KR20160090871A - Copper alloy plate having excellent electroconductivity, moldability, and stress relaxation properties - Google Patents

Abstract

A copper alloy plate having high strength, high conductivity and excellent stress relaxation characteristics, and an electronic component for large current and a heat dissipation electronic component using the copper alloy plate. At least one of Ni and Co in a total amount of 0.8 to 5.0 mass% and Si in an amount of 0.2 to 1.5 mass%, the balance of copper and inevitable impurities, a 0.2% proof stress of 500 MPa or more and a conductivity of 30% IACS or more ₍₂₀₀₎ / I _{0 (200)} ≥ 1.0, and a residual stress occurring in a direction parallel to the rolling direction with respect to a (113) plane obtained by X-ray diffractometry is 200 MPa or less. Alloy plate. (Where I _(hkl) and Io _(hkl) are the diffraction integral intensities of (hkl) planes obtained by X-ray diffraction on the copper alloy plate surface and copper powder, respectively).

Description

TECHNICAL FIELD [0001] The present invention relates to a copper alloy plate having excellent conductivity, molding processability and stress relaxation property,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copper alloy plate and an electronic component for exclusive use or heat dissipation and more particularly to an electronic component such as a terminal, a connector, a relay, a switch, a socket, a bus bar, a lead frame, A copper alloy plate used as a material of the copper alloy plate, and an electronic part using the copper alloy plate. Among them, a copper alloy plate and a copper alloy plate which are suitable for the use of electronic components for large current such as connectors and terminals for large currents used in electric vehicles and hybrid cars, and for applications of heat dissipation electronic components such as liquid crystal frames used in smart phones and tablet PCs And an electronic component using the copper alloy plate.

BACKGROUND OF THE INVENTION [0002] Electrical and electronic devices and automobiles are equipped with components for transmitting electricity or heat such as terminals, connectors, switches, sockets, relays, bus bars, lead frames and heat sinks. Copper alloys are used for these components. Here, the electrical conductivity and the thermal conductivity are in a proportional relationship.

In recent years, with the miniaturization of electronic components, the cross-sectional area of the copper alloy in the conductive portion tends to be small. As the cross-sectional area becomes smaller, the heat generated from the copper alloy when energized increases. Also, in electronic parts used in electric vehicles and hybrid electric vehicles in which growth is remarkable, there are parts in which a considerably high current flows, such as connectors of a battery part, and heat generation of the copper alloy in service becomes a problem. If the heat generation is excessive, the copper alloy is exposed to a high temperature environment.

In the electrical contacts of electronic parts such as connectors, the copper alloy sheet is warped, and the contact force at the contacts is obtained by the stress generated by the warping. When the copper alloy to which the warp is imparted is kept at a high temperature for a long time, the stress or contact force is lowered due to the stress relaxation phenomenon, and the contact electrical resistance is increased. To cope with this problem, a copper alloy is required to have better conductivity so as to reduce the calorific value, and furthermore, a stress relaxation property is required so that the contact force is not lowered even when heat is generated.

On the other hand, for example, a heat dissipation component called a liquid crystal frame is used for a liquid crystal of a smartphone or a tablet PC. Even in such a copper alloy plate for heat radiation use, when the stress relaxation property is increased, the creep deformation of the heat sink due to external force is suppressed, and the protection against liquid crystal parts and IC chips arranged around the heat sink is improved You can expect.

The copper alloy sheet is subjected to a forming process such as a bending process and a drawing process to form electronic parts for exclusive use or heat dissipation. However, with miniaturization and high functionality of the parts, more excellent molding processability is required for the copper alloy sheet have.

A Korson alloy is known as a copper alloy having high conductivity, high strength, and relatively good stress relaxation characteristics and molding processability. Korson alloy is an alloy in which an intermetallic compound such as Ni-Si, Co-Si, or Ni-Co-Si is precipitated in a Cu matrix.

Recent researches on the Korson alloy are mainly aimed at improving the bending workability, and techniques for developing the {001} < 100 > orientation (cube orientation) have been proposed as a countermeasure therefor. For example, in Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2006-283059), the area ratio of the Cube orientation is controlled to 50% or more to improve the bending workability. In Patent Document 2 (JP-A-2010-275622), the X-ray diffraction intensity of (200) (equivalent to {001}) is controlled to be equal to or higher than the X-ray diffraction intensity of the copper powder standard sample, . In Patent Document 3 (Japanese Unexamined Patent Publication No. 2011-17072), the area ratio of the Cube orientation is controlled to 5 to 60%, the area ratio of the Brass orientation and the Copper orientation are all controlled to 20% or less and the bending workability . In Patent Document 4 (Japanese Patent No. 4857395), the area ratio of the Cube orientation is controlled to 10 to 80% at the central portion in the plate thickness direction, and both the area ratio of the Brass orientation and the copper orientation are all 20% So as to improve the notch bending property. In Patent Document 5 (WO2011 / 068121), W0 and W4 are the Cube bearing areal ratios at 1/4 of the total surface layer depth position, W0 / W4 is 0.8 to 1.5, W0 is 5 To 48% and further adjusting the average crystal grain size to 12 to 100 占 퐉, thereby improving the 180 ° contact bending property. In Patent Document 6 (WO2011 / 068134), the Young's modulus is adjusted to 110 ㎬ or less and the bending flexural modulus to 105 ㎬ or less by controlling the area ratio of the (100) face facing the rolling direction to 30% or more.

Japanese Patent Application Laid-Open No. 2006-283059 Japanese Laid-Open Patent Publication No. 2010-275622 Japanese Laid-Open Patent Publication No. 2011-17072 Japanese Patent No. 4857395 International Publication WO2011 / 068121 International Publication WO2011 / 068134

However, although the Korson alloy has a relatively good stress relaxation property, the level of the stress relaxation property is not necessarily sufficient for the use of a component that flows a large current or the use of a component that dissipates large heat. Particularly, a Korson alloy having good stress relaxation characteristics and molding processability has not been reported so far.

It is therefore an object of the present invention to provide a copper alloy plate having high strength, high electrical conductivity, excellent molding processability, and excellent stress relaxation characteristics, and more specifically, to provide a copper alloy plate having improved moldability and stress relaxation characteristics And the like. It is also an object of the present invention to provide an electronic component suitable for a large current application or a heat radiation application.

As a result of intensive investigations, the inventor of the present invention has found that when a Corsius alloy having a high strength and a high conductivity is grown on the surface of a Corson alloy and the residual stress on the surface is adjusted to a predetermined range, At the same time, it was understood that it improved.

The present invention, which is based on the above findings,

(1) A steel sheet comprising (A) at least one of Ni and Co in a total amount of 0.8 to 5.0 mass% and Si in an amount of 0.2 to 1.5 mass%, the balance being copper and inevitable impurities, ₍₂₀₀₎ / I _{0 (200)} ? 1.0, and the residual stress occurring in the direction parallel to the rolling direction with respect to the (113) plane determined by the X-ray diffraction method is 200 MPa or less Made of copper alloy. (Where I _(hkl) and Io _(hkl) are the diffraction integral intensities of the (hkl) plane obtained by X-ray diffraction on the surface of the copper alloy plate and the copper powder, respectively)

(2) A copper alloy sheet according to (1), characterized by containing at least 3.0% by mass of at least one of Sn, Zn, Mg, Fe, Ti, Zr, Cr, Al, P, Mn, .

(3) An electronic component for a large current using the copper alloy plate according to (1) or (2).

(4) A heat-dissipating electronic component using the copper alloy plate according to (1) or (2).

.

According to the present invention, it is possible to provide a copper alloy plate having high strength, high electrical conductivity, excellent molding processability, and excellent stress relaxation characteristics, and an electronic part suitable for use in a large current or heat radiation. This copper alloy plate can be preferably used as a material for an electronic part such as a terminal, a connector, a switch, a socket, a relay, a bus bar, a lead frame and a heat sink. Particularly, And is useful as a material for an electronic component.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a graph showing the relationship between an annealing temperature and a tensile strength when an alloy according to the present invention is annealed at various temperatures. FIG.
2 is a view for explaining the principle of measurement of residual stress.
3 is a view for explaining the principle of measurement of the stress relaxation rate.
4 is a view for explaining the principle of measurement of the stress relaxation rate.

Hereinafter, the present invention will be described.

(Addition amount of Ni, Co and Si)

A copper alloy plate used as a material for a part for energizing a large current or a part for dissipating a large amount of heat needs a conductivity of 30% IACS or more and a 0.2% proof stress of 500 MPa or more. Therefore, Ni and / or Co is added to the copper alloy sheet of the present invention, and further Si is added. Ni, Co, and Si are precipitated as intermetallic compounds such as Ni-Si, Co-Si, and Ni-Co-Si by appropriate aging treatment. The strength improves by the action of the precipitate, and the Ni, Co, and Si solidified in the Cu matrix by the precipitation decrease, so that the conductivity is improved.

When the total amount of Ni and Co is less than 0.8 mass% or Si is less than 0.2 mass%, it becomes difficult to obtain a 0.2% proof stress of 500 MPa or more. When the total amount of Ni and Co exceeds 5.0 mass%, or when Si exceeds 1.5 mass%, it becomes difficult to obtain a conductivity of 30% IACS or more. Therefore, in the corundum alloy according to the present invention, the addition amount of at least one of Ni and Co is set to 0.8 to 5.0 mass% in total, and the addition amount of Si is set to 0.2 to 1.5 mass%. The addition amount of at least one of Ni and Co is more preferably 1.0 to 4.0 mass%, and the addition amount of Si is more preferably 0.25 to 0.90 mass%.

(Other added elements)

The corson alloy may contain at least one of Sn, Zn, Mg, Fe, Ti, Zr, Cr, Al, P, Mn, B and Ag in order to improve strength and heat resistance. However, if the added amount is too large, the conductivity may be lowered to less than 30% IACS or the composition of the alloy may be deteriorated. Therefore, the total amount is preferably 3.0% by mass or less, more preferably 2.5% by mass or less . In order to obtain the effect of addition, it is preferable that the addition amount is 0.001 mass% or more in total amount.

(Crystal orientation)

In the present invention,? / 2? Measurement is performed on the surface of the copper alloy plate by X-ray diffractometry, and the integral intensity I _(hkl) of the diffraction peak of the predetermined orientation (hkl) plane is measured. At the same time, the integrated intensity I _{0 (hkl)} of the diffraction peak of the (hkl) plane is also measured for the same portion as the random orientation sample. The degree of development of the (hkl) surface on the surface of the copper alloy plate is evaluated by using the value of I _(hkl) / Io _(hkl) .

By controlling the I ₍₂₀₀₎ / I _{0 (200)} to 1.0 or more, preferably 2.0 or more, on the surface of the product of the copper alloy sheet according to the embodiment of the present invention, the moldability is remarkably improved. The higher the I ₍₂₀₀₎ / I _{0 (200)} , the more the Cube bearing is developed. The upper limit value of I ₍₂₀₀₎ / I _{0 (200)} is not regulated in terms of moldability improvement, but I ₍₂₀₀₎ / I _{0 (200)} of the present invention is typically 10.0 or less.

(Residual stress)

In the copper alloy sheet according to the embodiment of the present invention, the stress relaxation property is remarkably improved by adjusting the residual stress on the product surface to 200 MPa or less, preferably 100 MPa or less. Here, the residual stress of the present invention is obtained by measuring the change of the (113) plane interval with respect to the X-ray incidence angle by using the X-ray diffraction method. In the measurement direction, the X-ray incidence angle is changed in the plane parallel to the rolling direction and the thickness direction, respectively, to obtain the residual stress value occurring parallel to the rolling direction. It is possible to measure the residual stress value in other crystal planes or directions, but when measured under the conditions, the measurement deviation is the smallest, and the best correlation is obtained between the residual stress value and the stress relaxation. In addition, the residual stress of the copper alloy sheet is often calculated from the amount of deflection of the plate when one side surface of the plate is etched (Sudohare: Residual stress and strain, Uchida Rokakuhosha, (1988), p. 46.), there was no correlation with the stress relaxation in the residual stress values obtained by this etching method.

(thickness)

The thickness of the product is preferably 0.1 to 2.0 mm. If the thickness is excessively thin, the cross-sectional area of the conductive part becomes small to increase the heat generation in the passage, which is unsuitable as a material for a connector or the like to which a large current flows and is also deformed by a slight external force. On the other hand, if the thickness is excessively large, molding processing becomes difficult. From this viewpoint, the more preferable thickness is 0.2 to 1.5 mm. By setting the thickness within the above range, heat generation in communication can be suppressed, and moldability can be improved.

(Usage)

The copper alloy sheet according to the embodiment of the present invention can be suitably used for electronic parts such as terminals, connectors, relays, switches, sockets, bus bars, lead frames and heat sinks used in electric and electronic devices and automobiles , And is particularly useful for applications of high current electric components such as connectors and terminals for large currents used in electric vehicles and hybrid vehicles, and applications of heat dissipation electronic components such as liquid crystal frames used in smart phones and tablet PCs.

Here, the high-current electronic component is not particularly limited and includes those generally used for large currents. For example, a current of 10 amperes or more, more typically 30 amperes or more, and more typically 50 amperes or more Represents an electronic component. In electric connectors and hybrid electric connectors, currents exceeding 100 amperes may flow.

(Manufacturing method)

In a typical manufacturing process of the Korson alloy, the raw materials such as electric copper, Ni, Co, and Si are first dissolved in the melting furnace to obtain a molten metal having a desired composition. Then, the molten metal is cast into an ingot. Then, the desired thickness and properties are finished in the order of hot rolling, cold rolling, solution treatment, aging, final cold rolling, and deformation removal annealing. After the heat treatment, the surface may be pickled or polished to remove the surface oxide film generated during the heat treatment.

In the present invention, a heat treatment (hereinafter also referred to as preliminary annealing) and a cold rolling at a relatively low cost (hereinafter also referred to as light rolling) may be performed before the solution treatment to obtain the crystal orientation.

The preliminary annealing is carried out for the purpose of partially producing recrystallized grains in a rolled structure formed by cold rolling after hot rolling. The ratio of the recrystallized grains in the rolled structure has an optimum value, and even if it is excessively large or excessively large, the above-described crystal orientation can not be obtained. The optimum ratio of recrystallized grains is obtained by adjusting the preliminary annealing conditions so that the softness S defined below is from 0.2 to 0.8, more preferably from 0.3 to 0.7.

FIG. 1 illustrates the relationship between annealing temperature and tensile strength when an alloy according to the present invention is annealed at various temperatures. A specimen with a thermocouple attached thereto was inserted into a tubular furnace at 1000 ° C, and when the specimen temperature measured at the thermocouple reached a predetermined temperature, the specimen was taken out from the furnace, water cooled, and the tensile strength was measured. Recrystallization proceeds at a sample arrival temperature of 500 to 700 ° C, and the tensile strength is rapidly lowered. The gradual decrease in tensile strength on the high temperature side is due to the growth of recrystallized grains.

The degree of softening S in the preliminary annealing is defined by the following equation.

S = (? ₀ -?) / (? ₀ -? ₉₅₀ )

Where? ₀ is the tensile strength before annealing,? And? ₉₅₀ are the tensile strength after pre-annealing and after annealing at 950 占 폚, respectively. The temperature of 950 占 폚 is adopted as a reference temperature for determining the tensile strength after recrystallization in that the alloys according to the present invention are annealed at 950 占 폚 to be stably completely recrystallized.

If the degree of softening is out of the range of 0.2 to 0.8, I ₍₂₀₀₎ / I _{0 (200)} becomes less than 1.0 on the surface of the copper alloy plate. The temperature and time of the preliminary annealing are not particularly limited, and it is important to adjust the degree of softening S to the above range. In general, in the case of using a continuous annealing furnace, the furnace temperature is in the range of 400 to 750 ° C for 5 seconds to 10 minutes, and in the case of the batch annealing furnace, the temperature is in the range of 350 to 600 ° C for 30 minutes to 20 hours .

The preliminary annealing conditions can be set by the following procedure.

(1) The tensile strength (? ₀ ) of the material before the pre-annealing is measured. The tensile test may be carried out in parallel with the rolling direction (the same shall apply hereinafter).

(2) The material before the pre-annealing is annealed at 950 占 폚. Specifically, the material with the thermocouple is inserted into a tubular furnace at 1000 ° C., and when the sample temperature measured at the thermocouple reaches 950 ° C., the sample is taken out from the furnace and cooled.

(3) The tensile strength (? ₉₅₀ ) of the material after the annealing at 950 占 폚 is obtained.

(4) For example, when σ ₀ is 800 MPa and σ ₉₅₀ is 300 MPa, tensile strengths corresponding to softenings of 0.20 and 0.80 are 700 MPa and 400 MPa, respectively.

(5) The conditions of the preliminary annealing are determined so that the tensile strength after annealing is 400 to 700 MPa.

After the preliminary annealing, prior to the solution treatment, light rolling is performed at a working rate of 3 to 50%. If the degree of processing is out of the range of 3 to 50%, I ₍₂₀₀₎ / I _{0 (200)} becomes less than 1.0. Here, r (%) = (t ₀ - t) / t ₀ × 100 (t ₀ : plate thickness before rolling, t: plate thickness after rolling) Given.

Next, the means for adjusting the residual stress to 200 MPa or less in the above-described manufacturing process to which the preliminary annealing and the light rolling are added is not limited to a specific method. For example, the conditions of the deformation- .

The deformation-removing annealing of the present invention is carried out using a continuous annealing furnace. In the case of a batch furnace, since the material is heated in a state of being wound in a coil, the material deforms during heating, and warpage occurs in the material. Thus, the batch is unsuitable for the strain relief annealing of the present invention.

In the continuous annealing furnace, the furnace temperature was set to 300 to 700 ° C, the heating time was appropriately adjusted in the range of 5 seconds to 10 minutes, and the 0.2% proof stress after deformation removal annealing was set to 10 To 50 MPa lower, preferably 15 to 45 MPa lower. The tension applied to the material in the continuous annealing furnace is adjusted to 1 to 5 MPa, more preferably 1 to 4 MPa. By performing deformation removal annealing under this condition, the residual stress is reduced. Further, the 0.2% proof stress can be measured by carrying out a tensile test parallel to the rolling direction.

Even if the amount of decrease in the 0.2% proof stress is too small or too large, the reduction of the residual stress due to the deformation removing annealing becomes insufficient and it becomes difficult to adjust the residual stress to 200 MPa or less. Further, even if the tension is excessively large, the reduction of the residual stress due to the deformation removing annealing becomes insufficient, and it becomes difficult to adjust the residual stress to 200 MPa or less. On the other hand, if the tensile force is too small, the material passing through the annealing furnace may come into contact with the furnace wall, resulting in scratches on the surface or edge of the material.

A preferred manufacturing method related to the alloy of the present invention is as follows in the order of the process.

(1) Ingot casting (thickness 20 to 300 mm)

(2) Hot rolling (temperature 800 ~ 1000 ℃, thickness 3 ~ 20 ㎜)

(3) Cold rolling

(4) Preliminary annealing (softening degree: 0.20 to 0.80)

(5) Light rolling (processing degree: 3 to 50%)

(6) Solution treatment (700 ~ 950 ℃ for 5 ~ 300 seconds)

(7) Aging treatment (2 ~ 20 hours at 350 ~ 600 ℃)

(8) Final cold rolling (processing degree: 3 to 80%)

(9) Deformation removal annealing (at a temperature of 300 to 700 ° C for 5 seconds to 10 minutes, a tensile force of 1 to 5 MPa, a 0.2% strength decrease amount of 10 to 50 MPa)

For the processes (2) (6) and (7), the general production conditions of the Korson alloy may be selected.

The final cold rolling 8 is indispensable for high strength. When the degree of processing is less than 3%, it is difficult to adjust the 0.2% proof stress to 500 MPa or more, and when it exceeds 80%, the molding workability remarkably decreases. Further, in the case of a normal cornstone alloy, cold rolling is sometimes carried out between the solution treatment (6) and the aging treatment (7). When the cold rolling is performed, I ₍₂₀₀₎ / I ₀ , It is not preferable to carry out the cold rolling in the present invention.

Example

Examples of the present invention will be described below with reference to comparative examples. However, these examples are provided to better understand the present invention and its advantages, and are not intended to limit the invention.

The alloy element was added to molten copper and then cast into an ingot having a thickness of 200 mm. The ingot was heated at 950 占 폚 for 3 hours and hot rolled to form a plate having a thickness of 15 mm. Thereafter, processing and heat treatment were carried out in the following order.

(1) cold rolling

(2) Preliminary annealing: Using a continuous annealing furnace, the heating temperature was set to 30 seconds, the furnace temperature was adjusted between 500 and 750 DEG C, and the degree of softening was variously changed. In some examples, no pre-annealing was performed.

(3) Light rolling: The degree of processing was changed.

(4) Solution treatment: The continuous annealing furnace was used to adjust the furnace temperature to 800 캜 and the heating time to 1 to 10 minutes so that the grain size after solution treatment became 5 to 20 탆.

(5) Aging treatment: Using a batch furnace, the heating time was set to 5 hours, and the furnace temperature was adjusted between 350 and 600 캜 so as to maximize the tensile strength.

(6) Final cold rolling: The degree of processing was changed.

(7) Deformation removal annealing: Using a continuous annealing furnace, the furnace temperature was set to 500 占 폚, the heating time was adjusted between 1 second and 15 minutes, and the amount of decrease in the 0.2% . In addition, the tension added to the material in the furnace was varied variously. Deformation removal annealing was not performed in some examples.

The following measurements were made on the material after deformation removal annealing (after final cold rolling in the case of no deformation removal annealing).

(ingredient)

Alloy element concentrations were analyzed by ICP-mass spectrometry.

(0.2% proof)

A test piece No. 13B specified in JIS Z2241 was taken in such a manner that the tensile direction was parallel to the rolling direction, and a tensile test was conducted in parallel with the rolling direction in accordance with JIS Z2241 to obtain a 0.2% proof stress.

(Conductivity)

The test piece was taken so that the longitudinal direction of the test piece was parallel to the rolling direction, and the conductivity at 20 캜 was measured by a division method according to JIS H0505.

(X-ray diffraction of the product)

The X-ray diffraction integral intensity of the (200) plane was measured on the surface of the material. The X-ray diffraction integral intensity of the (200) plane was measured for copper powder (copper (powder), 2N5, > 99.5%, 325 mesh, manufactured by Kanto Kagaku Co., Ltd.). As the X-ray diffraction apparatus, RINT2500 manufactured by RIGAKU Co., Ltd. was used, and measurements were made with Cu tube at a tube voltage of 25 kV and a tube current of 20 mA.

(Residual stress)

The residual stress occurring in the direction parallel to the rolling direction with respect to the (113) plane of the copper alloy plate was determined by X-ray diffraction. The measurement principle will be described below.

For example, when tensile residual stress is present as shown in FIG. 2, the angle (?) Between (a)? (B)? (C) and the sample surface normal N and the lattice plane normal N ' As the size increases, the lattice plane spacing increases in this order. Since the crystal plane interval is proportional to the magnitude of the stress, the residual stress (?) Can be obtained by measuring the lattice plane spacing, that is, the diffraction angle (2?) In each?

Where σ is stress, E is Young's modulus, ν is Poisson's ratio, and θ ₀ is the standard bracket angle. K is a constant determined by the material and the measurement wavelength. The relationship between ² ? And sin ² ? Is shown and the gradient is found by the least squares method, and this is multiplied by K to obtain the residual stress value.

(Molding processability)

Using a test machine manufactured by Ericsson, a cup was produced under the conditions of a blank diameter:? 64 mm, a punch (punch) diameter:? 33 mm, a sheet pressure: 3.0 kN, and a lubricant: grease.

This cup was placed on a glass plate with the open end side down, and the gap between the ears and the glass plate was read and measured with a microscope. The average value of the gaps in the recesses between the four ears And the height of the ear.

In addition, the appearance of the cup was visually observed, and the presence or absence of surface roughness was judged.

The processability was evaluated based on the following criteria.

⊚: Ears having a height of 0.5 mm or less and no surface roughness

?: The ear height was 0.5 mm or less, and the surface roughness was slightly

X: Ears having a height of more than 0.5 mm or surface roughness

(Stress relaxation rate)

A specimen having a width of 10 mm and a length of 100 mm was sampled so that the longitudinal direction of the specimen was parallel to the rolling direction. As shown in Fig. 3, the specimen was subjected to y ₀ deflection with a position of l = 50 mm as a point of action, and the stress (s) corresponding to 80% of the 0.2% proof stress in the rolling direction was loaded. y ₀ was obtained from the following equation.

y ₀ = (2/3) · l ² · s / (E · t)

Where E is the Young's modulus in the rolling direction and t is the thickness of the sample. At 150 ℃ after 3000 hours heating to remove the load, and also measuring the permanent deformation (H) y, such as four, and calculating the stress relaxation ratio {[y (㎜) / y 0 (㎜)] × 100 (%)} Respectively.

When the stress relaxation rate was 30% or less, the stress relaxation characteristics were regarded as good.

Table 1 shows the product thickness and alloy composition, and Table 2 shows the manufacturing conditions and evaluation results.

In Examples 1 to 31, at least one of Ni and Co was adjusted to 0.8 to 5.0 mass% in total and Si was adjusted to 0.2 to 1.5 mass%, and the degree of pre-annealing and the degree of softening of 0.2 to 0.8, The material is subjected to a continuous annealing furnace at a tension of 1 to 5 MPa in a deformation removing annealing process to obtain a 0.2 to 10% 50 MPa. As a result, and the I ₍₂₀₀₎ / I _{0 (200)} is 1.0 or more, in the I ₂₀₀ / I ₀ to less than ₂₀₀ 2.0 Examples 1 ~ 23, the evaluation of the moldability and the ◎, I _{(200 )} / I _{0 (200)} was 1.0 or more and less than 2.0, evaluation of the molding processability was?. At the same time, the residual stress became 200 MPa or less and the stress relaxation rate became 30% or less. Also, a conductivity of 30% IACS or more and a 0.2% proof stress of 500 MPa or more were obtained.

In Comparative Examples 9 and 10, since the softening degree of the preliminary annealing was out of the range of 0.2 to 0.8, since the preliminary annealing and the light rolling were not carried out in Comparative Examples 1 to 8, I ₍₂₀₀₎ / I _{0 (200)} was less than 1.0, and the evaluation of the molding processability was evaluated as X because the temperature was out of the range of 3 to 50%.

Comparative Examples 14 to 25 were subjected to light rolling with a degree of softening of 0.2 to 0.8 and a degree of pre-annealing of 3 to 50%. As a result, I ₍₂₀₀₎ / I _{0 (200)} The evaluation is ◎ or ○. However, since the degeneration annealing was not performed in Comparative Example 14, the degradation amount of the 0.2% proof stress in the degenerative annealing was small in Comparative Examples 15 to 18, and therefore, Comparative Examples 19 and 20 were 0.2 In Comparative Examples 21 to 24, since the material tension in the furnace exceeded 5 MPa, the residual stress exceeded 200 MPa and the stress relaxation rate exceeded 30%.

In Comparative Example 16, since the working degree in the final cold rolling was not less than 3%, the 0.2% proof stress after deformation removing annealing did not reach 500 MPa.

Claims (4)

At least one of Ni and Co in a total amount of 0.8 to 5.0 mass% and Si in an amount of 0.2 to 1.5 mass%, the balance of copper and inevitable impurities, a 0.2% proof stress of 500 MPa or more and a conductivity of 30% IACS or more ₍₂₀₀₎ / I _{0 (200)} ≥ 1.0, and a residual stress occurring in a direction parallel to the rolling direction with respect to a (113) plane obtained by X-ray diffractometry is 200 MPa or less. Alloy plate. (Where I _(hkl) and Io _(hkl) are the diffraction integral intensities of the (hkl) plane obtained by X-ray diffraction on the surface of the copper alloy plate and the copper powder, respectively) The method according to claim 1,
Wherein at least one of Sn, Zn, Mg, Fe, Ti, Zr, Cr, Al, P, Mn, B and Ag is contained in a total amount of 3.0 mass% or less. An electronic component for a large current using the copper alloy plate according to claim 1 or 2. A heat dissipation electronic component using the copper alloy sheet according to any one of claims 1 to 3.

Images