JP4981748B2 - Copper alloy for electrical and electronic equipment - Google Patents

Description

  The present invention relates to a copper alloy for electric / electronic devices applied to lead frames, connectors, terminal materials, etc. for electric / electronic devices, for example, connectors and terminal materials for automobiles, relays, switches, and the like.

Conventionally, as materials for electrical / electronic devices, copper-based materials such as phosphor bronze, red brass, brass, etc., which are excellent in electrical conductivity and thermal conductivity, have been widely used as materials for electric / electronic devices. In recent years, there has been an increasing demand for miniaturization, weight reduction, high functionality, and high-density mounting associated therewith, and various characteristics are required for copper-based materials applied thereto.
For example, as the heat generation amount of the CPU increases, the copper alloy used for the CPU socket or the like is required to have higher conductivity than before for heat removal. In addition, the use environment is becoming severe even for in-vehicle connectors, and for the purpose of improving heat dissipation, the copper alloy of the terminal material is required to have higher conductivity than before.
With the miniaturization of parts, the thinning of materials is progressing, and improvement in material strength is required. In applications such as relays, the demand for fatigue characteristics is increasing, and it is necessary to improve the strength. In addition, with the miniaturization of parts, the conditions for bending are becoming strict, and it is required to have excellent bending workability while having high strength. Furthermore, with the miniaturization of parts, the dimensional accuracy of parts is required more than before, and the amount of displacement of the spring material at the portion where contact pressure is applied is reduced. Since the settling of the material when used for a long time becomes a problem more than before, there is an increasing demand for stress relaxation resistance for the material. In automobiles and the like, since the use environment temperature is high, there is a high demand for stress relaxation resistance.

  These required properties have reached a point where they cannot be satisfied with commercially available mass-produced alloys such as phosphor bronze, red brass and brass. These alloys are improved in strength by dissolving Sn or Zn in Cu and adding cold working such as rolling or drawing to the alloy. In this method, the conductivity is not excellent, and a high strength material can be obtained by adding a high cold work rate (generally 50% or more), but it is known that the bending workability is remarkably deteriorated. ing. In general, this method is a combination of solid solution strengthening and work strengthening.

  As an alternative strengthening method, there is precipitation strengthening in which fine precipitates in the order of nanometers are formed and strengthened in the material. This method has the merit of improving the conductivity at the same time in addition to increasing the strength, and is therefore performed in many alloy systems. Among them, an alloy called Corson alloy, in which Ni and Si are added to Cu and Ni—Si compound is finely precipitated and strengthened, has a very high ability to strengthen among many precipitation-type alloys. Such commercial alloys (for example, CDA 70250, which is a CDA (Copper Development Association) registered alloy) are also used.

  In general, the following two important heat treatments can be incorporated into the manufacturing process of precipitation strengthened alloys. First, there is a so-called aging precipitation treatment in which Ni and Si are dissolved in a Cu matrix at a high temperature (usually 700 ° C. or more) called a solution treatment and a heat treatment at a temperature lower than the solution treatment temperature. The purpose is to precipitate Ni and Si dissolved at a high temperature as precipitates. This is a method of strengthening by using the difference in the amount of atoms in which Ni and Si are dissolved in Cu at a high temperature and a low temperature, and is a well-known technique in a method for producing a precipitation type alloy.

  Although the use amount of the Corson alloy is increasing, the electrical conductivity is insufficient for the high required characteristics described above. On the other hand, there is an example of a Cu—Ni—Co—Si alloy in which a part of Ni in the Corson alloy is replaced with Co (for example, Patent Document 1). This system is a precipitation hardened alloy of compounds such as Ni-Co-Si, Ni-Si, Co-Si, etc., and has a feature that the solid solution limit is smaller than that of the Corson system, and it has a high conductivity because it has fewer solid solution elements. There is an advantage that can be realized.

  On the other hand, the solution heat treatment temperature needs to be higher than that of the Cu—Ni—Si system due to the small solid solution limit. In addition, when the solution temperature cannot be increased, the amount of solid solution decreases at the time of solution treatment, so the amount of precipitation hardening decreases in the aging precipitation heat treatment, and the strength is compensated by work hardening with a relatively high work rate There is a need. As a result, bending is an important requirement due to the coarsening of crystal grains when the solution heat treatment temperature is high, and the increase of dislocation density in the material when work hardening with a relatively high processing rate is introduced. However, the required characteristics of copper materials, which are increasing in the fields of electronic devices and automobiles in recent years, cannot be satisfied.

In the Cu-Ni-Si system, there is an invention example in which the accumulation of crystal orientations is defined by the X-ray diffraction intensity of the plate surface in order to control bending workability (for example, Patent Document 2). However, the present invention is a technique by controlling the crystal grain size by adjusting the solution heat treatment conditions and reducing the work hardening amount. As described above, the solution heat treatment at a high temperature such as the Cu-Ni-Co-Si system. Is necessary in order to reduce the strength and bending workability.
JP 2005-532477 A Japanese Patent No. 3739214

  In view of the above problems, the object of the present invention is to provide excellent bending workability, excellent strength, and lead frames, connectors, terminal materials, etc. for electrical and electronic equipment, particularly connectors for automobiles It is to provide a copper alloy for electrical and electronic equipment suitable for use in electrical equipment, terminal materials, relays, switches, and the like.

  The present inventors have studied copper alloys suitable for electric / electronic component applications, and greatly improve bending workability, strength, conductivity, and stress relaxation resistance in Cu-Ni-Co-Si based copper alloys. Therefore, there is a correlation between the crystal orientation accumulation mode and the bending workability defined by the X-ray diffraction intensity of the material surface (for example, the surface of a plate-like or strip-like material, preferably the plate surface of the plate-like material). As a result, the present invention was made after intensive studies. In addition, in addition to finding an additive element that works to improve strength and stress relaxation resistance and an average crystal grain size that improves bending workability without losing conductivity in the present alloy system, the present invention It has been reached.

That is, the present invention
(1) Ni is 0.5 to 4.0 mass%, Co is 0.5 to 2.0 mass%, Si is 0.3 to 1.5 mass%, the balance is made of copper and inevitable impurities, and the material surface Diffraction intensity from the {111} plane is I {111}, diffraction intensity from the {200} plane is I {200}, diffraction intensity from the {220} plane is I {220}, diffraction from the {311} plane The intensity is I {311}, and the ratio of the diffraction intensity from the {200} plane among these diffraction intensities is R {200} = I {200} / (I {111} + I {200} + I {220} + I { 311}), R {200} is 0.3 or more, a copper alloy for electrical and electronic equipment,
(2) Ni is 0.5 to 4.0 mass%, Co is 0.5 to 2.0 mass%, Si is 0.3 to 1.5 mass%, and Ag, B, Cr, Fe, Hf, Contains one or more selected from Mg, Mn, P, Sn, Ti, Zn, and Zr in a total of 3 mass% or less, the balance is made of copper and inevitable impurities, and diffraction from the {111} plane on the material surface Intensity is I {111}, diffraction intensity from {200} plane is I {200}, diffraction intensity from {220} plane is I {220}, diffraction intensity from {311} plane is I {311}, these When the ratio of the diffraction intensity from the {200} plane in the diffraction intensity of R {200} = I {200} / (I {111} + I {200} + I {220} + I {311}) R {200} is 0.3 or more, electricity Copper alloy for electronic devices,
(3) The average crystal grain size is 20 μm or less, the copper alloy for electrical and electronic devices according to (1) or (2), and (4) 0.2% proof stress is 600 MPa or more. The electrical conductivity is 40% IACS or more, and the copper alloy for electrical / electronic equipment according to any one of (1) to (3) is provided.

  The copper alloy for electrical / electronic devices of the present invention is excellent in strength, bending workability, conductivity, and stress relaxation resistance. Due to the above characteristics, the copper alloy of the present invention is particularly suitable for use in lead frames, connectors, terminal materials, etc. for electrical and electronic equipment, particularly connectors, terminal materials, relays, switches, etc. for automobiles. Can do.

A preferred embodiment of the copper alloy of the present invention will be described in detail. In the following description, as an example, the copper alloy of the present invention will be described as having a shape such as a plate or a strip.
Ni, Co, and Si are formed for the purpose of improving the strength of the copper alloy by precipitation strengthening of Ni—Si, Co—Si, and Ni—Co—Si compounds by controlling the addition ratio of Ni + Co and Si. It is an element. The content of Ni is 0.5 to 4.0 mass%, preferably 1.0 to 3.0 mass%. The Co content is 0.5 to 2.0 mass%, preferably 0.7 to 1.7 mass%. The content of Si is 0.3 to 1.5 mass%, preferably 0.4 to 1.2 mass%. If these elements are added in an amount larger than this specified range, the electrical conductivity is lowered, and if they are less added, the strength is insufficient.

  In order to improve the bending workability, the present inventors investigated the cause of the occurrence of cracks in the bent part, and the cause is that plastic deformation has locally developed and locally reached the working limit. It was confirmed. As a countermeasure, the inventors discovered that bending workability can be improved by increasing the diffraction intensity from the {200} plane of the X-ray diffraction intensity on the plate surface. This is because there is an effect of suppressing the development of local deformation bands and shear bands that cause cracks when bending is performed with the {200} plane facing the surface direction. That is, it has the effect of dispersing deformation by becoming an orientation relationship in which more slipping systems of atoms can be active with respect to the stress direction of bending, and cracks are generated by suppressing the development of local deformation It is thought that it can be suppressed.

The diffraction intensity from the {111} plane on the plate surface is I {111}, the diffraction intensity from the {200} plane is I {200}, the diffraction intensity from the {220} plane is from I {220}, {311} plane. Is the diffraction intensity of I {311}, and the ratio of the diffraction intensity from the {200} plane in these diffraction intensities is R {200} = I {200} / (I {111} + I {200} + I {220} + I {311}), R {200} is 0.3 or more, preferably 0.4 or more. When R {200} becomes the above value, bending workability can be improved. In the present invention, the upper limit value of R {200} is not particularly limited, but is usually 0.98 or less.
In the present invention, the material surface (for example, plate surface) that defines R {200} refers to the surface of a plate or the like in the final state after completing a series of manufacturing steps.

  Examples of the method for raising and lowering the R {200} of the copper alloy according to the present invention include the following production conditions, but are not limited thereto. Before the final recrystallization heat treatment, I {200} is increased and R {200} is increased by introducing intermediate annealing to such an extent that the processed structure is not completely recrystallized and in addition to intermediate rolling. In addition, after the cold rolling and the recrystallization heat treatment are repeated one or more times after the hot rolling, the cold reworking and the final recrystallization heat treatment are performed, so that the diffraction intensity of I {111} or I {220} is increased. I {311} is increased and R {200} is decreased by performing the final recrystallization heat treatment after performing cold working at a high processing rate of 90% or more after hot rolling.

  Here, although an example of the process of achieving characteristic R {200} prescribed | regulated by this invention is shown, it is not limited to this. R {200} in the final state after the completion of all processes is largely governed by the crystal orientation developed in the recrystallization of the material that occurs during the final intermediate solution heat treatment in the manufacturing process. It is preferable to properly adjust the previous step. Here, the last intermediate solution heat treatment is a solution heat treatment performed last in the order of the steps in the solution heat treatment performed a plurality of times in the middle of one step and another step in all steps. Say. As a step before such a final intermediate solution heat treatment, cold rolling at a processing rate of 50% or more, followed by partial recrystallization or a recrystallized structure having an average crystal grain size of 5 μm or less. After the heat treatment as obtained, followed by cold rolling at a working rate of 50% or less, it is preferable to perform the final intermediate solution heat treatment. Examples of the heat treatment to be partially recrystallized or to obtain a recrystallized structure having an average crystal grain size of 5 μm or less include, for example, holding at 350 to 750 ° C. for 5 minutes to 10 hours, or higher temperatures of 600 to Examples thereof include holding at 850 ° C. for 5 seconds to 5 minutes, but are not limited thereto. A good recrystallized structure can be obtained by such heat treatment. Next, an example of a preferable process after the last intermediate solution heat treatment is shown. For example, after the final intermediate solution heat treatment, intermediate cold rolling, aging precipitation heat treatment, finish cold rolling, and temper annealing are performed to adjust strength, conductivity, and other characteristics according to the application. be able to. Here, it is preferable that the cold work rate (reduction rate) in the finish cold rolling after the aging precipitation heat treatment is 30% or less.

  Next, the effects of the additive elements of Ag, B, Cr, Fe, Hf, Mg, Mn, P, Sn, Ti, Zn, and Zr on this alloy will be described. If the total amount of these elements is too large, there may be a negative effect of reducing the electrical conductivity. In order to fully utilize the additive effect and not lower the electrical conductivity, the total amount is usually 3 mass% or less, preferably 0.01 mass% to 2.5 mass%, and more preferably 0.03 mass%. ~ 2 mass%.

  Mg, Sn, and Zn improve the stress relaxation resistance by adding to the Cu—Ni—Co—Si alloy. The stress relaxation resistance is further improved by the synergistic effect when added together than when they are added. In addition, the solder embrittlement is remarkably improved. These elements preferably have a total content of Mg, Sn, and Zn of more than 0.05 mass% and 2 mass% or less. If this total amount is too small, the effect may not appear, and if it is too large, the conductivity may be lowered.

  When Mn is added, hot workability is improved. It also improves strength. This is considered to be due to the effect of suppressing the segregation of solute atoms to the grain boundary during hot working and increasing the amount of solute atoms that are dissolved at this time, and thus increasing the precipitation hardening amount in the aging treatment.

  Cr, Fe, Ti, Zr, and Hf are finely precipitated as a compound or simple substance with Ni, Co, or Si, and contribute to precipitation hardening. Moreover, it precipitates with the magnitude | size of 50-500 nm as a compound, and there exists an effect which makes a crystal grain size fine by suppressing grain growth, and makes bending workability favorable.

  Further, by controlling the average crystal grain size to usually 20 μm or less, more preferably 10 μm or less, excellent bending workability is realized. In the present invention, the lower limit value of the average crystal grain size is not particularly limited, but is usually 3 μm or more. The crystal grain size was measured based on JIS H 0501 (cutting method).

  When the copper alloy of the present invention falls within the above prescribed range by adding the main component of Ni, Co, and Si and the {200} diffraction intensity of the X-ray diffraction intensity, By making the compounding amount of the auxiliary additive element and the average crystal grain size within the above preferred ranges, it is possible to achieve both excellent bending workability, strength and electrical conductivity. The tensile strength (0.2% proof stress) according to JIS Z2241 of the copper alloy of the present invention is preferably 600 MPa or more, more preferably 650 MPa or more, and the conductivity is preferably 40% IACS or more, more preferably 45% IACS or more. Here, although there is no restriction | limiting in particular in the upper limit of 0.2% yield strength, Usually, it is 1000 Mpa or less. Although there is no restriction | limiting in particular in the upper limit of electrical conductivity, Usually, it is 70% IACS or less. In addition, the stress relaxation rate measured under the condition of 150 ° C. × 1000 hours in accordance with the Japan Electronic Materials Industry Association Standard EMAS-3003 is preferably 40% or less, and more preferably 25% or less. Although there is no restriction | limiting in particular in the lower limit of the said stress relaxation rate, Usually, it is 3% or more.

  Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited thereto.

Example 1
The elements are blended so as to be the components shown in the table, and the remainder consisting of an alloy consisting of Cu and inevitable impurities is melted in a high-frequency melting furnace, and this is cast at a cooling rate of 0.1 to 100 ° C./second to make an ingot Got. This was held at 900 to 1020 ° C. for 3 minutes to 10 hours, then hot worked, then water quenched, and chamfered to remove oxide scale.
In the subsequent process, a copper alloy was manufactured by performing the processes of processes A-1 to B-4 described below.
The production process includes one or more solution heat treatments. Here, the processes are classified before and after the last solution heat treatment, and the process up to the intermediate solution treatment is defined as A process. The steps 1 to A-6 and the steps after the intermediate solution treatment are designated as step B, the steps B-1 to B-4, and combinations thereof, to obtain the copper alloys of the present invention example and the comparative example. A test material was used.

The contents of steps A-1 to A-6 and B-1 to B-4 are shown below.
Step A-1: Cold working with a cross-sectional reduction rate of 20% or more is performed, and solution heat treatment is performed at 800 to 1000 ° C. for 5 seconds to 30 minutes.
Step A-2: A heat treatment is performed at 350 to 750 ° C. for 5 minutes to 10 hours, a cold working with a cross-sectional reduction rate of 20% or more is performed, and a solution heat treatment is performed at 800 to 1000 ° C. for 5 seconds to 30 minutes. .
Step A-3: A cold working with a cross-sectional reduction rate of 20% or more is performed, a heat treatment is performed at 350 to 750 ° C. for 5 minutes to 10 hours, a cold working with a cross-sectional reduction rate of 5 to 50% is performed, and 800 A solution heat treatment is performed at ˜1000 ° C. for 5 seconds to 30 minutes.
Step A-4: Cold working with a cross-sectional reduction rate of 20% or more is performed, solution heat treatment is performed at 800 to 1000 ° C. for 5 seconds to 30 minutes, and heat treatment is performed at 350 to 750 ° C. for 5 minutes to 10 hours. Then, cold working with a cross-sectional reduction rate of 5 to 50% is performed, and solution heat treatment is performed at 800 to 1000 ° C. for 5 seconds to 30 minutes.
Step A-5: Cold work with a cross-section reduction rate of 5% or more, solution heat treatment at higher than 850 ° C. and 1000 ° C. or less for 5 seconds to 5 minutes, and cold work with a cross-section reduction rate of 5% or more And a solution heat treatment at 800 to 1000 ° C. for 5 seconds to 5 minutes.
Step A-6: Cold work with a cross-section reduction rate of 5% or more is performed, heat treatment is performed at 600 to 850 ° C. for 5 seconds to 5 minutes, cold work with a cross-section reduction rate of 5% or more is performed, and 800 to A solution heat treatment is performed at 1000 ° C. for 5 seconds to 5 minutes.
In the solution heat treatment, the heating rate up to the holding temperature was 5 to 500 ° C./sec, and the cooling rate after holding was 1 to 300 ° C./sec.

Step B-1: Heat treatment is performed at 400 to 700 ° C. for 5 minutes to 10 hours.
Process B-2: A heat treatment is performed at 400 to 700 ° C. for 5 minutes to 10 hours, a cold working with a cross-section reduction rate of 30% or less is performed, and a temper annealing is performed at 200 to 550 ° C. for 5 seconds to 10 hours. .
Step B-3: cold working with a cross-section reduction rate of 50% or less, heat treatment at 400 to 700 ° C. for 5 minutes to 10 hours, and cold working with a cross-section reduction rate of 30% or less, 200 to Temper annealing is performed at 550 ° C. for 5 seconds to 10 hours.
Step B-4: A heat treatment is performed at 400 to 700 ° C. for 5 minutes to 10 hours, a cold working with a cross-section reduction rate of 50% or less is performed, a heat treatment is performed at 400 to 700 ° C. for 5 minutes to 10 hours, Cold reduction with a reduction rate of 30% or less is performed, and temper annealing is performed at 200 to 550 ° C. for 5 seconds to 10 hours.

The following characteristics were investigated for each sample material. The results are also shown in the following table.
a. X-Ray Diffraction Intensity The diffraction intensity around one rotation axis was measured with respect to the sample by the reflection method. Copper was used for the target, and Kα X-rays were used. Measured under the conditions of a tube current of 20 mA and a tube voltage of 40 kV, and after removing the background of the diffraction intensity in the diffraction profile of each diffraction and the diffraction intensity, the integrated diffraction intensity obtained by combining Kα1 and Kα2 of each peak was obtained, From this, the value of R {200} was determined.
b. Bending workability W-bending was performed so that the axis of bending was parallel to the rolling direction at right angles to GW and BW, respectively, and the presence or absence of cracks in the bent portion was observed with a 50 × optical microscope to investigate the presence or absence of cracks. . The inner radius of the bent part was 0.2 mm. In the n = 5 field of view, no crack was observed, and a crack was observed in x.
c. Tensile strength (“YS” in the table below)
Three test pieces of JIS Z2201-13B cut out from the rolling parallel direction were measured according to JIS Z2241, and the average value (0.2% yield strength) was shown.
d. Conductivity (“EC” in the table below)
The specific resistance was measured by a four-terminal method in a constant temperature bath maintained at 20 ° C. (± 0.5 ° C.) to calculate the conductivity. In addition, the distance between terminals was 100 mm.
e. Stress relaxation rate (“SR” in the table below)
The measurement was performed under the conditions of 150 ° C. × 1000 hours in accordance with Japan Electronic Material Industries Association Standard EMAS-3003. An initial stress of 80% of the proof stress was applied by the cantilever method.
FIG. 1 is an explanatory diagram of a stress relaxation resistance test method, in which (a) shows a state before heat treatment and (b) shows a state after heat treatment. As shown in FIG. 1A, the position of the test piece 1 when an initial stress of 80% of the proof stress is applied to the test piece 1 held in a cantilever manner on the test stand 4 is a distance of δ ₀ from the reference. is there. This is held in a thermostatic bath at 150 ° C. for 1000 hours (heat treatment in the state of the test piece 1), and the position of the test piece 2 after removing the load is determined from the reference H _t as shown in FIG. Is the distance. 3 is a test piece when no stress is applied, and its position is a distance H ₁ from the reference. From this relationship, the stress relaxation rate (%) was calculated as (H _t −H ₁ ) / δ ₀ × 100. In the formula, δ ₀ is the distance from the reference to the test piece 1, H ₁ is the distance from the reference to the test piece 3, and H _t is the distance from the reference to the test piece 2.
f. Average grain size (referred to as “GS” in the table below)
It measured based on JISH0501 (cutting method).

  As shown in Table 1-1, Invention Example 1-1 to Invention Example 1-19 were all excellent in bending workability, yield strength, electrical conductivity, and stress relaxation resistance. However, as shown in Table 1-2, when the provisions of the present invention were not satisfied, at least one of the above characteristics was inferior. That is, since Comparative Example 1-1 did not contain Co, the conductivity was inferior. Since Comparative Example 1-2 had a low Ni content, the amount of precipitation decreased and the strength was poor. In Comparative Example 1-3, since the Si amount was low, the amount of precipitation decreased, and the strength and conductivity were inferior. Since Comparative Example 1-4 had a large amount of Ni, the conductivity was inferior. In Comparative Example 1-5, since the amount of Co was large, there were many crystallized substances and coarse precipitates, which became the starting point of cracks and had poor bending workability. Since Comparative Example 1-6 had a large amount of Si, the conductivity was inferior. Comparative Example 1-7, Comparative Example 1-8, and Comparative Example 1-9 had low R {200} and were inferior in bending workability.

  As shown in Table 2-1, Inventive Example 2-1 to Inventive Example 2-17 were all excellent in bending workability, yield strength, electrical conductivity, and stress relaxation resistance. However, as shown in Table 2-2, when the provisions of the present invention are not satisfied, at least one of the above characteristics is inferior. That is, Comparative Examples 2-1 and 2-2 were inferior in conductivity because of the large amount of other elements added. Moreover, Comparative Example 2-3, Comparative Example 2-4, and Comparative Example 2-5 had low R {200}, and the bending workability was inferior.

It is explanatory drawing of the stress relaxation test method in an Example, (a) is before heat processing, (b) is explanatory drawing which shows the state after heat processing.

Explanation of symbols

1 Test piece to which initial stress of 80% of proof stress was applied 2 Test piece after heat treatment in the state of test piece 1 after removing the load 3 Test piece when no stress was applied 4 Test stand δ Tested from ₀ standard distance from the distance H _t criterion from the distance H ₁ reference to pieces 1 to the test piece 3 to the test piece 2

Claims (4)

  Ni is 0.5 to 4.0 mass%, Co is 0.5 to 2.0 mass%, Si is 0.3 to 1.5 mass%, the balance is made of copper and inevitable impurities, and {111 } The diffraction intensity from the I plane is I {111}, the diffraction intensity from the {200} plane is I {200}, the diffraction intensity from the {220} plane is I {220}, and the diffraction intensity from the {311} plane is I. {311}, the ratio of the diffraction intensity from the {200} plane in these diffraction intensities is R {200} = I {200} / (I {111} + I {200} + I {220} + I {311}) In this case, R {200} is 0.3 or more, a copper alloy for electrical and electronic equipment.   Ni contains 0.5 to 4.0 mass%, Co contains 0.5 to 2.0 mass%, Si contains 0.3 to 1.5 mass%, and Ag, B, Cr, Fe, Hf, Mg, Mn , P, Sn, Ti, Zn, Zr, or a total of 3 mass% or less of one or more selected from the group consisting of copper and inevitable impurities, and the diffraction intensity from the {111} plane on the material surface is expressed as I The diffraction intensity from the {111}, {200} plane is I {200}, the diffraction intensity from the {220} plane is I {220}, the diffraction intensity from the {311} plane is I {311}, and these diffraction intensities R {200} where the ratio of the diffraction intensity from the {200} plane is R {200} = I {200} / (I {111} + I {200} + I {220} + I {311}) } Is 0.3 or more, electric / electronic Dexterity copper alloy.   The copper alloy for electrical and electronic equipment according to claim 1 or 2, wherein an average crystal grain size is 20 µm or less.   The copper alloy for electrical and electronic devices according to any one of claims 1 to 3, wherein the 0.2% proof stress is 600 MPa or more and the electrical conductivity is 40% IACS or more.

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