress relaxation
characteristic. Sn contributes to an improvement of the stress
relaxation characteristic and an enhancement of the strength as
well in a case of adding the same. Meanwhile, Zn contributes to an
improvement of a plating wettability thereon in a case of adding
the same. On the contrary thereto in a case where each of the
contents of the elements is excessively lower, it is not able to
obtain each of the advantages. Still further, in a case where each
of the contents is excessively higher, such as regarding the Mg
there becomes to be increased an amount of oxides at a period of a
process of casting, and then it becomes more difficult to perform
the process of casting. Still further, regarding Sn, there becomes
to be a cause to occur a crack at a period of a process of hot
working, due to segregation at a period of the process of casting.
Still further, regarding Zn, it is not able to predict any further
improvement of the plating adherence thereon. Furthermore, any one
of the sample substance is not desirable due to an occurrence of a
drastic decreasing of the individual electrical conductivities
respectively. Here regarding the copper alloy in accordance with
the present invention, it is able to produce simply by selecting
properly such as a condition of a process of a hot rolling, a
condition of a process of a cold rolling, a condition of a process
of a treating with heat to be recrystallized, a condition of a
process of a treating with heat for aging, a condition of a final
rolling, or the like.
[0021] Moreover, it becomes able to further improve the material
property by being contained as preferably at least any one nature
of the elements that is selected from a group of Ag, Co, Cr, Fe,
Mn, P, Ti and Zr in addition to the above mentioned alloy contents
in the above mentioned alloy. For example in a case of adding any
one of Ag, Co and Cr, each of the elements contributes to an
improvement of the bending workability and the strength, due to an
effect of suppressing the grain diameters from becoming rougher and
larger at a period of a process of treating with heat to be
crystallized, because of being formed a chemical compound. While,
any one of Fe, Ti and Zr contributes to an improvement of the
strength in a case of adding each of the same, because of being
formed a chemical compound. Meanwhile, phosphorus contributes to
suppress an amount of any of oxides at a period of a process of
casting in a case of adding the same. Further, Mn contributes to an
improvement of the workability of a hot working in a case of adding
the same. On the contrary thereto in a case where each of the
contents of the elements is excessively lower, it is not able to
obtain each of the advantages. Still further, in a case where each
of the contents is excessively higher, regarding Ag, there becomes
to bring about a problem from a point of view of manufacturing cost
on the production. Still further, regarding Co, it is not able to
predict any further improvement of the material property, due to
the further difficulty of performing the process of treating with
heat as sufficiently in order to solution heat the same. Still
further, Cr gives rise to a saturation of the effect of suppressing
the crystalline grain diameter from rougher and larger. Still
further, Fe gives rise to a decrease of the electrical
conductivity. Still further, one of Ti and Zr gives rise to a
further difficulty of casting, or the same becomes a cause for a
crack to be occurred at the period of the process of hot working,
due to an amount of any of oxides as excessively larger at a period
of a process of casting. Still further, Mn gives rise to a decrease
of the electrical conductivity either. Still further, phosphorus
gives rise to a deterioration of the bending workability due to an
increase of the precipitate. Furthermore, any one of the sample
substances is not desirable due to an occurrence of a drastic
decreasing of the individual electrical conductivities
respectively. Here regarding the copper alloy in accordance with
the present invention, it is able to produce simply by selecting
properly such as a condition of a process of a hot rolling, a
condition of a process of a cold rolling, a condition of a process
of a treating with heat to be recrystallized, a condition of a
process of a treating with heat for aging, a condition of a final
rolling, or the like.
[0022] Next, regarding a method for producing the copper alloy for
an electrical device and an electronic device that have the average
crystalline grain diameter and the standard deviation of the
crystalline grain diameter, a preferred embodiment will be
described in detail below.
[0023] Here regarding a method for producing the copper alloy in
accordance with the present embodiment, it is desirable to comprise
the above defined Step a, Step b and Process C, and it is further
preferable in particular to make use of the following processes
from (1) to (10) in order.
[0024] (1) Process of casting a copper alloy which includes: Ni
between 1.5 mass % and 5.0 mass %; Si between 0.4 mass % and 1.5
mass %; and a remaining portion formed of Cu and an unavoidable
impurity, wherein a mass ratio between Ni and Si as Ni/Si is not
smaller than two and not larger than seven.
[0025] (2) Process of performing a hot working and then of
performing a cold working.
[0026] (3) Process of treating with heat to be recrystallized;
[0027] (3-1) Temperature rising rate: it is desirable to design the
temperature rising rate as not slower than 10.degree. C. per second
to an end point temperature, or it is further preferable to be
designed as not slower than 10.degree. C. per second but not faster
than 100.degree. C. per second.
[0028] (3-2) End point temperature: it is desirable to be designed
between 700.degree. C. and 950.degree. C.
[0029] (3-3) Retention time: it is desirable to be designed for
between five seconds and 300 seconds.
[0030] (3-4) Cooling rate: it is desirable to be designed as not
slower than 20.degree. C. per second till 300.degree. C. for
instance, or it is further preferable to be designed as not slower
than 20.degree. C. per second but not faster than 200.degree. C.
per second.
[0031] (4) Process of aging precipitation:
[0032] (4-1) Condition of temperature rising: it is desirable for
an end point temperature to be between 300.degree. C. and
600.degree. C., for an amount of time for treating to be between
0.5 hour and ten hours, for a temperature rising rate at the period
to be as within a range between 2.degree. C. and 25.degree. C. per
minute from a room temperature till reaching to the maximum
temperature.
[0033] (4-2) Condition of cooling: it is desirable at the period of
falling the temperature to be performed within a range between 1
and 2.degree. C. per minute for the temperature as not lower than
300.degree. C. at an inside of a furnace.
[0034] (5) Process of annealing for reducing distortion: it is
desirable to perform a heating with a temperature at between
250.degree. C. and 400.degree. C. and with an amount of time for
between 0.5 hour and five hours, or it is desirable to perform a
heating with a temperature at between 600.degree. C. and
800.degree. C. and with an amount of time for between five seconds
and 60 seconds as well.
[0035] Thus, it becomes able to obtain as efficiently the copper
alloy that has the above desirable properties. Furthermore, it is
further preferable to install a process for performing a cold
working into between the above mentioned Process (4) and Process
(5), that has a rate of rolling as not higher than 30% (including
zero percent).
[0036] Next, an average crystalline grain diameter of the copper
alloy in accordance with the present invention and a standard
deviation of the crystalline grain diameter will be described in
detail below. Here regarding the copper alloy in accordance with
the present invention, the average crystalline grain diameter is
designed to be as not smaller than 2 .mu.m and not larger than 20
.mu.m. And, it is desirable to be as not larger than 15 .mu.m, or
it is further preferable to be as not larger than 10 .mu.m. Here in
a case where the average crystalline grain diameter is excessively
smaller, there is observed a remaining of the texture to be worked
at the last process, and then thereby there may be occurred a
deterioration of bending workability as drastically. Moreover, in a
case where the average crystalline grain diameter is excessively
larger on the contrary thereto, there becomes easier to be occurred
a crack thereon at a period of bending work, and then thereby there
becomes to be occurred a deterioration of bending workability. Here
the standard deviation of the average crystalline grain diameter is
designed to be as not larger than 10 .mu.m. On the contrary thereto
in a case where the deviation is excessively larger, there becomes
to be a state where the grains individually having the larger grain
diameters and the grains individually having the smaller grain
diameters are coexisting together. And then in a case where any one
of the grains individually having the larger grain diameters exists
at around a top of the bended part, there may be occurred a crack
on a bended surface, or there may be occurred a peeling of the
plating off from a part at around a corrugation as largely wrinkled
that may be created at around the grain having the larger grain
diameter at a period of bending.
[0037] Thus, the copper alloy for an electrical and electronic
device in accordance with the present invention becomes to be
superior in the strength, the electrical conductivity and in the
processing characteristics for the bending in particular. And then
it becomes able to apply the same as preferred to the usage for the
electrical device and for the electronic device, such as a lead
frame, a connector, a terminal, a relay, a switch, or the like.
Moreover, by making use of the method for producing the same in
accordance with the present invention, it becomes able to produce
further efficiently the above mentioned copper alloy for an
electrical and electronic device that has the above mentioned
superior properties. Furthermore, it becomes able to apply the
method as preferred to a mass production as well.
EXAMPLES
[0038] Next, the present invention will be described in further
detail below, in reference to the following examples, however, the
present invention will not be limited to any one of the
examples.
Example 1
[0039] There is performed an ingot of the copper alloys that
individually have the compositions as shown in the following Table
1, and then there is obtained each of the ingots that are casted
and individually have a dimension of 110 mm by 160 mm by 30 mm.
Moreover, for each of the ingots there are performed the following
processes of: maintaining at a temperature of 1000.degree. C. with
an amount of time of 30 minutes approximately; performing a work
thereon by making use of a hot rolling till obtaining the thickness
to be as 12 mm from the initial thickness of 30 mm; performing a
quenching rapidly by a water cooling; facing to become
approximately 10 mm for the thickness in order to remove a surface
oxide film layer; and performing a cold rolling to obtain the
thickness of 0.15 mm, 0.20 mm or 0.25 mm as corresponding properly
to each of the testing requirements respectively. And hence there
are assumed each of the substances as an intermediate sample.
[0040] And then for each of the above mentioned intermediate
samples there are performed the following processes of: performing
a treatment with heat to be recrystallized at each of the
temperature as shown in Table 2 with maintaining the individual
temperatures for between five seconds and 300 seconds; and then
performing a cooling rapidly by making use of the water cooling or
by an oil cooling. Moreover, there is designed for a temperature
rising rate from a room temperature till reaching to the maximum
temperature to be within a range of not slower than 10.degree. C.
per second. Further, there is designed for a cooling rate to be
within a range of not slower than 20.degree. C. per second for the
temperature as not lower than 300.degree. C.
[0041] And then thereafter for each of the above mentioned samples
of copper alloy there are performed the following processes of:
removing a surface oxide film layer; performing a cold rolling as
not more than 30% (including zero percent) as required
respectively; and then performing a treatment with heat to be aging
precipitated at a temperature between 450.degree. C. and
550.degree. C. with an amount of time for 120 minutes
approximately. Still further, there is designed for a temperature
rising rate from a room temperature till reaching to the maximum
temperature to be within a range between 2.degree. C. per minute
and 25.degree. C. per minute. Still further, there is performed
thereafter a cooling process with controlling a cooling rate to be
within a range between 1.degree. C. per minute and 2.degree. C. per
minute at an inside of a furnace for the temperature as not lower
than 300.degree. C. which influences a state of the precipitation.
And then thereafter for each of the samples there are performed the
following processes of: performing another cold rolling as not more
than 30% (including zero percent); and then performing an annealing
for reducing a distortion, by performing a heating with a
temperature at between 250.degree. C. and 400.degree. C. and with
an amount of time for between 0.5 hour and five hours, or by
performing a heating with a temperature at between 600.degree. C.
and 800.degree. C. and with an amount of time for between five
seconds and 60 seconds.
[0042] Furthermore, there is performed each of the following
characteristic evaluations regarding each of the copper alloy
materials for an electrical and electronic device as the samples
(samples of copper alloy) that are individually obtained in the
above mentioned manner.
[0043] A. Electrical Conductivity:
[0044] There is performed a measurement of a specific resistance by
making use of a four terminal method in a constant temperature bath
which is maintained at 20.degree. C. (.+-.0.5.degree. C.), and then
thereby there is calculated the electrical conductivity. Moreover,
there is assumed to be as 100 mm regarding a distance between each
of the terminals.
[0045] B. 0.2% Yield Strength and Tensile Strength:
[0046] There is performed a measurement for the test pieces for the
number five as pursuant to JIS 22201, with two pieces that are
pursuant to JIS 22241, that are cut out in a direction as parallel
to a rolling. And then there is calculated each of the average
values respectively. Moreover, there is made use of the offset
method regarding the 0.2% yield strength, meanwhile, there is
evaluated regarding the tensile strength with making use of the
numerical value for which the maximum tensile force is divided by
an original cross sectional area.
[0047] C. Average Crystalline Grain Diameter and the Distribution
Thereof (Standard Deviation):
[0048] At first there is performed a finishing for each of the test
pieces to have individual mirror finished surfaces for individual
cut faces thereon that are in a right angle to the rolling
direction, by making use of a wet polishing and then by making use
of a buffing. And then thereafter there is performed a corrosion on
the polished surfaces for a several seconds with making use of a
weak acid. Moreover, there is performed taking some photographs by
making use of an optical microscope (OM) at a magnifying power
between 50 times and 600 times and of a scanning electron
microscope (SEM) at a magnifying power between 400 times and 5000
times. And hence there is performed a measurement for a grain
diameter on the individual cut faces by making use of a crosscut
method as pursuant to JIS H0501. And then thereby there becomes to
be calculated an average grain diameter. Further, there is
evaluated a standard deviation of the grain diameters by performing
the measurement for each of the grain diameters as one by one.
Still further, there is assumed a population parameter of the
measurements as to be 200 in the case of evaluating the standard
deviation of the grain diameters. Furthermore, there is performed a
measurement of a grain diameter in a sample that is before
performing the rolling (that corresponds to the time when the
process of treating with heat to be recrystallized is finished)
regarding the grain cannot help but become to be flat after
performing the rolling in accordance with the above mentioned
measurement of the grain diameters.
[0049] D. Evaluation of Bending Workability (R/t (GW), R/t
(BW)):
[0050] At first there is performed removing of an oxide film layer
on a surface of the individual samples after performing the above
mentioned processes, that have individual board thickness (t) of
approximately 0.25 millimeter and have individual board widths (w)
of approximately ten millimeters. And then thereafter there is
performed a bending for each to have individual angles at each
inner side of the bending as ninety degrees respectively, for the
samples with the bending in parallel to the rolling direction (a GW
hereinafter), and for the other samples with the bending in a right
angle to the rolling direction (a BW hereinafter). Moreover, there
is performed an evaluation regarding the method of the evaluation
of the bending by making use of a calculation of a ratio as R/t for
which a bend radius as an R that is the minimal limit value of
which there is not occurred any one of the above mentioned minute
cracks thereon is divided by the board thickness (t). Further,
there is performed a judgment regarding an observation to confirm
whether or not there is any crack thereon, by making use of the OM
at the magnifying power between 50 times and 600 times, or by
making use of the SEM at the magnifying power between 400 times and
2000 times. When the value of R/t decreases, the bending
workability is improved.
[0051] E. Adherence of the Plating Layer:
[0052] At first there is performed a plating of bright tin to have
a thickness of approximately 1 .mu.m on each of the test pieces
that individually have the dimensions of 30 mm by 10 mm. And then
thereafter there is performed a keeping warm of each of the test
pieces in an atmosphere at a temperature of approximately
150.degree. C. with an amount of time for 1000 hours. Moreover,
there is performed thereafter a bending thereon with an angle to be
180 degrees and then the same is bended again to be an initial form
respectively. Further, there is performed an observation by
visually regarding a state of an adherence between the bended part
and the plating of tin thereon. Furthermore, there is performed a
further observation whether or not there is existed any peeling
thereon by making use of the OM at the magnifying power between 50
times and 200 times as required. Here there is judged for a test
piece that has an area ratio of peeling at the bending part as from
zero percent but smaller than 10% to be assumed as EXCELLENT, or
for a test piece that has the same as not smaller than 10% but
smaller than 30% to be assumed as GOOD, or for a test piece that
has the same as not smaller than 30% but smaller than 50% to be
assumed as ACCEPTABLE, or for a test piece that has the same as not
smaller than 50% to be assumed as NO GOOD.
[0053] F. Stress Relaxation Characteristic:
[0054] There is performed a measurement under the conditions that
there is maintained each of the test pieces with an amount of time
for 1000 hours in a constant temperature bath of 150.degree. C.
approximately, and that there is set a load stress for a surface
maximum stress thereon to have a value as an 80% of each of the
yield strengths respectively, by adopting a cantilever block method
that is pursuant to the standard specification of Electronic
Material Association of Japan (EMAS-3003).
[0055] Here regarding each of the results in accordance with the
above mentioned measurements, there is shown in Table 1 for each of
the alloy compositions regarding each of the intermediate samples,
and there is shown in Table 2 through Table 4 for each of the
results of the characteristic evaluations regarding each of the
above mentioned alloy test pieces in accordance with the copper
alloy samples.
TABLE-US-00001 TABLE 1 INTERMEDIATE Ni Si Ag Co Cr Fe Mn Mg P Sn Ti
Zn Zr SAMPLES mass % Ni/Si 1 2.308 0.559 -- -- -- -- -- -- -- -- --
-- -- 4.1 2 3.765 0.918 -- -- -- -- -- -- -- -- -- -- -- 4.1 3
2.308 0.559 -- -- -- -- -- 0.100 -- -- -- -- -- 4.1 4 2.308 0.559
-- -- -- -- -- -- -- 0.150 -- -- -- 4.1 5 2.308 0.559 -- -- -- --
-- -- -- -- -- 0.450 -- 4.1 6 2.308 0.562 -- -- -- -- -- 0.160 --
0.162 -- -- -- 4.1 7 2.318 0.558 -- -- -- -- -- -- -- 0.166 --
0.458 -- 4.2 8 2.303 0.550 -- -- -- -- -- 0.169 -- -- -- 0.455 --
4.2 9 2.310 0.561 -- -- -- -- -- 0.157 -- 0.154 -- 0.452 -- 4.1 10
3.757 0.920 -- -- -- -- -- 0.155 -- 0.156 -- 0.454 -- 4.1 11 2.308
0.790 -- -- -- -- -- 0.151 -- 0.152 -- 0.445 -- 2.8 12 2.310 0.430
-- -- -- -- -- 0.157 -- 0.155 -- 0.456 -- 5.4 13 3.770 1.150 -- --
-- -- -- 0.156 -- 0.155 -- 0.458 -- 3.3 14 3.765 0.610 -- -- -- --
-- 0.155 -- 0.161 -- 0.451 -- 6.2 15 2.314 0.565 0.118 -- -- -- --
0.164 -- 0.153 -- 0.457 -- 4.1 16 2.310 0.607 -- 0.310 -- -- --
0.168 -- 0.167 -- 0.463 -- 3.8 17 2.305 0.553 -- -- 0.162 -- --
0.158 -- 0.170 -- 0.461 -- 4.2 18 2.310 0.552 -- -- -- 0.313 --
0.152 -- 0.168 -- 0.456 -- 4.2 19 2.306 0.563 -- -- -- -- 0.202
0.169 -- 2.100 -- 0.455 -- 4.1 20 2.319 0.550 -- -- -- -- -- 0.151
0.089 0.168 -- 0.466 -- 4.2 21 2.302 0.567 -- -- -- -- -- 0.161 --
0.152 0.250 0.468 -- 4.1 22 2.303 0.552 -- -- -- -- -- 0.168 --
0.153 -- 0.466 0.300 4.2 23 2.310 0.561 -- -- -- -- -- 0.004 -- --
-- -- -- 4.1 24 2.305 0.557 -- -- -- -- -- -- -- 0.003 -- -- -- 4.1
25 2.302 0.555 -- -- -- -- -- -- -- -- -- 0.002 -- 4.1 26 2.320
0.557 -- -- -- -- -- 2.500 -- -- -- -- -- 4.2 27 2.302 0.558 -- --
-- -- -- -- -- 2.200 -- -- -- 4.1 28 2.308 0.559 -- -- -- -- -- --
-- -- -- 2.500 -- 4.1 INTERMEDIATE Ni Si Ag Co Cr Fe Mn Mg P Sn Ti
Zn Zr SAMPLES mass % 29 1.210 0.313 -- -- -- -- -- -- -- -- -- --
-- 30 6.000 1.500 -- -- -- -- -- -- -- -- -- -- -- 31 2.311 0.310
-- -- -- -- -- 0.161 -- 0.152 -- 0.451 -- 32 2.303 1.300 -- -- --
-- -- 0.164 -- 0.152 -- 0.457 -- 33 1.100 0.575 -- -- -- -- --
0.163 -- 0.153 -- 0.461 -- 34 5.085 0.580 -- -- -- -- -- 0.161 --
0.159 -- 0.458 -- 35 3.750 0.520 -- -- -- -- -- 0.161 -- 0.152 --
0.451 -- 36 3.768 1.950 -- -- -- -- -- 0.161 -- 0.159 -- 0.458 --
37 2.314 0.570 0.002 -- -- -- -- 0.164 -- 0.153 -- 0.457 -- 38
2.310 0.600 -- 0.003 -- -- -- 0.168 -- 0.167 -- 0.463 -- 39 2.311
0.566 -- -- 0.001 -- -- 0.164 -- 0.151 -- 0.454 -- 40 2.311 0.540
-- -- -- 0.001 -- 0.165 -- 0.163 -- 0.467 -- 41 2.311 0.575 -- --
-- -- 0.001 0.168 -- 0.169 -- 0.463 -- 42 2.305 0.614 -- -- -- --
-- 0.168 0.001 0.151 -- 0.488 -- 43 2.319 0.559 -- -- -- -- --
0.152 -- 0.151 0.002 0.477 -- 44 2.320 0.573 -- -- -- -- -- 0.154
-- 0.155 -- 0.455 0.001 45 2.323 0.561 2.825 -- -- -- -- 0.163 --
0.169 -- 0.468 -- 46 2.250 0.614 -- 3.001 -- -- -- 0.160 -- 0.168
-- 0.466 -- 47 2.307 0.562 -- -- 2.406 -- -- 0.160 -- 0.157 --
0.454 -- 48 2.319 0.559 -- -- -- 3.014 -- 0.159 -- 0.168 -- 0.468
-- 49 2.309 0.562 -- -- -- -- 2.108 0.159 -- 0.151 -- 0.468 -- 50
2.312 0.555 -- -- -- -- -- 0.160 2.210 0.151 -- 0.454 -- 51 2.313
0.554 -- -- -- -- -- 0.160 -- 0.151 3.207 0.468 -- 52 2.307 0.562
-- -- -- -- 0.160 -- 0.151 -- 0.468 2.516
TABLE-US-00002 TABLE 2 COPPER N RECRYSTALLIZATION TENSILE 0.2%
YIELD ELECTRICAL ALLOY INTERMEDIATE CONCENTRATION TEMPERATURE
STRENGTH STRENGTH CONDUCTIVITY SAMPLES SAMPLES (mass %) (.degree.
C.) (MPa) (MPa) (% IACS) 1 1 2.308 800 750 595 44 2 2 3.765 875 850
685 38 3 3 2.308 800 735 600 41 4 4 2.308 800 745 605 39 5 5 2.308
800 730 610 41 6 6 2.308 800 758 610 41 7 7 2.318 800 782 615 40 8
8 2.303 800 755 613 42 9 9 2.310 800 762 620 39 10 10 3.757 800 850
685 38 11 1 2.308 960 770 650 39 12 2 3.765 690 767 685 42 13 23
2.310 800 742 595 44 14 24 2.305 800 755 585 44 15 25 2.302 800 752
592 44 16 26 2.320 UNABLE TO CAST DUE TO FREQUENT OCCURRENCE OF
OXIDE) 17 27 2.302 800 749 596 15 18 28 2.308 800 751 597 28
AVERAGE STRESS COPPER CRYSTALLINE DEVIATION OF RELAXATION ALLOY
GRAIN GRAIN R/t R/t CHARACTERISTIC PLATING SAMPLES DIAMETER (.mu.m)
DIAMETER (.mu.m) (GW) (BW) (%) ADHERENCE 1 12.5 4.4 0.0 0.0 25 GOOD
2 11.2 4.3 1.3 0.8 22 GOOD 3 14.5 6.0 0.0 0.0 16 GOOD 4 13.6 5.0
0.0 0.0 20 GOOD 5 14.2 5.5 0.0 0.0 24 GOOD 6 11.8 4.0 0.0 0.0 24
GOOD 7 11.7 4.1 0.0 0.0 19 EXCELLENT 8 11.9 4.0 0.0 0.0 19
EXCELLENT 9 11.5 4.0 0.0 0.0 16 EXCELLENT 10 10.9 4.1 1.3 0.8 16
EXCELLENT 11 153.6 35.0 0.8 0.5 8 NO GOOD 12 NOT RECRYSTALLIZED 1.2
1.5 8 ACCEPTABLE 13 12.2 4.4 0.0 0.0 25 GOOD 14 12.3 4.3 0.0 0.0 25
GOOD 15 12.7 4.4 0.0 0.0 25 GOOD 16 UNABLE TO CAST DUE TO FREQUENT
OCCURRENCE OF OXIDE) 17 11.5 3.9 0.0 0.0 15 GOOD 18 11.2 3.8 0.0
0.0 22 EXCELLENT
[0056] Here in accordance with Table 2, for the samples of the
copper alloy 1 and 2 there are added Ni and Si as the contents in
the copper alloy respectively. While, for the samples of the copper
alloy 3 through 5 there is added any one nature of the elements of
Mg, Sn and Zn in addition to Ni and Si respectively. Moreover, for
the samples of the copper alloy 6 through 10 there are added at
least any two natures of the elements of Mg, Sn and Zn in addition
to Ni and Si respectively. Further, in the samples of the copper
alloy 11 and 12 there is remained a part that the crystalline grain
diameter becomes to be excessively larger due to the temperature to
be recrystallized as excessively higher, or that is not
recrystallized due to the temperature to be recrystallized as
excessively lower. Furthermore, in the samples of the copper alloy
13 through 18 the amount of addition of any one of Mg, Sn and Zn is
not within the range of the specification.
[0057] According to the result shown in Table 2, it is able to
judge that both of the samples of the copper alloy 11 and 12 as the
comparative samples in which each of the crystalline grain
diameters becomes to be excessively larger are not sufficient on a
practical use due to the plating adherence thereon, the stress
relaxation characteristic and the bending workability as inferior
thereto.
[0058] Moreover, it is found out on the contrary thereto that each
of the copper alloys in accordance with the present invention (the
samples of the copper alloy 1 through 10, and 13 through 15) has
the characteristics of alloy as sufficient on the practical use
regarding each of the items of the evaluation. Further, it is found
out as shown in the results of the copper alloy samples 7, 8, 9 and
10 in particular that there becomes to be improved the plating
adherence thereon and also there becomes to be contributed on the
improvement of the tensile strength in the case where Zn is
designed to be added as the further alloy content. Still further,
it is found out as shown in the results of the copper alloy samples
6, 8, 9 and 10 that there becomes to be improved the stress
relaxation characteristic in the case where Mg is designed to be
added. Still further, it is found out as shown in the results of
the copper alloy samples 6, 7, 9 and 10 that there becomes to be
improved the stress relaxation characteristic as well in the case
where Sn is designed to be added, and then the characteristic is
remarkable in particular regarding the copper alloy samples 9 and
10 for which Mg is designed to be added together at the same time.
Still further, it is found out as shown in the results of the
copper alloy samples 9 and 10 that there becomes to be improved in
total of the tensile strength, the stress relaxation characteristic
and the plating adherence thereon due to the addition of Mg, Sn and
Zn together at the same time. Still further, it is found out that
the improvement and then the advantages due to the above mentioned
any additions of Mg, Sn and Zn will not be appeared in a case where
the amount of any of the additions is excessively smaller (refer to
the copper alloy samples 13 through 15).
[0059] Further, in a case when Mg, Sn and Zn is added excessively,
it is found out that it is difficult for casting in the case of MG
(refer to the copper alloy sample 16), and electrical conductivity
drastically decreases in the case of Sn and Zn (refer to the copper
alloy samples 17 and 18).
TABLE-US-00003 TABLE 3 COPPER N RECRYSTALLIZATION TENSILE 0.2%
YIELD ELECTRICAL ALLOY INTERMEDIATE CONCENTRATION TEMPERATURE
STRENGTH STRENGTH CONDUCTIVITY SAMPLES SAMPLES (mass %) (.degree.
C.) (MPa) (MPa) (% IACS) 19 1 2.308 800 750 595 44 20 2 3.765 875
850 885 38 21 9 2.310 800 762 829 39 22 10 3.757 875 855 692 38 23
11 2.308 800 715 585 38 24 12 2.310 800 701 565 40 25 13 3.770 875
812 635 32 26 14 3.763 875 792 625 39 27 29 1.210 800 580 500 48 28
30 5.000 875 870 695 30 29 31 2.311 800 677 546 39 30 32 2.303 800
855 635 32 31 33 1.100 800 585 495 40 32 34 5.085 800 775 686 26 33
35 3.750 875 752 615 34 34 36 3.768 875 783 665 30 AVERAGE STRESS
COPPER CRYSTALLINE DEVIATION OF RELAXATION ALLOY GRAIIN GRAIN R/t
R/t CHARACTERISTIC PLATING SAMPLES DIAMETER (.mu.m) DIAMETER
(.mu.m) (GW) (BW) (%) ADHERENCE 19 12.5 4.4 0.0 0.0 25 GOOD 20 11.2
4.3 1.3 0.8 22 GOOD 21 11.5 4.0 0.0 0.0 16 EXCELLENT 22 10.9 4.1
1.3 0.8 16 EXCELLENT 23 11.5 4.1 0.0 0.0 16 EXCELLENT 24 12.7 4.2
0.0 0.0 16 EXCELLENT 25 10.9 4.2 1.3 0.8 16 EXCELLENT 26 10.6 4.1
1.3 0.8 16 EXCELLENT 27 50.0 12.0 0.0 0.0 30 GOOD 28 8.0 3.0 1.3
1.0 22 GOOD 29 13.5 4.6 0.0 0.0 16 EXCELLENT 30 10.5 4.1 0.0 0.0 16
EXCELLENT 31 50.2 15.5 0.2 0.2 18 EXCELLENT 32 0.0 1.2 0.2 0.2 16
EXCELLENT 33 13.3 4.6 1.3 0.8 16 EXCELLENT 34 10.2 4.1 1.3 0.8 16
EXCELLENT
[0060] Here in accordance with Table 3, there are shown for the
case where the ratio of Ni/Si is 4.1 as the copper alloy samples 19
through 22, meanwhile, there are shown for the case where the ratio
of Ni/Si is between two and seven as the copper alloy samples 23
through 26. Moreover, in order to compare and refer with making use
of the above mentioned classification in accordance with Table 3,
the table further includes some of the results as shown in Table 2
as well. Further, there are shown regarding Comparative samples as
the copper alloy samples 27 through 34, in which either one of the
contents of Ni and Si or the mass ratio is not within the range of
the specification.
[0061] Here there are compared between the samples that
individually contain Ni having the concentration as similar to
therebetween. As comparing between the copper alloy samples 23
(Example) and of the number as 30 (Comparative example), or between
the copper alloy samples 25 (Example) and of the number as 34
(Comparative example) for instance, the individual samples in
accordance with Comparative example are inferior thereto in the
tensile strength, in the 0.2% yield strength and in the electrical
conductivity respectively. Moreover, as comparing and referring
between the copper alloy samples 24 (Example) and of the number as
29 (Comparative example), or between the copper alloy samples 26
(Example) and of the number as 33 (Comparative example), the
individual samples in accordance with Comparative example have the
ratio of Ni/Si as larger than 7.0, and also each of the samples is
inferior thereto in the tensile strength and in the 0.2% yield
strength either respectively. Further, in the case where the
concentration of Ni becomes to be lower than 1.5 mass % as given in
accordance with the copper alloy samples 27 and 31 for example (for
both as Comparative examples), there is occurred the deterioration
of the tensile strength as drastically even in the case where the
ratio of Ni/Si is maintained properly. And hence in accordance with
the above mentioned results therefrom, it is found out that there
is a tendency to occur both of the decreasing of the electrical
conductivity and the deterioration of the strength in the case
where the content of Ni or the ratio of Ni/Si is not within the
range of the specification.
TABLE-US-00004 TABLE 4 COPPER N RECRYSTALLIZATION TENSILE 0.2%
YIELD ELECTRICAL ALLOY INTERMEDIATE CONCENTRATION TEMPERATURE
STRENGTH STRENGTH CONDUCTIVITY SAMPLES SAMPLES (mass %) (.degree.
C.) (MPa) (MPa) (% IACS) 35 9 2.310 800 789 710 39 36 15 2.314 800
790 715 41 37 16 2.310 800 792 725 39 38 17 2.305 800 785 723 39 39
18 2.310 800 792 722 39 40 19 2.306 800 795 735 39 41 20 2.318 800
793 724 39 42 21 2.302 800 794 728 39 43 22 2.303 800 788 725 38 44
37 2.314 800 781 711 39 45 38 2.310 800 779 712 39 46 39 2.311 800
779 708 39 47 40 2.311 800 782 709 39 48 41 2.311 800 777 708 39 49
42 2.305 800 781 709 39 50 43 2.319 800 782 711 39 51 44 2.320 800
778 711 39 52 45 2.323 800 792 718 42 53 46 2.250 UNABLE TO PROCESS
NOT WORKING (DUE TO OCCURRENCE OF CRACKING) 54 47 2.307 UNABLE TO
CAST (DUE TO FREQUENT OCCURRENCE OF OXIDE) 55 48 2.319 800 795 730
23 56 49 2.309 800 796 735 25 57 50 2.312 800 855 692 25 58 51
2.313 UNABLE TO CAST (DUE TO FREQUENT OCCURRENCE OF OXIDE) 59 52
2.307 UNABLE TO CAST (DUE TO FREQUENT OCCURRENCE OF OXIDE) AVERAGE
STRESS COPPER CRYSTALLINE DEVIATION OF RELAXATION ALLOY GRAIN GRAIN
R/t R/t CHARACTERISTIC PLATING SAMPLES DIAMETER (.mu.m) DIAMETER
(.mu.m) (GW) (BW) (%) ADHERENCE 35 11.5 4.0 0.3 0.3 16 EXCELLENT 36
8.5 3.8 0.3 0.3 16 EXCELLENT 37 4.8 1.8 0.2 0.2 16 EXCELLENT 38
10.9 4.1 0.2 0.2 16 EXCELLENT 39 10.9 4.1 0.3 0.3 16 EXCELLENT 40
10.6 4.1 0.3 0.3 16 EXCELLENT 41 10.3 3.8 0.3 0.3 16 EXCELLENT 42
8.8 2.9 0.2 0.2 16 EXCELLENT 43 8.5 2.6 0.2 0.2 16 EXCELLENT 44
11.6 4.1 0.3 0.3 16 EXCELLENT 45 11.4 3.9 0.3 0.3 16 EXCELLENT 46
11.5 3.9 0.3 0.3 16 EXCELLENT 47 11.3 4.1 0.3 0.3 16 EXCELLENT 48
11.7 4.1 0.3 0.3 16 EXCELLENT 49 11.2 4.1 0.3 0.3 16 EXCELLENT 50
11.7 4.2 0.3 0.3 16 EXCELLENT 51 11.8 4.1 0.3 0.3 16 EXCELLENT 52
10.9 4.1 0.3 0.3 16 EXCELLENT 53 UNABLE TO PROCESS NOT WORKING (DUE
TO OCCURRENCE OF CRACKING) 54 UNABLE TO CAST (DUE TO FREQUENT
OCCURRENCE OF OXIDE) 55 10.9 4.0 0.3 0.3 16 EXCELLENT 56 10.9 3.9
0.3 0.3 16 EXCELLENT 57 10.2 3.3 0.6 0.8 16 EXCELLENT 58 UNABLE TO
CAST (DUE TO FREQUENT OCCURRENCE OF OXIDE) 59 UNABLE TO CAST (DUE
TO FREQUENT OCCURRENCE OF OXIDE)
[0062] Here the results are shown in Table 4 with comparing between
the copper alloy sample 35 (Example), for which there is not
performed any addition of any one element that is selected from Ag,
Co, Cr, Fe, Mn, P, Ti and Zr, and the copper alloy samples 36
through 43 (Examples) for which there is performed the addition of
any one of the above mentioned elements that is selected within the
range of the specification, and the copper alloy samples 44 through
51 (Comparative examples) for which there is performed the addition
of any one of the above mentioned elements that is selected with
the amount as less than the range of the specification. And hence
in accordance with the results with the comparison therebetween, it
is found out that there becomes to be improved the tensile strength
and the 0.2% yield strength due to a function caused by the
addition of the above selected any one of the elements in
accordance with the copper alloy samples 36 through 43 (for
instance, such as there is precipitated the chemical compound of
the above selected any one of the elements with Ni or with Si, or
the like). And in particular regarding the copper alloy samples 37,
38, 42 and 43, it is considered that there becomes able to be
controlled the characteristic of the growth of the crystalline
grains due to the addition of Co, Cr, Ti and Zr. As a result, it is
found out that there becomes to be further improved the bending
workability. Moreover, in the case where the amount of addition of
the above mentioned any one of the elements that is selected is
excessively lower on the contrary thereto, it is found out that it
is not able to obtain any one of the above mentioned improvements
and the advantages (refer to the copper alloy samples 44 through
51).
[0063] Further, in accordance with the copper alloy samples 52
through 59, it is designed to have individually the amount of
addition of the above mentioned any one of the elements that is
selected as excessively larger (as Reference examples). And hence
in accordance with such as the copper alloy sample 53 for instance,
it is not able to perform the hot working due to the occurrence of
the cracks thereon. Still further, in accordance with the copper
alloy samples 54, 58 and 59, it is not able to obtain any one of
samples due to the occurrence of the oxides to be generated as a
large amount at the period of the process of the casting.
Furthermore, in accordance with the copper alloy samples 52, 55, 56
and 57, there becomes to be decreased the electrical conductivity
as drastically or there becomes to be deteriorated the bending
workability, because there becomes to be increased the
precipitation due to the increasing of the amount of the
additions.
TABLE-US-00005 TABLE 5 RE- TEMPERATURE TEMPERATURE COPPER N
CRYSTALLIZATION RISING RETENTION FALLING ROLLING ALLOY INTERMEDIATE
CONCENTRATION TEMPERATURE RATE TIME RATE RATE SAMPLES SAMPLES (mass
%) (.degree. C.) (.degree. C./S) (S) (.degree. C./S) (%) 60 9 2.310
800 50 120 30 5 61 9 2.310 800 50 15 30 5 62 9 2.310 800 35 85 30 5
63 9 2.310 800 50 100 50 5 64 9 2.310 800 50 280 50 5 65 9 2.310
800 50 120 50 5 66 15 2.314 800 50 120 30 5 67 15 2.310 800 50 120
30 5 68 9 2.310 800 50 1 30 5 69 9 2.310 800 5 100 30 5 71 9 2.310
800 9 100 30 5 71 9 2.310 800 25 100 7 5 72 9 2.310 800 50 310 30 5
73 9 2.310 800 50 450 30 5 74 9 2.310 800 55 150 1 5 AVERAGE COPPER
TENSILE 0.2% YIELD ELECTRICAL CRYSTALLINE DEVIATION OF ALLOY
STRENGTH STRENGTH CONDUCTIVITY GRAIN GRAIN R/t R/t SAMPLES (MPa)
(MPa) (% IACS) DIAMETER (.mu.m) DIAMETER (.mu.m) (GW) (BW) 60 788
745 39 11.5 6.1 0.3 0.3 61 782 744 40 11.8 6.2 0.3 0.3 62 792 755
38 11.5 6.6 0.3 0.3 63 783 742 39 11.7 6.1 0.3 0.3 64 792 750 38
16.0 8.5 0.4 0.4 65 795 752 38 17.5 7.5 0.4 0.4 66 785 748 39 8.5
3.8 0.2 0.2 67 792 748 39 4.8 1.8 0.2 0.2 68 762 721 41 10.2 8.5
0.3 0.3 69 792 755 39 21.0 13.5 0.7 0.7 71 788 755 39 18.3 10.2 0.6
0.6 71 782 753 39 18.5 9.2 0.5 0.5 72 788 755 38 15.1 10.4 0.6 0.6
73 792 756 38 22.0 14.2 0.7 0.7 74 794 753 38 25.0 10.6 0.8 0.8
[0064] There are shown in Table 5 regarding the examples in the
case of changing the temperature rising rate at the period of the
process of treating with heat to be recrystallized, the end point
temperature (temperature to be recrystallized), the retention time
and the cooling (temperature falling) rate. And hence in accordance
with such as the copper alloy samples 69 through 74 (Comparative
examples) for instance, there are obtained the individual bending
workability as inferior due to such as the average crystalline
grain diameter becoming to be larger, or the like, because the
amount of time for the process becomes to be longer in the
temperature range at which the grain becomes to be grown. Moreover,
in accordance with the copper alloy sample 68 (Comparative
example), there are worsened the tensile strength and the 0.2%
yield strength, for which the retention time is excessively
shorter. Furthermore, the copper alloy samples 60 through 67
(Examples) on the contrary thereto, that there are performed the
process individually by making use of the temperature rising rate,
the retention time and the temperature falling rate within the
specification of the method for producing the copper alloy in
accordance with the present invention, it is found out that it
becomes able to obtain each of the characteristics of alloy for
each of Examples to be as excellent regarding each of the items of
the evaluation.
INDUSTRIAL APPLICABILITY
[0065] The copper alloy for an electrical and electronic device in
accordance with the present invention becomes to be applicable as
preferred to the usage for the electrical device and for the
electronic device, such as a lead frame, a connector, a terminal, a
relay, a switch, or the like. Moreover, the method for producing
the same in accordance with the present invention becomes to be
preferable as the method by which it becomes able to produce
further efficiently the above mentioned copper alloy for an
electrical and electronic device.
[0066] Thus, there is described as above regarding the present
invention in reference to the embodiment, however, the present
invention will not be limited to every detail of the description as
far as a particular designation, and it should be interpreted
widely without departing from the spirit and scope of the present
invention as disclosed in the attached claims.
[0067] Furthermore, the present invention claims the priority based
on Japanese Patent Application No. 2007-080266, filed in Japan on
the twenty-sixth day of March 2007, and on Japanese Patent
Application No. 2008-079256, that is filed in Japan on the
twenty-fifth day of March 2008, and the entire contents of which
are expressly incorporated herein by reference.
* * * * *