JP2001164328A - Copper alloy for connector and producing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a copper alloy combining various characteristics required for the material for electrical and electronic parts such as a connector in accordance wit the development of electronics, 1.e., a copper alloy for a connector excellent in strength, electrical conductivity, a Young's modulus, press formability, cost, or the like, and to provide a method for producing the same. SOLUTION: This copper alloy for a connector has a composition containing Zn and Sn in the ranges of 20 to 41 wt.% Zn and 0.1 to 4.0 wt.% Sn and also so as to satisfy the following inequality: 6.0<=0.25X+Y<=12, wherein X: the content (wt.%) of Zn, and Y: the content (wt.%) of Sn, and the balance Cu with inevitable impurities, provided that the content of S is controlled to <=30 ppm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copper alloy having strength and conductivity suitable for use as a material for electrical and electronic parts such as connectors and having a small Young's modulus, and a method for producing the same.

[0002]

2. Description of the Related Art With the recent development of electronics,
The electrical wiring of various machines is becoming more complicated and highly integrated, and accordingly, copper-clad products used for electrical and electronic components such as connectors are increasing. In addition, electrical and
Electronic components are required to be lightweight, highly reliable, and low in cost. Therefore, in order to satisfy these requirements, the copper alloy material for connectors is reduced in thickness and pressed into a complicated shape, so that it must have good strength, elasticity, conductivity, and press formability.

[0003] More specifically, the terminal has a strength not to buckle or deform when inserted or pulled out or bent, a strength for crimping and holding the electric wire, and therefore a tensile strength of 600 N / mm ² or more, preferably 700 N / mm ² or more. ^Two or more are preferred. Furthermore, the conductivity is 18% to suppress the generation of Joule heat due to energization.
IACS or higher is preferred. In addition, due to the miniaturization of the terminals, the requirements for press formability are becoming severer, and workability is required such that the ratio R / t of the radius (R) of the bent portion to the plate thickness (t) satisfies 1 or less.

Conventionally, it has been required that the connector be miniaturized and the material should have a large Young's modulus so that a large stress can be obtained with a small displacement. Operation standards, or management standards, such as variations in material thickness and residual stress, have become stricter.
Conversely, this has led to increased costs. Therefore, recently, there has been a demand for a design using a material having a small Young's modulus, a structure in which the displacement of the spring is made large, and a dimensional variation can be tolerated. Therefore, the Young's modulus is 115 kN / mm ² or less,
It is required to be preferably 110 kN / mm ² or less.

[0005] In addition to the above, the frequency of the maintenance of the mold also accounts for a large proportion of the cost, and has been getting closer. A major factor in mold maintenance is tool wear. When a material is pressed (punched or bent), tools such as punches, dies, and strippers wear, leading to burrs and dimensional defects in the processed material. At this time, the influence on the wear of the material itself is great. Accordingly, there is an increasing demand for improvement in mold wear on the material side.

Furthermore, it is necessary to have excellent corrosion resistance and stress corrosion cracking resistance, and since the female terminal is subjected to a thermal load, it must be excellent in stress relaxation resistance. Specifically, the life of stress corrosion cracking is desirably three times or more that of conventional brass, and the stress relaxation rate at 80 to 150 ° C. is less than half that of brass.

Hitherto, brass, phosphor bronze, and the like have been generally used as connector materials. Brass is used as a low-cost material, but its tensile strength is 60
Not exceed 0N / mm ^2, also corrosion resistance, stress corrosion cracking resistance,
Poor in stress relaxation resistance. Phosphor bronze has an excellent balance of strength, corrosion resistance, stress corrosion cracking resistance, and stress relaxation properties. However, for example, phosphor bronze for a spring has a small electric conductivity of 12% IACS, and is disadvantageous in cost. Therefore, many copper alloys have been researched, developed and proposed. However, many of the proposed copper alloys have a balance of properties such as strength, electric conductivity, and stress relaxation resistance by adding a trace amount of an additive element to copper, and have a Young's modulus of 120 to 135 kN / mm. ^It is a large value of ² ,
The cost was also high.

Here, the Young's modulus is 1 for both brass and phosphor bronze.
The low Young's modulus of 10 to 120 kN / mm ² satisfies the above design requirements, and these materials have recently been reviewed. Therefore, at a price close to that of brass, a tensile strength of 60
0 N / mm ² or more, conductivity 18% IACS or more, Young's modulus 115 kN / mm ² or less, preferably 110 kN / mm 2
Materials with ² or less are urgently desired.

Electrical and electronic parts such as connectors are made of Sn.
It is often plated, but in order to use it as a raw material, it is necessary to contain Sn as an alloy element. next,
Cutting, cutting or pressing waste requires degreasing, washing or the like in order to use it as a dissolving raw material due to the presence of oil for cutting, cutting or pressing. If used directly as a raw material without pre-treatment, the furnace wall may be damaged during the burning (oxidation) or evaporation of oil, or ingot blowholes may be generated due to the storage of hydrogen, which may lead to a decrease in yield and cost increase. Had become.

Further, in the conventional Sn-plated material, the manufacturing process of the base material and the surface treatment process such as Sn plating are performed independently of each other, so that cost reduction such as shortening of processes such as heat treatment is performed. There was room for Depending on the material of the base material, the presence / absence and thickness of the Cu base plating are studied. However, this is studied from the viewpoint of plating heat peeling, and the stress relaxation resistance, solderability, contact resistance,
The characteristics required for the connector terminal such as the spring property have not been comprehensively studied. Therefore, Cu
The study of the optimum film thickness of Sn and Sn was insufficient.

[0011]

SUMMARY OF THE INVENTION With the development of electronics, the present invention provides a copper alloy having the above-mentioned various characteristics required for materials for electrical and electronic parts such as connectors, that is, strength, conductivity, Young's modulus, press formability,
An object of the present invention is to provide a copper alloy for connectors excellent in cost and the like and a method for producing the same.

[0012]

SUMMARY OF THE INVENTION According to the present invention, the above-mentioned various characteristics required for materials for electrical and electronic parts such as connectors are reduced while adding a component which is cheaper than copper. An object of the present invention is to provide a copper alloy for a connector, which is excellent in strength, conductivity, Young's modulus, press formability, cost, and the like. Still another object of the present invention is to provide a production method capable of directly using, as a melting material, press waste of the present alloy in which Sn is surface-treated, and a production method for more advantageously obtaining a Sn surface-treated material of the present alloy.

That is, (1) Zn: 20 to 41 wt% Sn: contained in the range of 0.1 to 4.0 wt% and satisfy the following expression (1): 6.0 ≦ 0.25X + Y ≦ 12 (1) : Zn content (wt%), Y: Sn content (wt%), including Zn and Sn, with the balance being Cu and unavoidable impurities, provided that S is 30 ppm or less. alloy.

(2) Zn: 20 to 41 wt% Sn: contained in the range of 0.1 to 4.0 wt% and satisfy the following formula (1): 6.0 ≦ 0.25X + Y ≦ 12 (1) where X: Zn Content (wt%), Y: Sn content (wt%) including Zn and Sn, with the balance being Cu and unavoidable impurities, provided that S is 30 ppm or less and the area occupation ratio of the second phase is 10% or less. A copper alloy for a connector, comprising:

(3) Zn: 20 to 41 wt% Sn: contained in the range of 0.1 to 4.0 wt% and satisfy the following formula (1): 6.0 ≦ 0.25X + Y ≦ 12 (1) where X: Zn Content (wt%), Y: Sn content (wt%) including Zn and Sn, with the balance being Cu and unavoidable impurities, where S is 30 ppm or less. The area occupation ratio of the second phase is 10% or less. Further, the tensile strength is 600 N / mm ² or more, the conductivity is 18% IACS or more,
A copper alloy for a connector having a Young's modulus of 115 kN / mm ² or less.

(4) Zn: 20 to 41 wt% Sn: contained in the range of 0.1 to 4.0 wt% and satisfy the following formula (1): 6.0 ≦ 0.25X + Y ≦ 12 (1) where X: Zn (Wt%), Y: Sn content (wt%) including Zn and Sn, the balance being Cu and unavoidable impurities, Fe: 0.01 to 3 wt%, Ni: 0.
01-5 wt%, Co: 0.01-3 wt%, Ti0.01-3 wt%,
Mg: 0.01 to 2 wt%, Zr: 0.01 to 2 wt%, Ca: 0.01
-1 wt%, Si: 0.01-3 wt%, Mn: 0.01-5 wt%,
Cd: 0.01-3 wt%, Al: 0.01-5 wt%, Pb: 0.01
-3 wt%, Bi: 0.01-3 wt%, Be: 0.01-3 wt%,
Te: 0.01-1 wt%, Y: 0.01-3 wt%, La: 0.01-
3 wt%, Cr: 0.01-3 wt%, Ce: 0.01-3 wt%, A
u: 0.01 to 5 wt%, Ag: 0.01 to 5 wt%, P: 0.005 to
At least one element is contained in 0.5 wt%, and the total amount is 0.01 to 5 wt%, provided that S is 30 ppm or less, the area occupation ratio of the second phase is 10% or less, and the tensile strength is 600 N / mm ² or more, conductivity is 18% IACS or more,
A copper alloy for a connector, having a Young's modulus of 115 kN / mm ² or less.

(5) Cu underlayer: 0.3 on the surface of the metal material
The copper alloy for a connector according to any one of claims 1 to 4, wherein the copper alloy is subjected to a surface treatment of 2.0 to 2.0 m and Sn: 0.5 to 5.0 m.

(6) Zn: 20-41 wt%, Sn: 0.1-
Zn in the range of 4.0 wt% and satisfying the following equation (1):
Including Sn, 6.0 ≦ 0.25X + Y ≦ 12 (1) where, X: Zn content (wt%) Y: Sn content (wt%) The balance consists of Cu and unavoidable impurities. Fe: 0.01 to 3 wt%, Ni: 0.01 to 5 wt%, C
o: 0.01-3 wt%, Ti 0.01-3 wt%, Mg: 0.01-2
wt%, Zr: 0.01-2 wt%, Ca: 0.01-1 wt%, S
i: 0.01 to 3 wt%, Mn: 0.01 to 5 wt%, Cd: 0.01 to
3 wt%, Al: 0.01 to 5 wt%, Pb: 0.01 to 3 wt%, B
i: 0.01 to 3 wt%, Be: 0.01 to 3 wt%, Te: 0.01 to
1 wt%, Y: 0.01-3 wt%, La: 0.01-3 wt%, C
r: 0.01 to 3 wt%, Ce: 0.01 to 3 wt%, Au: 0.01 to
5 wt%, Ag: 0.01 to 5 wt%, P: 0.005 to 0.5 wt%, containing at least one or more elements, and the total amount is 0.01%.
A copper alloy material having a S content of 30 ppm or less, a heat treatment at a temperature of 300 to 750 ° C. for 1 to 360 minutes, followed by a cold working at a working rate of 15% or more to form a second phase. Has an area occupancy of 10% or less, a tensile strength of 600 N / mm ² or more, and a conductivity of 18% IACS or more,
A method for producing a copper alloy for a connector, wherein the Young's modulus is 115 kN / mm ² or less.

(7) Zn: 20-41 wt%, Sn: 0.1-
Zn in the range of 4.0 wt% and satisfying the following equation (1):
Including Sn, 6.0 ≦ 0.25X + Y ≦ 12 (1) where, X: Zn content (wt%) Y: Sn content (wt%) The balance consists of Cu and unavoidable impurities. Fe: 0.01 to 3 wt%, Ni: 0.01 to 5 wt%, C
o: 0.01-3 wt%, Ti 0.01-3 wt%, Mg: 0.01-2
wt%, Zr: 0.01-2 wt%, Ca: 0.01-1 wt%, S
i: 0.01 to 3 wt%, Mn: 0.01 to 5 wt%, Cd: 0.01 to
3 wt%, Al: 0.01 to 5 wt%, Pb: 0.01 to 3 wt%, B
i: 0.01 to 3 wt%, Be: 0.01 to 3 wt%, Te: 0.01 to
1 wt%, Y: 0.01-3 wt%, La: 0.01-3 wt%, C
r: 0.01 to 3 wt%, Ce: 0.01 to 3 wt%, Au: 0.01 to
5 wt%, Ag: 0.01 to 5 wt%, P: 0.005 to 0.5 wt%, containing at least one or more elements, and the total amount is 0.01%.
A copper alloy material having a S content of 30 ppm or less is subjected to a heat treatment at a temperature of 300 to 750 ° C. for 1 to 360 minutes, followed by cold working at a working rate of 15% or more. When the area ratio of the phase is 10% or less and the tensile strength is 60%
0 N / mm ² or more, conductivity of 18% IACS or more and Young's modulus of 115 kN / mm ² or less, and then a Cu underlayer: 0.3 to 2.0 μm and Sn: 0.5 to 5.0 μm on the surface of the copper alloy material.
A method for producing a copper alloy for a connector, comprising: performing a heat treatment at a temperature of 100 to 280 ° C. for 1 to 180 minutes after the surface treatment of m.

(8) In the above-mentioned manufacturing method, in the case where the above-mentioned alloy is press-punched scrap of a material obtained by subjecting the alloy of the invention to a surface treatment with Sn, the alloy or the inert gas atmosphere is used at a temperature of 300 to 600 ° C. for 0.5 to 24 hours. 8. The method for producing a copper alloy for a connector according to claim 7, wherein the copper alloy is melted after heat treatment in advance.

[0021]

Next, the contents of the present invention will be specifically described. First, the reasons for limiting the amounts of components in the copper alloy of the present invention will be described. Zn: By adding Zn, strength and resilience are improved and it is cheaper than Cu, so it is desirable to add a large amount, but if it exceeds 41 wt%, the area ratio of the second phase also exceeds 10%. The workability, corrosion resistance and stress corrosion cracking resistance are reduced. Further, the plating property and the solderability are reduced. On the other hand, if the content is less than 20 wt%, the strength and the spring property are insufficient, the Young's modulus becomes large, and when scrap made of Sn surface-treated is used as a raw material, hydrogen gas occlusion at the time of melting increases and blowholes of the ingot are generated. Easier to do. In addition, there is little inexpensive Zn, which is economically disadvantageous. Therefore, Zn may be in the range of 20 to 41 wt%. A more preferred range is 25 to 38% by weight.

Sn: A small amount of Sn has the effect of improving mechanical properties such as strength and elasticity. In addition, a small Young's modulus can be satisfied in the presence of Zn as compared with many copper alloys. Further, it is preferable that Sn is contained as an additive element from the viewpoint of reusing a material whose surface is treated with Sn such as Sn plating. However, when the Sn content increases, the electrical conductivity sharply decreases, and the hot workability also decreases. Conductivity 18%
In order to secure IACS, it must be in a range not exceeding 4.0 wt%. On the other hand, if the content is less than 0.1 wt%, the above effects cannot be expected. Therefore, Sn is 0.1 to
It may be in the range of 4.0 wt%.

The area ratio of the second phase is desirably 10% or less. Here, the second phase refers to all phases other than the first phase (so-called α phase) of a compound of Cu and Zn, for example, β phase, γ phase, or third and later additional elements described later, and Zn, Sn And a phase obtained by these compounds. If the total of these different phases exceeds 10%, the moldability will be extremely deteriorated and the Young's modulus will be affected at the same time. Therefore, the area ratio of the second phase is 1
0% or less, preferably 5% or less. However, it has been found advantageous to include a small amount of the second phase against mold wear. Such an effect is required to be 0.1% or more, more preferably 0.5% or more. Taking these into consideration, the preferred area ratio of the second phase is 0.5 to 5
%.

Further, if the range of the components is limited as described above, the area ratio of the second phase which precipitates beyond the solid solubility limit of Cu can be controlled, and is limited by the following formula (1). (FIG. 1. The composition range of the copper-based alloy in FIG. 1 is shaded), Zn and Sn are added to Cu to obtain a tensile strength of 600 N /
mm ² or more, conductivity 18% IACS or more, Young's modulus 1
15 kN / mm ² or less, further properties required as a connector material, in particular corrosion resistance, stress corrosion cracking resistance (more than 3 times cracking life brass one with ammonia vapors in), the stress relaxation property (80 It is possible to produce a copper base alloy for a connector that has a relaxation rate at 120 ° C. of less than half that of brass, comparable to that of phosphor bronze, and moldability (no cracking even in 90 ° W bending with R / t ≦ 1.0).

Expression (1) 6.0 ≦ 0.25X + Y ≦ 12 (1) where X: Zn content (wt%), Y: Sn content (wt%) In the expression (1), If the value is less than 6.0, the strength such as tensile strength decreases, and the desired Young's modulus cannot be obtained.
If it is larger, it will have an adverse effect such as a decrease in conductivity and moldability.

Further, it is desirable that S of the impurity is as small as possible. S, when contained in a small amount, significantly reduces the deformability in hot rolling. In particular, when using Sn-plated debris in a sulfuric acid bath or when S is taken in from oil such as a press, by controlling this value, cracking in hot rolling, particularly in the temperature range of 350 to 600 ° C. in hot rolling is performed. It can lead to prevention. To achieve such an effect, S should be 30
ppm or less, preferably 15 ppm or less is required.

Further, as a third additive element, Fe: 0.01
-3 wt%, Ni 0.01-5 wt%, Co: 0.01-3 wt%, T
i: 0.01 to 3 wt%, Mg: 0.01 to 2 wt%, Zr: 0.01 to
2 wt%, Ca: 0.01-1 wt%, Si: 0.01-3 wt%, M
n: 0.01 to 5 wt%, Cd: 0.01 to 3 wt%, Al: 0.01 to
5 wt%, Pb: 0.01-3 wt%, Bi: 0.01-3 wt%, B
e: 0.01 to 3 wt%, Te: 0.01 to 1 wt% Y: 0.01 to 3 wt%
%, La: 0.01 to 3 wt%, Cr: 0.01 to 3 wt%, Ca:
0.01-3 wt%, Au: 0.01-5 wt% Ag: 0.01-5 wt%
%, P: contains at least one or more elements of 0.005 to 0.5 wt%, and the total amount may contain 0.01 to 5 wt%.
These can improve the strength without significantly impairing the electrical conductivity, Young's modulus and moldability. If the content is out of the range of each element, the desired effect may not be obtained, or the moldability, conductivity, Young's modulus and cost may be disadvantageous.

Next, the reasons for limiting the manufacturing conditions according to the present invention will be described. In dissolving the press-punched scrap of the material obtained by surface-treating Sn in the alloy of the present invention as a raw material,
After a heat treatment at a temperature of 0 to 600 ° C. for 0.5 to 24 hours in the air or in an inert atmosphere, it is dissolved. At a temperature lower than 300 ° C., the combustion of the press oil adhering to the press waste is insufficient, and the moisture adsorbed during storage is insufficiently dried. ,
Hydrogen generated by the decomposition is absorbed into the molten metal and causes blowholes.

At a temperature exceeding 600 ° C., oxidation proceeds rapidly, causing dross. The dross increases the viscosity of the molten metal and lowers castability. Therefore, the heat treatment temperature is in the range of 300 to 600 ° C. If the time is less than 0.5 hours, the combustion of press oil and drying of water will not be enough,
If it exceeds 24 hours, Cu of the base material diffuses into the Sn surface treatment layer and is oxidized to form a Cu—Sn—O-based oxide, which causes dross, and is not economical. Accordingly, the heat treatment time is in the range of 0.5 to 24 hours. Although the atmosphere is sufficient in the air, it is preferable to seal with an inert gas from the viewpoint of preventing oxidation. However, if the temperature becomes high in the reducing gas, it is disadvantageous due to absorption and diffusion of hydrogen due to decomposition of water.

Further, after subjecting the copper alloy material to a heat treatment at a temperature of 350 to 750 ° C. for 1 to 360 minutes, a Cu underlayer of 0.3 to 2.0 μm,
After a surface treatment of Sn 0.5-5.0 μm, 100-28
When the heat treatment is performed at a temperature of 0 ° C. for 1 to 180 minutes, the characteristics as a connector material can be further improved.

In the annealing before the final cold working, the press formability is improved by controlling the crystal grain size to 5 to 20 μm, but the processing temperature at this time is preferably 300 to 750 ° C.
If the temperature is lower than 300 ° C., the temperature required for recrystallization is too low, and the processing time becomes longer, which is not economical. The time is preferably from 1 to 360 minutes. If the treatment time is too short, the control of the crystal grains by recrystallization is not sufficient, and if the treatment time is too long, the growth and coarsening of the crystal grains are likely to occur, and it is economically disadvantageous. Further, the final cold working ratio is preferably 15% or more. If it is less than 15%, improvement in strength, hardness and the like by work hardening is not sufficient. However, if the working ratio is too large, the workability decreases, so the preferred range is 15 to 80%, more preferably 20 to 60%.

The material thus obtained was treated with a Cu underlayer of 0.3 to 2.0 μm and a Sn surface treatment of 0.3 to 2.0 μm.
Apply 5 to 5.0 μm. When the Cu underlayer is less than 0.3 μm, the effect of preventing the increase in contact resistance and the decrease in solderability due to the diffusion and oxidation of Zn in the alloy to the surface treatment layer and the surface is small, and the effect is more than 2.0 μm. It becomes saturated and less economical. However, Cu base plating is pure Cu
Not limited to this, a copper alloy such as Cu-Fe or Cu-Ni may be used.

If the Sn surface treatment layer is less than 0.5 μm, the corrosion resistance, particularly hydrogen sulfide resistance, is insufficient, and if it exceeds 5.0 μm, the effect is saturated and it is economically disadvantageous. further,
If these surface treatments are performed by electroplating, it is preferable in terms of uniformity of film thickness and economy. After the surface treatment, a reflow treatment may be performed to give gloss. This processing is also effective for whisker countermeasures.

This surface treatment material is heat-treated at a temperature of 100 to 280 ° C. for 1 to 180 minutes. By this heat treatment, the spring limit value of the material, the stress relaxation resistance, and the whisker countermeasures can be realized. If the temperature is lower than 100 ° C., such an effect is not sufficient. If the temperature is higher than 280 ° C., the contact resistance, the solderability and the workability are reduced due to diffusion and oxidation. Further, if the heat treatment time is less than 1 minute, the effect is not sufficient, and if the heat treatment time exceeds 180 minutes, the above-mentioned property deterioration due to diffusion and oxidation occurs, and it is not economical. Next, embodiments of the present invention will be described with reference to examples.

[0035]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Example 1 Table 1 shows copper alloy Nos. Having chemical components (wt%). 1 to 11 were melted using a high-frequency induction melting furnace, and 40 × 40 × 150
(Mm). However, the atmosphere at the time of melting and casting was an Ar gas atmosphere, and water cooling was performed immediately after casting. Here, No. The alloy No. 11 was subjected to rapid melting casting without treating the oil of the Sn plating waste in the raw material. Thereafter, each ingot was subjected to hot rolling, and then cold rolling and annealing were repeated to a thickness of 0.50 mm. Then, after a heat-treated material at a temperature of 450 ° C. for 60 minutes, water quenching was performed, and further, pickling was performed. The heat-treated material obtained as described above was cold-rolled to a thickness of 0.25 mm to obtain a test material.

Using the test materials thus obtained, Vickers hardness, tensile strength, Young's modulus and conductivity were measured. The test method was JIS-Z-224.
4, according to JIS-Z-2241 and JIS-H-0505. The bending workability was determined by the 90 ° W bending test (CES-
M-0002-6, R = 0.2 mm, R / t = 0.8, rolling direction and vertical direction). Were evaluated as x marks.

[0037]

[Table 1]

From the results shown in Table 1, it is found that N
o. Copper alloys Nos. 1 to 8 have an excellent balance of tensile strength, Young's modulus and electrical conductivity, and also have good bending workability. Therefore, it is a copper alloy having very excellent properties as an electric / electronic material such as a connector. No. In all of the alloys 1 to 8, the area ratio of the second phase was within 5%. In order to examine the area ratio of the second phase, the plate surface was polished and the structure was observed after etching.

On the other hand, when the Zn and Sn contents are (1)
A smaller No. defined by the equation No. 9 is inferior in tensile strength and Young's modulus and has a Zn and Sn content larger than that specified by a set. In No. 10, the area ratio of the second phase exceeds 10%, and the bending workability is poor. Even when the contents of Zn and Sn are within the range defined by the formula (1), no. In No. 11, a crack was formed during hot rolling, and it could not be manufactured with a good yield to the final thickness due to the subsequent cold working.

Example 2 Inventive alloy No. 1 shown in Table 1 of Example 1. 1 and commercially available brass (C2600-EH) and phosphor bronze (C519)
For 1-EH), hardness, tensile strength, bending workability, Young's modulus, conductivity, and stress corrosion cracking life were measured by test.
The test for hardness, tensile strength, Young's modulus, and conductivity was performed in the same manner as in Example 1. The stress corrosion cracking time was determined by applying a bending stress of about 400 N / mm ^{2 to} the sample and applying 12.5% ammonia. Exposure time in the desiccator containing water and the time when cracks occurred.

From the results shown in Table 2, the copper alloy of the present invention was
It can be seen that the strength, Young's modulus, bending workability, and stress corrosion cracking resistance are improved as compared with brass, which is a conventional electrical and electronic material for connectors and the like. Excellent in strength, bending workability, Young's modulus, and conductivity as compared with phosphor bronze. Furthermore, it can be said that the cost is excellent in terms of the components and the production process. Therefore, the copper-based alloy of the present invention is a conventional brass,
It can be said that it is sufficiently superior to phosphor bronze.

[0042]

[Table 2]

Example 3 After producing the alloy strips of the present invention shown in Table 3, a Cu base plating was performed.
After 0.5 μm and 1.1 μm of Sn plating, a material punched out by press was prepared as a raw material for melting casting.
The target composition in the casting is shown in Table 3. Press scrap as a raw material for melting was about 1 t, and the balance was adjusted with electric Cu and Zn to obtain six ingots of about 2 t. The components of the obtained ingot were almost the same as in Table 3.

Here, the three pieces were prepared by pressing 450 parts of raw material press waste.
Heated at 0 ° C for 3 hours in air. The other three did nothing. This was rapidly melted to cast a 2t ingot, and hot rolling, cold rolling and annealing were repeated to finish to 0.25 mm. Inspect the full length of the material obtained in this way,
The number of defects caused by ingot broholes was counted. (Table 4) Table 4 shows that the heat-treated press waste obtained by the method of the present invention was excellent without defects. On the other hand, those not subjected to the heat treatment have defects, indicating that there is a problem in the yield.

[0045]

[Table 3]

[0046]

[Table 4]

The alloy No. 1 of the present invention obtained in Example 1 was used.
1 was coated with 0.5 μm of Cu base plating and 1.1 μm of Sn plating, and then heat-treated at 190 ° C. for 60 minutes. Table 5 compares the properties of this material and those that were not heat-treated after plating. However, the stress relaxation rate is
The test piece was bent in an arch shape so that the stress at the center of the test piece became 400 N / mm ² , and the bending after holding at a temperature of 150 ° C. for 500 hours was calculated as a stress relaxation rate by the following equation. Stress relaxation rate (%) = [(L ₁ −L ₂ ) / (L ₁ −L)
₀ )] × 100 where L ₀ : length of jig (mm) L ₁ : sample length at start (mm) L ₂ : horizontal distance between sample ends after processing (mm)

[0048]

[Table 5]

From Table 5, it was found that the material heat-treated by the method of the present invention after the plating treatment had better characteristics than the material not heat-treated, and was suitable for connectors. In addition, the conventional alloy (brass 1 class comparative material)
C2600 EH, Phosphor bronze type 2 Comparative material C5191
H alloys in Table 2) had a stress relaxation rate of 56.5
% And 22.1%, which shows that the alloy of the present invention and the method of the present invention have excellent stress relaxation resistance.

The alloy No. of the present invention obtained in Example 1 in Table 1 was obtained. No. 5 and Comparative Alloy No. 5 9 was prepared. In order to examine the area ratio of the second phase, the plate surface was polished and the structure was observed after etching. As a result, the alloy No. 1 of the present invention. The area ratio of the second phase of Comparative Alloy No. 5 was 3%. 9 could not confirm the second phase. (Α single phase). The area ratio may be determined by the dot method as described above, or may be determined by another method (for example, an image analysis method using a computer). When the clearance was set to 8% of the plate thickness using a carbide punch and a tool steel die, the burrs after 1 million shots of press punching were examined in the rolling direction and the perpendicular direction. No burrs were observed in Comparative Alloy No. 5; The portion parallel to the rolling direction of No. 9 had burrs as large as 15 μm. From the above, No. 1 according to the present invention. 5
It can be seen that alloy No. is also excellent in mold wear.

[0051]

As is clear from the above examples, the copper-based alloy according to the present invention or the material obtained by the method of the present invention has strength, conductivity, and conductivity which are lower than those of conventional brass and phosphor bronze. Excellent in environmental resistance, heat resistance, stress relaxation resistance, mold abrasion, etc., including balance of Young's modulus and moldability, making it an ideal electrical and electronic material for inexpensive connectors such as brass and phosphor bronze. .

[Brief description of the drawings]

FIG. 1 illustrates 6.0 ≦ 0.25X + Y ≦ 12 according to the present invention.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C22F 1/00 694 C22F 1/00 694A

Claims (8)

[Claims] 1. Zn: 20-41 wt%, Sn: 0.1-4.
Zn, S in the range of 0 wt% and satisfying the following expression (1):
6.0 ≦ 0.25X + Y ≦ 12 (1) where X: Zn content (wt%) Y: Sn content (wt%) The balance is made of Cu and unavoidable impurities. 3
A copper alloy for a connector characterized by being at most 0 ppm. 2. Zn: 20-41 wt%, Sn: 0.1-4.
Zn, S in the range of 0 wt% and satisfying the following expression (1):
6.0 ≦ 0.25X + Y ≦ 12 (1) where X: Zn content (wt%) Y: Sn content (wt%) The balance is made of Cu and unavoidable impurities. 3
A copper alloy for a connector, wherein the copper alloy content is 0 ppm or less and the area occupation ratio of the second phase is 10% or less. 3. Zn: 20-41 wt%, Sn: 0.1-4.
Zn, S in the range of 0 wt% and satisfying the following expression (1):
6.0 ≦ 0.25X + Y ≦ 12 (1) where X: Zn content (wt%) Y: Sn content (wt%) The balance is made of Cu and unavoidable impurities. 3
0 ppm or less, the area occupation ratio of the second phase is 10% or less, the tensile strength is 600 N / mm ² or more, and the conductivity is 1 or less.
A copper alloy for a connector, characterized in that it has an IACS of 8% or more and a Young's modulus of 115 kN / mm ² or less. 4. Zn: 20-41 wt%, Sn: 0.1-4.
Zn, S in the range of 0 wt% and satisfying the following expression (1):
6.0 ≦ 0.25X + Y ≦ 12 (1) where X: Zn content (wt%) Y: Sn content (wt%) The balance consists of Cu and unavoidable impurities. 0.
01-3 wt%, Ni: 0.01-5 wt%, Co: 0.01-3 wt%
%, Ti: 0.01 to 3 wt%, Mg: 0.01 to 2 wt%, Zr: 0.
01-2wt%, Ca: 0.01-1wt%, Si: 0.01-3wt
%, Mn: 0.01 to 5 wt%, Cd: 0.01 to 3 wt%, Al:
0.01-5 wt%, Pb: 0.01-3 wt%, Bi: 0.01-3 wt%
%, Be: 0.01 to 3 wt%, Te: 0.01 to 1 wt%, Y: 0.
01-3wt%, La: 0.01-3wt%, Cr: 0.01-3wt
%, Ce: 0.01 to 3 wt%, Au: 0.01 to 5 wt%, Ag:
0.01 to 5 wt%, P: 0.005 to 0.5 wt%, containing at least one or more elements, the total amount of which is 0.01 to 5 wt%, provided that S is 30 ppm or less, and the area occupation ratio of the second phase is 10% or less. And a tensile strength of at least 600 N / mm ² , a conductivity of at least 18% IACS, and a Young's modulus of 115 kN / mm ^2.
A copper alloy for connectors characterized by the following. 5. The method according to claim 1, wherein the surface of the metal material has a Cu underlayer: 0.3 to
The copper alloy for a connector according to any one of claims 1 to 4, wherein a surface treatment of 2.0 m and Sn: 0.5 to 5.0 m is performed. 6. Zn: 20-41 wt%, Sn: 0.1-4.
Zn, S in the range of 0 wt% and satisfying the following expression (1):
6.0 ≦ 0.25X + Y ≦ 12 (1) where, X: Zn content (wt%) Y: Sn content (wt%) The balance consists of Cu and unavoidable impurities. Fe: 0.01 to 3 wt%, Ni: 0.01 to 5 wt%, C
o: 0.01-3 wt%, Ti 0.01-3 wt%, Mg: 0.01-2
wt%, Zr: 0.01-2 wt%, Ca: 0.01-1 wt%, S
i: 0.01 to 3 wt%, Mn: 0.01 to 5 wt%, Cd: 0.01 to
3 wt%, Al: 0.01 to 5 wt%, Pb: 0.01 to 3 wt%, B
i: 0.01 to 3 wt%, Be: 0.01 to 3 wt%, Te: 0.01 to
1 wt%, Y: 0.01-3 wt%, La: 0.01-3 wt%, C
r: 0.01 to 3 wt%, Ce: 0.01 to 3 wt%, Au: 0.01 to
5 wt%, Ag: 0.01 to 5 wt%, P: 0.005 to 0.5 wt%, containing at least one or more elements, and the total amount is 0.01%.
A copper alloy material having a S content of 30 ppm or less, a heat treatment at a temperature of 300 to 750 ° C. for 1 to 360 minutes, followed by a cold working at a working rate of 15% or more to form a second phase. Has an area occupancy of 10% or less, a tensile strength of 600 N / mm ² or more, and a conductivity of 18% IACS or more,
A method for producing a copper alloy for a connector, wherein the Young's modulus is 115 kN / mm ² or less. 7. Zn: 20-41 wt%, Sn: 0.1-4.
Zn, S in the range of 0 wt% and satisfying the following expression (1):
6.0 ≦ 0.25X + Y ≦ 12 (1) where, X: Zn content (wt%) Y: Sn content (wt%) The balance consists of Cu and unavoidable impurities. Fe: 0.01 to 3 wt%, Ni: 0.01 to 5 wt%, C
o: 0.01-3 wt%, Ti 0.01-3 wt%, Mg: 0.01-2
wt%, Zr: 0.01-2 wt%, Ca: 0.01-1 wt%, S
i: 0.01 to 3 wt%, Mn: 0.01 to 5 wt%, Cd: 0.01 to
3 wt%, Al: 0.01 to 5 wt%, Pb: 0.01 to 3 wt%, B
i: 0.01 to 3 wt%, Be: 0.01 to 3 wt%, Te: 0.01 to
1 wt%, Y: 0.01-3 wt%, La: 0.01-3 wt%, C
r: 0.01 to 3 wt%, Ce: 0.01 to 3 wt%, Au: 0.01 to
5 wt%, Ag: 0.01 to 5 wt%, P: 0.005 to 0.5 wt%, containing at least one or more elements, and the total amount is 0.01%.
A copper alloy material having a S content of 30 ppm or less is subjected to a heat treatment at a temperature of 300 to 750 ° C. for 1 to 360 minutes, followed by cold working at a working rate of 15% or more. When the area ratio of the phase is 10% or less and the tensile strength is 60%
0 N / mm ² or more, conductivity of 18% IACS or more and Young's modulus of 115 kN / mm ² or less, and then a Cu underlayer: 0.3 to 2.0 μm and Sn: 0.5 to 5.0 μm on the surface of the copper alloy material.
A method for producing a copper alloy for a connector, comprising: performing a heat treatment at a temperature of 100 to 280 ° C. for 1 to 180 minutes after the surface treatment of m. 8. The method according to claim 1, wherein the alloy of the invention is
8. The method according to claim 7, wherein in the case of using as a raw material a stamping waste of a material whose n has been surface-treated, the material is heat-treated at a temperature of 300 to 600 ° C. for 0.5 to 24 hours in the air or in an inert gas atmosphere and then melted. Manufacturing method of copper alloy.