TWI582249B - Copper alloy sheet and method of manufacturing the same - Google Patents

Description

Copper alloy sheet and manufacturing method thereof

The present invention relates to a copper alloy sheet material for a lead frame, a connector, a terminal material, a relay, a switch, a socket, and the like for use in an electric or electronic machine, and a method of manufacturing the same.

The properties required for copper alloy materials used in electrical and electronic applications include electrical conductivity, guaranteed stress (falling stress), tensile strength, bending workability, and stress relaxation resistance. In recent years, with the miniaturization, weight reduction, high functionality, high-density construction of electrical and electronic equipment, and the high temperature of the use environment, the level required for these characteristics has been increasing.

Conventionally, materials for electrical and electronic equipment have been widely used in addition to iron-based materials, such as copper bronze, red brass, and brass. These alloys are strengthened by solid solution strengthening of Sn or Zn in combination with work hardening by cold working such as calendering or drawing. In this method, the electrical conductivity is insufficient, and since high strength is obtained by cold working by applying a high-pressure rate, the bending workability or the stress relaxation resistance is insufficient.

Instead of the strengthening method, there is a precipitation strengthening method in which a fine second phase is precipitated in a material. This strengthening method has the advantage of increasing the strength and simultaneously increasing the conductivity, and thus is carried out in most alloy systems. However, with the recent miniaturization of parts used in electronic machines or automobiles, copper alloys have gradually subjected to bending processing of materials having higher radii to higher strength materials, and copper alloy sheets having excellent bending workability are strongly required. Furthermore, even in the case of a sheet having high strength, high elasticity, and good bending workability, it is in the parallel direction of rolling and rolling. It is also not good to have poor characteristics in the straight direction. It is important to show good characteristics in any direction. In particular, when used as an ultra-small terminal, the butt mold is subjected to microfabrication in a narrow width, and it is also important here to exhibit good characteristics in either direction. In the conventional Cu-Ni-Si-based copper alloy, in order to obtain high strength, the rolling rate can be increased to obtain a large work hardening, but as described above, the bending workability is deteriorated, and it is difficult to achieve high strength. With good bending workability.

In response to the demand for improved bending workability, there have been several proposals for solving the problem by controlling the crystal orientation. For example, in the Cu-Ni-Si copper alloy, there are the following proposals. Patent Document 1 discloses that in a Cu-Ni-Si-based copper alloy, the crystal grain size and the X-ray diffraction intensity I from the {311}, {220}, and {200} planes satisfy the crystal orientation of a certain condition. In the case, the bending workability is excellent. Further, in the case of the Cu-Ni-Si-based copper alloy, the X-ray diffraction intensity from the {200} plane and the {220} plane satisfies the crystal orientation of a certain condition, and the bending workability is excellent. . Moreover, in the Cu-Ni-Si-based copper alloy, it is disclosed that the bending workability is excellent by controlling the ratio of the cube orientation {001}<100> to 50% or less. Patent Document 4 discloses that in a Cu-Ni-Si-based copper alloy, a crystal structure in a strained state is recrystallized by a relatively strong cold working to become a crystal structure having a small anisotropy, and the elongation is improved by increasing the elongation. The bending workability becomes good. Patent Document 5 discloses that in the Cu-Ni-Si-based copper alloy, the ratio of the crystal grain size to the cubic orientation {001}<100> is controlled to 20 to 60%, so that the intensity anisotropy is small and curved. Excellent processability. Patent Document 6 discloses that in a Cu-Ni-Si-based copper alloy, by crystal grain size and cubic The ratio of the orientation {001}<100> is controlled to 5 to 50% without loss of mechanical strength, electrical conductivity or bending workability and improvement of fatigue characteristics.

In the inventions described in Patent Document 1 and Patent Document 2, the analysis of the crystal orientation of the X-ray diffraction from a specific surface is a particularly specific surface in the distribution of the crystal orientation having a certain width. Moreover, in the invention described in Patent Document 3, the control of the crystal orientation is performed by reducing the calendering rate after the solution heat treatment. Further, the area and dispersibility of the cubic azimuth crystal grains are not described, and the anisotropy of the bending workability and the strength is not disclosed. In the invention described in Patent Document 4, the crystal structure in a strain state is recrystallized by a relatively strong cold rolling to realize a crystal structure having a small anisotropy, and the elongation is improved to achieve good bending workability. However, the improvement in characteristics by the crystal orientation control has not been performed. In the invention described in Patent Document 5, the cubic azimuth is aggregated by adjusting the rolling reduction ratio in the cold rolling before the solution treatment and the temperature increase rate in the solution treatment, and the strength and the bending workability are lowered. Anisotropy. However, in Patent Document 5, since the temperature rise rate in the solution treatment is slow, the temperature rise time is long, and as a result, the cubic azimuth crystal grains are coarse, and the cubic orientation crystal grains are poorly dispersed, and the intensity anisotropy is also poor. Larger. Further, in the invention described in Patent Document 6, the cold rolling before the solution treatment is performed at a high reduction ratio of 85 to 99.8%, and the heating temperature and the holding time in the subsequent solution treatment are adjusted. Aggregate the cubic orientation and improve fatigue characteristics. However, in Patent Document 6, the result of the solution treatment is that the obtained cubic azimuth crystal grains are coarse, and the dispersibility of the cubic azimuth crystal grains is poor, and the anisotropy of the strength is also large.

Also required for copper alloy materials used in electrical and electronic equipment applications One of the characteristic items requires a Young's modulus (longitudinal coefficient of elasticity) to be low. In recent years, as the miniaturization of electronic components such as connectors has progressed, the requirements for the dimensional accuracy of the terminals or the tolerances of the press working have become strict. By reducing the Young's modulus of the material, the influence of the dimensional change on the contact pressure can be reduced, so that the design can be made easy. In the measurement of the Young's modulus, there are two methods: a method of calculating the slope of the elastic region of the stress-strain line graph obtained by the tensile test, and the stress according to the bending of the beam (cantilever beam) - The method of calculating the slope of the elastic region of the strain line diagram.

[Patent Document 1] Japanese Laid-Open Patent Publication No. 2006-009137

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2008-013836

[Patent Document 3] Japanese Laid-Open Patent Publication No. 2006-283059

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2005-350695

[Patent Document 5] Japanese Patent Laid-Open Publication No. 2011-162848

[Patent Document 6] Japanese Patent Publication No. 2011-012321

In view of the problems of the prior art as described above, an object of the present invention is to provide an excellent bending workability and excellent strength, and each of the characteristics has less anisotropy in the rolling parallel direction and the rolling vertical direction, and is suitable for electrical, Lead frame, connector, terminal material for electronic equipment, etc., and copper alloy plate materials such as connectors or terminal materials for automobiles, relays, switches, etc. Further, a method for producing a copper alloy sheet material as described above is provided as another subject.

The inventors of the present invention conducted intensive studies on copper alloys suitable for use in electrical and electronic equipment, and found them in Cu-Ni-Si copper alloy sheets. The bending workability, strength, and electrical conductivity are greatly improved, and the aggregation ratio in the cubic orientation is correlated with the bending workability. Further, in the copper alloy sheet material having the crystal orientation and characteristics, an alloy composition having an effect of further increasing the strength was found, and in addition, the following copper alloy sheet material was found, which was added to the alloy system to have a lossless electrical conductivity. Or an element that bends the workability and enhances the strength. Further, in order to realize the crystal orientation as described above, the aggregation ratio based on the cubic orientation has a correlation with the bending workability, and a manufacturing method having a specific step has been found. The present invention is based on these findings and the results are completed.

That is, according to the present invention, the following means are provided.

(1) A copper alloy sheet material having a composition containing 1.0% by mass or more and 5.0% by mass or less of Ni, 0.1% by mass or more and 2.0% by mass or less of Si, and the balance being composed of copper and unavoidable impurities; In the crystal orientation analysis using the electron backscatter diffraction method, the area ratio of the crystal grains having an orientation within 15 degrees from the cubic orientation {001}<100> is 5% or more and 50% or less, and has a self-cubic orientation { 001}<100> The crystal grains having an orientation within a range of 15° or less are dispersed in 40 or more and 100 or less in a 60 μm square.

(2) A copper alloy sheet material having a composition containing 1.0% by mass or more and 5.0% by mass or less of Ni, 0.1% by mass or more and 2.0% by mass or less of Si, and a total of 0.005% by mass or more and 1.0% by mass or less selected from the group consisting of At least one of the group consisting of Sn, Zn, Ag, Mn, B, P, Mg, Cr, Zr, Fe, and Hf, and the remainder consisting of copper and unavoidable impurities; In the crystal orientation analysis using the electron backscatter diffraction method, the area ratio of the crystal grains having an orientation within 15 degrees from the cubic orientation {001}<100> is 5% or more and 50% or less, and has a self-cube orientation. {001}<100> The crystal grains having an orientation within a range of 15° or less are dispersed in 40 or more and 100 or less in a 60 μm square.

(3) The copper alloy sheet according to (1) or (2) above, wherein the average crystal grain size of the crystal grains having an orientation within 15 degrees from the cubic orientation {001}<100> is 1.8 μm ² or more and 45.0. Below μm ² .

(4) The copper alloy sheet material according to any one of the above (1) to (3), wherein the crystal grains of the base material have an average crystal grain size of 50 μm ² or less.

(5) The copper alloy sheet material according to any one of (1) to (4), wherein a difference between a bending coefficient in a rolling parallel direction and a bending coefficient in a rolling perpendicular direction is 10 GPa or less in absolute value, and the rolling is parallel. The difference between the guaranteed stress and the guaranteed stress in the vertical direction of the rolling is 10 MPa or less in absolute value.

(6) A method for producing a copper alloy sheet, wherein the ingot obtained by casting the copper alloy material is subjected to homogenization heat treatment and hot rolling, and further formed into a thin plate by cold rolling, and then the solute atom in the sheet is further subjected to The intermediate solution heat treatment of the solid solution; the copper alloy raw material is composed of the alloy composition of the copper alloy sheet material in the above item (1) or (2), and the method for producing the copper alloy sheet includes the following steps in sequence Formation: The above homogenization heat treatment is performed at 800 ° C or more and 1020 ° C or less for 3 minutes to 10 hours. After the cold rolling is performed at a rolling ratio of 80% or more and 99.8% or less, the intermediate annealing is performed for 5 seconds to 20 hours at a temperature not lower than the recrystallization temperature, that is, 400 ° C to 700 ° C, and further heated to 100 ° C or higher and 400 ° C. After that, the intermediate temperature rolling is performed at a temperature of 5% or more and 50% or less at this temperature, and then the intermediate solution heat treatment is performed at 600 ° C to 1000 ° C for 5 seconds to 1 hour, and the temperature is 400 ° C or more and 700 ° C or less. The aging precipitation heat treatment is performed for 5 minutes to 10 hours.

According to the copper alloy sheet material of the present invention, it is possible to provide a copper alloy sheet material which is excellent in bending workability, exhibits excellent strength, and has different anisotropy in each of the rolling parallel direction and the rolling perpendicular direction. Therefore, it is possible to provide a copper alloy sheet material having characteristics such as a lead frame, a connector, a terminal material, and the like which are particularly suitable for electric and electronic equipment, and a connector or a terminal material, a relay, a switch, and the like for an automobile or the like.

Further, according to the production method of the present invention, the above copper alloy sheet material can be preferably produced.

The above and other features and advantages of the invention will be apparent from the description and appended claims

A preferred embodiment of the copper alloy sheet of the present invention will be described. Furthermore, the "sheet" in the present invention also includes "bar".

The copper alloy sheet material of the present invention has a composition containing 1.0% by mass or more and 5.0% by mass or less of Ni, 0.1% by mass or more and 2.0% by mass or less. Si, and the remainder is composed of copper and unavoidable impurities. Ni is preferably 3.0% by mass or more and 5.0% by mass or less, and Si is 0.5% by mass or more and 2.0% by mass or less. It is particularly preferable to set Ni to 4.0% by mass or more and Si to 1.0% by mass or more.

Further, in the crystal orientation analysis by the electron backscatter diffraction method, the area ratio of the cubic orientation {001}<100> (hereinafter sometimes referred to as the cubic azimuth area ratio) is 5% or more and 50% or less, preferably. It is 10% or more and 45% or less, more preferably 15% or more and 40% or less, and particularly preferably 20% or more and 35% or less.

In addition, the copper alloy sheet may contain 1.0% by mass or more and 5.0% by mass or less of Ni, 0.1% by mass or more and 2.0% by mass or less of Si, and may be contained in a total amount of 0.005% by mass or more and 1.0% by mass or less, selected from the group consisting of Sn and Zn. At least one of a group consisting of Ag, Mn, B, P, Mg, Cr, Zr, Fe, and Hf. The total of at least one selected from the group consisting of Sn, Zn, Ag, Mn, B, P, Mg, Cr, Zr, Fe, and Hf is preferably 0.01% by mass or more and 0.9% by mass or less, more preferably 0.03% by mass. % or more is 0.8% by mass or less, and particularly preferably 0.05% by mass or more and 0.5% by mass or less. In this case, a preferred range of the preferable content, a particularly preferable content, and a cubic azimuthal area ratio of Ni and Si, and a particularly preferable range are the same as the above range.

Further, in each of the copper alloy sheet material having self-standing side orientation {001} <100> of the average grain area of crystal grains of less than 15 ° offset orientation of 1.8 m ² or more is preferably ² or less 45.0μm, more preferably 3.8μm ² or less than ² 36.0m. 6.0 m ² or more and further preferably ² or less 28.8μm, and particularly preferably ² or less than 10.0 m ² 25.0μm.

In this specification, it is sometimes omitted to have a self-cube orientation. {001}<100> The average crystal grain area of the crystal grains with an orientation within 15° is called the cubic azimuth area ratio or the area ratio of the cubic azimuth {001}<100>. Further, the crystal grains having azimuth within a range of 15° from the cubic orientation {001}<100> are sometimes omitted, and are referred to as cubic azimuth grains or crystal grains having a cubic orientation {001}<100>.

The average crystal grain area of the base material containing crystal grains of cubic orientation is preferably 40 μm ² or less, and more preferably 5 to 30 μm ² . The average value of the crystal grain area was calculated from the measurement results of EBSD (Electron Back Scatter Diffraction) in the range of 300 × 300 μm of the sheet plane, and the average crystal grain area was obtained.

Further, in the crystal orientation analysis by the electron backscatter diffraction method, crystal grains having a cubic orientation {001}<100> are distributed in 40 or less and 100 or less in 60 μm square and have uniform dispersibility. The crystal grains of the cubic orientation {001}<100> are preferably distributed in a range of 45 or more and 95 or less in a 60 μm square and have an isodispersity, and particularly preferably have a distribution of 50 or more and 90 or less and have an isodispersity.

Further, it is preferable that the bending workability in the rolling parallel direction and the rolling vertical direction is not caused by the 180° U-tight bending in the narrow width bending process of 1 mm width or less, and cracking occurs on the curved surface.

Further, the difference between the bending coefficient in the rolling parallel direction (//) and the bending coefficient in the rolling perpendicular direction (⊥) is preferably 10 GPa or less, more preferably 8 GPa or less, and particularly preferably 5 GPa or less in absolute value. The difference between the guaranteed stress in the rolling parallel direction and the guaranteed stress in the vertical direction of the rolling is preferably 10 MPa or less, more preferably 8 MPa or less, and particularly preferably 5 MPa or less in absolute value. The smaller the difference, the smaller the isotropic property, so it is preferable. Ideally, the difference between these is 0 (Zero), that is, the value of the rolling parallel direction and the rolling vertical direction are preferably the same.

When the area ratio of the cubic alloy {001}<100> and the average crystal grain area thereof, and further preferably the average crystal grain area of the base material are both within the above range, the copper alloy sheet of the present invention is not caused by 180°U. The tightness is bent at the apex of the curved portion to cause cracking, and good bending characteristics are obtained, and the bending anisotropy and the stress anisotropy are ensured to be small. On the other hand, when the area ratio is too small or the average crystal grain size is too large, or when the average crystal grain size of the base material is too large, cracks are likely to occur at the apex of the bent portion, and good results cannot be obtained. The bending property, and the bending anisotropy and the guaranteed stress anisotropy become large.

The copper alloy sheet material of the present invention contains 1.0% by mass to 5.0% by mass of Ni and 0.1% by mass to 2.0% by mass of Si. Thereby, the Ni-Si-based compound (Ni ₂ Si phase) is precipitated in the Cu substrate to improve strength and conductivity. On the other hand, if the content of Ni is too small, strength cannot be obtained, and if it is too large, precipitation at the time of casting or hot working does not contribute to strength improvement, and strength equivalent to the amount of addition cannot be obtained, and hot workability and bending workability are lowered. . Further, since Si and Ni form a Ni ₂ Si phase, the amount of Si added is determined when the amount of Ni is determined. However, if the amount of Si is too small, strength cannot be obtained, and if the amount of Si is too large, the same problem as in the case where the amount of Ni is excessive is generated. Therefore, the addition amount of Ni and Si is preferably set to the above range.

Next, the area ratio of the cubic orientation {001}<100> will be described.

In order to improve the bending workability of a copper alloy sheet, the present inventors directed The cause of the crack generated in the bent portion was investigated. As a result, it was confirmed that the plastic deformation was locally developed to form a shear deformation zone, and the formation and connection of the micropores were caused by local work hardening, thereby achieving the forming limit. As a countermeasure against this, it has been found that it is effective to increase the ratio of the crystal orientation in which work hardening is not easily caused by bending deformation. In other words, when the area ratio of the cubic orientation {001}<100> is 5% or more and 50% or less as described above, it is found that good bending workability is exhibited.

When the area ratio of the cubic orientation {001}<100> is within the above range, the above-described effects can be sufficiently exerted. Further, even if the cold calendering after the recrystallization treatment is not carried out at a low rolling ratio, the strength is not significantly lowered within the above range, which is preferable. That is, the cold rolling process after the recrystallization treatment can be performed at a high rolling ratio without significantly lowering the strength. On the other hand, when the area ratio of the cubic azimuth {001}<100> is too low, the bending workability is deteriorated, and conversely, when the area ratio of the cubic azimuth {001}<100> is too high, the strength is lowered. . Therefore, from the above viewpoints, the area ratio of the cubic orientation {001}<100> is 5% or more and 50% or less, preferably 10% or more and 45% or less, and more preferably 15% or more and 40% or less. The range of the best is 20% or more and 35% or less.

Next, the orientation other than the cubic orientation of the above range will be described. In the copper alloy sheet of the present invention, the S orientation {3 2 1}<4 3 6>, the copper orientation {1 2 1}<1-1 1>, and the D orientation {4 11 4}<11- are generated. 8 11>, brass (brass) orientation {1 1 0}<1-1 2>, Goss orientation {1 1 0}<0 0 1>, RDW orientation {1 0 2}<0 1 0> Wait. Regarding the azimuthal components, the cubic azimuth area ratio is as long as the area of all the azimuths observed Within the above range, it can be tolerated.

As described above, an electron backscatter diffraction analysis (hereinafter referred to as EBSD) method is used in the analysis of the above crystal orientation in the present invention. The EBSD method is an abbreviation of Electron BackScatter Diffraction, which uses an electron back-scattering pattern (EBSP) generated by irradiating an electron beam to a point on a surface of a sample in a scanning electron microscope (SEM). ) to analyze the crystal orientation of a local region or the crystal orientation analysis technique of a crystalline structure.

The area of the sample containing 1 mm square of 200 grains or more was scanned in a step of 0.1 μm and the crystal orientation was analyzed. The measurement area was set to 300 μm × 300 μm in accordance with the size of the crystal grains of the sample. The area ratio of each azimuth is a ratio of the area of the crystal grains having an orientation within a range of 15° from the ideal azimuth of the cubic azimuth {001}<100> with respect to the total measured area. The information obtained in the orientation analysis using the EBSD method includes the orientation information of the electron beam penetrating sample to a depth of several 10 nm, but is very small with respect to the measured width, and thus is described as an area ratio in the present specification. Further, since the azimuth distribution varies in the direction of the plate thickness, it is preferable to use the EBSD method for the orientation analysis to arbitrarily select a plurality of points in the plate thickness direction and take an average value. Unless otherwise specified in the present application, the area measured by the above method is referred to as the area ratio of the crystal face having a certain crystal orientation.

Next, the isodispersity of the crystal grains of the cubic orientation {001}<100> will be described.

In order to investigate the dispersibility of the cubic orientation crystal grains, a range of 300 μm × 300 μm was scanned in a step of 0.1 μm by a crystal orientation analysis by the EBSD method, and a total of 25 blocks were analyzed by setting the 60 μm square to one block. The area ratio, the number of the cubic azimuth grains per unit block, the average grain area, and the average grain area of the base material including the cubic azimuth particles were confirmed, and the dispersibility was investigated. "As described above, the cubic azimuth area ratio per block is 5% or more and 50% or less, the number of cubic azimuth grains is 40 or more and 100 or less, and the average crystal grain area per one cubic azimuth crystal grain. the average grain area of 1.8 m ² or less than ² 45.0μm, further comprising a base material of a cubic orientation grains is 50 m ² or less of the case "in the present invention, each of the visual field (300μm × 300μm), and the like of the cube oriented grains Quantitative for dispersibility. The equal dispersion is calculated by multiplying the area of one block (60 μm × 60 μm = 3600 μm ² ) by the cubic azimuth area ratio of the block to determine the total area of the cubic azimuth grains per block, and further The average area of each of the cubic azimuth grains in the 1 block is obtained by dividing the total area value by the number of cubic azimuth grains in the 1 block. The value obtained is the average grain area. Here, the "equal dispersion" is defined by the average grain area and the number of cubic azimuth grains per block. Here, even if the distribution state of the cubic azimuth grains is shifted, it is possible to aggregate. The dispersion was confirmed when observed in the whole of 300 × 300 μm of 25 blocks. For example, when the bending portion of the narrow width pin (0.25 mm=250 μm) of the ultra-small connector is 250×250 μm, the cube orientation group is included in at least four or more blocks, which is equivalent to dispersibility. It is assumed that even if the cubic orientation is concentrated at the corners of the adjacent four blocks as shown in FIG. 1, the dispersibility is equal, and the anisotropy of the parallel and vertical directions of rolling is also small. Here, the dispersibility (when the adjacent four blocks are set to one group and at least four or more groups) is further preferably defined even if the area of the one block is set smaller. For example, it is preferable to set the area of the 1 block to 30 μm square, and there are 10 to 25 cubic azimuth {001}<100> grains in the 1 block, and the grain of the cubic orientation {001}<100>. The area ratio is 5 to 50%, and the average grain size of the crystal grains with a cubic orientation of {001}<100> is 1.8 to 45.0 μm ² . In this case, the average crystal grain size of the crystal grains of the base material is preferably 40 μm ² or less.

When the average crystal grain size of the cubic azimuth grains is too small, the solution heat treatment is insufficient, and the unrecrystallized structure remains, and the strength and bending workability are lowered. On the other hand, when the average crystal area of the cubic azimuth crystal grains is excessively large, there is a high possibility that cracks (cracks) occur in the crystal grain portions having orientations other than the cubic azimuth grains during the bending process. Further, anisotropy may occur depending on the direction of the bend. Therefore, the average crystal area of the cubic azimuth grains is preferably set to the range as described above.

Further, the cubic azimuth crystal grains are distributed in 40 or less and 100 or less in 60 μm square and have uniform dispersibility, so that cracks are not generated at the apex of the bent portion, and good bending characteristics can be obtained, and the bending anisotropy and the stress difference are ensured. The directionality becomes smaller. On the other hand, if the number of cubic azimuth grains distributed in the 60 μm square is too small, cracks are generated at the apex of the curved portion, and good bending characteristics are not obtained, and the bending anisotropy and the stress anisotropy are ensured to be large. . On the other hand, when the number of the crystal grains is too large, the bending workability, the bending anisotropy, and the stress anisotropy are excellent, but the strength is lowered.

In particular, in the case of a narrow-width pin (for example, 0.25 mm wide) for an ultra-small connector composed of the above copper alloy sheet material, even a cubic orientation {001}<100> grain which can effectively improve bending workability is used. Area ratio range The area ratio is increased, the average grain area of the cubic azimuth grains is also large, and when the distribution of the cubic azimuth grains is uneven, the grains having azimuth other than the cubic azimuth grains are bent during the bending process. Part of the possibility of cracking (cracking) is high. Further, anisotropy may occur depending on the direction of the bend. Therefore, in the crystal orientation analysis by the EBSD method, it is preferable that the cubic azimuth crystal distribution is 60 or more and 100 or less in a 60 μm square, and has an isotropic property.

Therefore, the average grain area and dispersibility of the cubic azimuth grains are controlled in the copper alloy sheet of the present invention. Specifically, by heating to a temperature at which no recrystallization is performed in the intermediate temperature rolling before the recrystallization heat treatment, and performing rolling at a temperature of 5% or more at this temperature, strain can be applied to the entire rolled material. The introduction and release control is in a modest state. Thereby, the dispersion of the cubic orientation can be achieved. Moreover, it is also possible to control the average crystal grain area of each crystal orientation. By controlling the dispersibility, the bending workability of the narrow width pin is improved, and the anisotropy of the strength such as the bending anisotropy and the stress anisotropy is reduced.

Next, the sub-additive element added to the copper alloy sheet material of the present invention will be described.

As described above, in a preferred embodiment of the copper alloy sheet material of the present invention, in addition to the main additive elements of Ni and Si, it may be selected from the group consisting of Sn, Zn, Ag, Mn, B, P, Mg, Cr, Zr, At least one element selected from the group consisting of Fe and Hf is a sub-addition element, and the content of the sub-addition element is 0.005 mass% or more and 1.0 mass% or less, preferably 0.01 mass% or more and 0.9 mass% or less, more preferably 0.03 mass. % or more and 0.8% by mass or less, especially It is preferably 0.05% by mass or more and 0.5% by mass or less. When the total amount of the sub-addition elements is 1.0% by mass or less, it is likely to cause a risk of lowering the electrical conductivity. Moreover, when it is in the above range, the following addition effect can be utilized fully and effectively, and the electrical conductivity does not fall significantly. If it is in the range of the best, a higher addition effect and a high electrical conductivity can be obtained. On the other hand, when the content of the sub-additive element is too small, the effect of addition cannot be sufficiently exhibited. On the other hand, when the content of the sub-addition element is too large, the conductivity is lowered, which is not preferable. Hereinafter, the effect of adding each of the sub-addition elements will be described.

Among the above-mentioned sub-additive elements, Mg, Sn, and Zn enhance the stress relaxation resistance of the copper alloy sheet. Compared with the case of separately adding, in the case of adding together, the stress relaxation property is further improved by the multiplication effect. Moreover, the effect of welding embrittlement is significantly improved. The stress relaxation resistance was measured at 150 ° C for 1,000 hours in accordance with the Japanese Electronic Materials Industry Association standard specification EMAS-3003. The cantilever beam method is used to load the copper alloy sheet with an initial stress of 80% of the stress, and the displacement after the test at 150 ° C and 1000 hours is set as the stress relaxation resistance.

Among the above-mentioned sub-additive elements, Mn, Ag, B, and P enhance the hot workability of the copper alloy sheet and increase the strength.

Among the above-mentioned sub-addition elements, Cr, Zr, Fe, and Hf are finely precipitated in the base material by a compound or a monomer. The monomer is preferably precipitated at 75 nm or more and 450 nm or less, more preferably precipitated at 90 nm or more and 400 nm or less, and more preferably precipitated at 100 nm or more and 350 nm or less to contribute to precipitation hardening. Further, as a compound, it is precipitated in a size of 50 nm to 500 nm. In either case, there is an effect of making the crystal grains fine by suppressing the growth of crystal grains. The dispersion state of the crystal grains of the square orientation {001}<100> is improved, and the bending workability can be favorably improved.

Next, the bending workability of the copper alloy sheet material of the present invention will be described.

The bending workability is preferably such that the test piece subjected to the 90° W bending process is subjected to a 180° close bending process by a compression tester without causing cracks (cracks) at the apex of the bent portion.

In other words, the bending workability of the rolling parallel direction and the rolling vertical direction of the copper alloy sheet of the present invention is preferably not subjected to bending processing by 180° U close bending in a narrow width bending process of 1 mm width or less. Cracks appear on the surface.

Next, the anisotropy of the bending coefficient and the anisotropy of the guaranteed stress are explained.

The absolute value of the difference between the bending coefficient in the rolling parallel direction (//) and the bending coefficient in the rolling vertical direction (⊥) is preferably 10 GPa or less, and in this case, the anisotropy of the bending coefficient is small. Further, the absolute value of the difference between the guaranteed stress in the rolling parallel direction and the guaranteed stress in the vertical direction of the rolling is preferably 10 MPa or less. In this case, the anisotropy of the stress is ensured to be small.

Next, a preferred embodiment of the method for producing a copper alloy sheet material of the present invention will be described.

In the production of the copper alloy sheet material of the present invention, the following production method is employed: the ingot obtained by casting the copper alloy material is subjected to heat treatment (homogenization treatment) and hot rolling, and further formed into a thin plate by cold rolling. Performing an intermediate annealing that does not reach the recrystallization temperature of the above-mentioned thin plate, and after heating to 100 ° C or more and 400 ° C or less, the rolling rate is 5% or more at this temperature. The temperature is rolled (hereinafter referred to as intermediate temperature rolling), and then an intermediate solution heat treatment for resolubilizing the solute atoms in the thin plate is performed.

The copper alloy material has a composition containing 1.0% by mass or more and 5.0% by mass or less of Ni, 0.1% by mass or more and 1.0% by mass or less of Si, and, if necessary, a total of 0.005% by mass or more and 1.0% by mass or less, selected from the group consisting of Sn. At least one of a group consisting of Zn, Ag, Mn, B, P, Mg, Cr, Zr, Fe, and Hf, and the remainder is composed of copper and unavoidable impurities.

The calendering ratio herein refers to a value obtained by subtracting the cross-sectional area after calendering from the cross-sectional area before calendering, divided by the cross-sectional area before calendering, multiplied by 100, and expressed as a percentage. That is, it is represented by the following formula.

[calendering rate]={([sectional area before rolling]-[cross-sectional area after rolling])/[sectional area before rolling]}×100 (%)

Specifically, as a preferred example, the following production methods can be mentioned.

The above copper alloy raw material is cast [Step 1] to obtain an ingot. After the ingot is subjected to homogenization heat treatment [Step 2] and hot rolling [Step 3], cooling is performed immediately (for example, water bath cooling and water quenching) [Step 4]. Then, the end surface cutting is performed in order to remove the oxide film on the surface [Step 5]. Thereafter, cold rolling is performed [Step 6], and rolling is performed at a rolling ratio of 80% or more to obtain a thin plate.

Further, an intermediate annealing is performed for 5 seconds to 20 hours at a temperature at which a portion of the thin plate is recrystallized, that is, a temperature of 400 ° C or higher and 700 ° C or lower [Step 7], and thereafter, after heating to 100 ° C or higher and 400 ° C or lower, At the temperature, the intermediate plate is rolled to a medium temperature of 5% or more and 50% or less. Inter-temperature rolling [Step 8].

Thereafter, an intermediate solution heat treatment for resolubilizing the solute atoms is carried out [Step 9]. In the recrystallized aggregate structure of the thin plate in the intermediate solution heat treatment, the cubic azimuth area ratio is increased.

After the intermediate solution heat treatment [Step 9], the aging precipitation heat treatment [Step 10], the final cold rolling [Step 11], and the tempering annealing [Step 12] are sequentially performed.

On the other hand, the prior method for producing a precipitated copper alloy is a method of casting a copper alloy raw material [Step 1] to obtain an ingot, and performing homogenization heat treatment [Step 2], followed by hot pressing in sequence. [Thin 3], cooling (water bath cooling) [Step 4], end face cutting [Step 5], and cold rolling [Step 6] are thinned. And performing an intermediate solution heat treatment in a temperature range of 700 ° C or more and 1000 ° C or less [Step 9] to resolubilize the solute atoms, followed by aging precipitation heat treatment [Step 10], final cold rolling [Step 11], and optionally Quenching and tempering [Step 12] meets the necessary strength. In the series of steps described above, the aggregate structure of the material is roughly determined by the recrystallization generated in the intermediate solution heat treatment, and the final decision is made by the rotation of the orientation generated in the final calendering.

Compared with the manufacturing method of the present invention, the above two steps of the intermediate annealing [Step 7] and the intermediate temperature rolling [Step 8] have not been previously performed.

Next, an embodiment in which the conditions of each step in the manufacturing method of the present invention are set in more detail will be described.

In the casting [Step 1], at least 1.0% by mass or more and 5.0% by mass or less of Ni is contained, and 0.1% by mass or more and 1.0% by mass or less of Si is contained, and the other sub-additive elements are blended as appropriate, as needed. And The alloy raw material composed of Cu and unavoidable impurities is melted in a high-frequency melting furnace, and is cooled at a cooling rate of 0.1 ° C / s or more and 100 ° C / s or less to obtain an ingot. Further, the ingot is subjected to a homogenization heat treatment for 3 minutes to 10 hours at 800 ° C or more and 1020 ° C or less [Step 2]. Thereafter, hot rolling is performed [Step 3], and further water quenching (corresponding to cooling [Step 4]). And the end face is cut [Step 5] to remove the oxide film. Thereafter, a cold rolling having a rolling ratio of 80% to 99.8% is carried out [Step 6] to obtain a thin plate.

Then, the intermediate annealing is performed at 400 ° C or higher and 700 ° C or lower for 5 seconds to 20 hours [Step 7], and further, after heating at 100 ° C or higher and 400 ° C or lower, the rolling ratio is 5% at this temperature. Intermediate temperature rolling of 50% or less above [Step 8]. Here, the term "warm rolling" means rolling at a temperature of from 100 ° C to 400 ° C.

Thereafter, an intermediate solution heat treatment is performed for 5 seconds to 1 hour at 600 ° C or more and 1000 ° C or less [Step 9]. Thereafter, the copper alloy sheet material of the present invention is preferably obtained by sequentially performing the following steps: aging precipitation heat treatment at 400 ° C or more and 700 ° C or less and 5 minutes to 10 hours in an inert gas atmosphere such as nitrogen or argon [Step 10] The final cold rolling is performed at a rolling ratio of 3% or more and 25% or less [Step 11], and tempering annealing at 200 ° C or higher and 600 ° C or lower for 5 seconds or longer and 10 hours or shorter [Step 12].

In the manufacturing method of the present invention, when there is no particular need for the properties of the obtained sheet material, the end surface cutting [Step 5], the final cold rolling [Step 11], and the tempering annealing step may be omitted. 12] One or more of each step.

In this embodiment, in the hot rolling [Step 3], the temperature is above 700 ° C. In the temperature zone below the thermal temperature (1020 ° C), the following processing is performed: a process for destroying a cast structure or segregation to form a uniform structure, and a process for refining crystal grains generated by dynamic recrystallization.

In the intermediate annealing [Step 7], heat treatment is performed to such an extent that the entire surface of the structure in the alloy is not recrystallized. Thereafter, the temperature band which is heated to prevent recrystallization is preferably 100 ° C or more and 400 ° C or less, more preferably 120 ° C or more and 380 ° C or less, and particularly preferably 140 ° C or more and 360 ° C or less, at which temperature, Preferably, the pressure is 5% or more and 50% or less, more preferably 7% or more and 45% or less, and particularly preferably, the intermediate temperature rolling is performed at a rolling ratio of 10% or more and 40% or less [Step 8], and the introduction of the processing strain is controlled. freed.

If the rolling ratio in the intermediate temperature-calendering [Step 8] is too low, the processing strain is small, and in the intermediate solution heat treatment in the subsequent step [Step 9], the crystal grains are coarsened, the bending wrinkles become large, and the characteristics are poor. . On the other hand, if the rolling ratio in the intermediate temperature rolling [Step 8] is too high, the cubic azimuth which is grown in the recrystallization solution heat treatment [Step 9] is rotated to another orientation, and the cubic azimuth area ratio is lowered. Further, in the case where the heating temperature in the intermediate temperature rolling [Step 8] is lower than 100 ° C, the release of the processing strain becomes less, and conversely, when the heating temperature is higher than 400 ° C, the processing strain is released, and further Crystallization, in the intermediate solution heat treatment in the subsequent step [Step 9], the dispersibility of the cubic orientation crystal grains in the strain-induced grain boundary migration becomes insufficient. As a result, when the heating temperature in the intermediate temperature rolling [Step 8] is too high or too low, the bending anisotropy or the proofing stress as the anisotropy of the strength is generated. Anisotropy.

In the intermediate solution heat treatment [Step 9], in the recrystallized aggregate structure, The cubic azimuth area ratio increases. Here, if the heat treatment temperature of the intermediate annealing [Step 7] before the intermediate solution heat treatment [Step 9] is higher than the above range, it is not preferable to form an oxide film. Therefore, it is preferable to set the heat treatment temperature in the intermediate annealing [Step 7] to 400 ° C or more and 700 ° C or less. In particular, although it is difficult to determine without distinction, the cubic azimuthal area ratio tends to increase in the intermediate solution heat treatment [Step 9] because the heat treatment temperature is set to the above temperature range in the intermediate annealing [Step 7].

After the intermediate solution heat treatment [Step 9], the aging precipitation heat treatment [Step 10], the final cold rolling [Step 11], and the tempering annealing [Step 12] are carried out. In order to increase the cubic azimuth area ratio generated by strain-induced grain boundary migration in the recrystallized aggregate structure formed in the intermediate solution heat treatment [Step 9], it is effective to perform specific processing in the intermediate temperature rolling [Step 8]. . Moreover, the development of the cubic azimuth grains is facilitated by controlling the crystal orientation in a specific direction in the intermediate temperature rolling [Step 8]. Further, by performing the aging precipitation heat treatment [Step 10], the additive element is precipitated from the solid solution, whereby the mechanical strength can be improved by precipitation strengthening. Further, the plate thickness can be finally adjusted by performing the final cold rolling [Step 11]. Further, the quenching and tempering of the sheet material can be finally adjusted by performing the tempering annealing [Step 12].

Further, further processing strain is introduced by cold rolling [Step 6], and heat treatment is performed in the intermediate annealing [Step 7] at 400 ° C or more and 700 ° C or less for 5 seconds to 20 hours, and further intermediate temperature rolling is performed [Step 8]. Thereby, the cubic azimuth area ratio is remarkably increased in the recrystallized aggregate structure in the intermediate solution treatment [Step 9].

The purpose of the above intermediate annealing [Step 7] is to obtain incomplete recrystallization Instead, the subannealed tissue is partially recrystallized. The intermediate temperature rolling [Step 8] aims to introduce and release microscopically uneven strain by rolling at a heating temperature of 100 ° C or more and 400 ° C or less and a rolling ratio of 5% or more.

By the effect of the intermediate annealing [Step 7] and the intermediate temperature rolling [Step 8], the growth of the cubic azimuth grains in the intermediate solution treatment [Step 9] and the miniaturization and equal dispersion of the cubic azimuth grains can be realized. . In the intermediate temperature rolling [Step 8], the introduction of strain by rolling and the release of strain by heating are performed, and by appropriately controlling the two, the strain-induced crystal of the intermediate solution heat treatment [Step 9] can be improved. The development of cubic azimuth grains in the boundary migration, the miniaturization of cubic azimuth grains, and the like. That is, the cubic azimuth grains can be developed by introducing strain, and the grain size and the isodispersity of the cubic azimuth grains can be improved by releasing the strain. In the conventional method, the heat treatment such as the intermediate solution treatment [Step 9] is mainly for the purpose of reducing the load in the subsequent step to recrystallize the material to reduce the strength, but in the present invention and the purpose is completely different.

The thickness of the copper alloy sheet of the present invention is not particularly limited and is usually 0.03 to 0.50 mm, preferably 0.05 to 0.35 mm.

The copper alloy sheet material of the present invention preferably satisfies and has, for example, the following characteristics required for a copper alloy sheet for a connector by satisfying the above-described respective requirements.

The bending workability of one of the characteristics is preferably such that no crack is formed in the curved surface portion in the 180° close U bending test. The detailed conditions are as described in the examples.

The bending coefficient of one of the characteristics is preferably 130 GPa or less. The detailed conditions are as described in the examples. The lower limit of the bending coefficient exhibited by the copper alloy sheet of the present invention is not particularly limited and is usually 90 GPa or more.

The guaranteed stress of one of the characteristics is preferably 700 MPa or more. Further, it is preferably 750 MPa or more. The detailed measurement conditions are as described in the examples. The upper limit of the guaranteed stress exhibited by the copper alloy sheet of the present invention is not particularly limited, and is usually 900 MPa or less.

The conductivity of one of the characteristics is preferably 5% IACS (International Annealed Copper Standard) or more. Further preferably, it is 10% IACS or more, and particularly preferably 20% IACS or more. The detailed measurement conditions are as described in the examples. The upper limit of the conductivity of the copper alloy sheet of the present invention is not particularly limited and is usually 50% IACS or less.

[Examples]

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

(Examples 1 to 14 and Comparative Examples 1 to 4)

The alloy containing the respective amounts of Ni, Si, and sub-addition elements shown in Table 1, and the remainder consisting of Cu and unavoidable impurities was melted in a high-frequency melting furnace, and was applied at 0.1 ° C / sec. The casting was carried out by cooling at a cooling rate of 100 ° C / sec [Step 1], and an ingot was obtained.

The ingot is subjected to a homogenization heat treatment for 3 minutes to 10 hours at 800 ° C or higher and 1020 ° C or lower [Step 2], and then subjected to hot rolling as a hot working at 700 ° C or higher and at a reheating temperature (1020 ° C) or less. 3] Further, water quenching (corresponding to cooling [Step 4]) is performed to obtain a hot rolled sheet. Then, The end face of the hot rolled sheet is cut [Step 5] to remove the oxide film. Thereafter, cold rolling is performed at a calendering rate of 80% to 99.8% [Step 6] to obtain a sheet.

Then, the intermediate annealing of the thin plate is carried out by heat treatment at 400 ° C to 700 ° C for 5 seconds to 20 hours [Step 7], and further, after heating to 100 ° C or higher and 400 ° C or lower, at a temperature of 5% or more. And the rolling rate of 50% or less is subjected to calendering intermediate temperature rolling [Step 8].

Thereafter, the intermediate solution treatment is carried out at 600 ° C. or higher and 1000 ° C or lower for 5 seconds to 1 hour [Step 9]. Then, the aging precipitation heat treatment is performed in an inert gas atmosphere at 400 ° C or more and 700 ° C or less for 5 minutes to 1 hour [Step 10], and the final cold rolling is performed at a rolling ratio of 3% to 25% [Step 11], and The quenching and tempering of 5 seconds or more and 10 hours or less was carried out at 200 ° C or more and 600 ° C or less [Step 12], and the test materials of the copper alloy sheets (Examples 1 to 14 and Comparative Examples 1 to 4) were produced. The final thickness of each test piece was set to 0.08 mm.

The compositions and characteristics of the above Examples 1 to 14 and Comparative Examples 1 to 4 are shown in Tables 1 and 2.

Further, after each heat treatment or rolling, pickling or surface grinding is performed depending on the state of oxidation or roughness of the surface of the material, and the shape is subjected to correction by a tension leveler. Further, the processing temperature in the hot working [Step 3] is measured by a radiation thermometer provided on the feeding side and the discharging side of the calender.

The following characteristics were investigated for each test material.

(a) cubic azimuth area ratio

The measurement area of 0.09 mm ² (300 μm × 300 μm) was measured by the EBSD method under the condition that the scanning step was 0.1 μm. Further, in the measurement area, 60 μm × 60 μm was used as one block, and a total of 25 blocks (5 blocks × 5 blocks) were measured in one field of view. In this case, the scanning step is set to a step of 0.1 μm as described above in order to measure fine crystal grains. In the analysis, the EBSD measurement result in the measurement area of 300 μm × 300 μm was divided into the above 25 blocks, and the cubic azimuth area ratio, the average crystal grain area, the number of crystal grains, and the mother containing the cubic azimuth were confirmed. The average grain area of the material. The electron beam system uses hot electrons from a tungsten filament of a scanning electron microscope as a generation source.

(b) 180° close U bending test

The processing was performed by press-pressing so that the width was 0.25 mm perpendicular to the rolling direction and the length was 1.5 mm. The bending axis is set to GW (Good Way) so that the bending is performed at a right angle to the rolling direction, and the B bending (Bad Way) is performed so as to be parallel to the rolling direction. After the 90 °W bending process was performed by the JCBA-T307 (2007), the technical standard of the Japan Copper Association, a 180° close bending process was performed without using the inner radius of the compression tester. The curved surface was observed using a scanning electron microscope at 100 times to investigate the presence or absence of cracks. The person without cracks is indicated as "○ (good)", and the person with cracks is indicated as "× (poor)". Regarding the size of the crack here, the maximum width is 30 μm to 100 μm, and the maximum depth is 10 μm or more.

(c) bending factor

The test piece has a width of 0.25 mm perpendicular to the rolling direction and is parallel to the pressure. The length of the extension is 1.5 mm by means of press stamping. The front and back sides of the test piece were measured 10 times with a cantilever beam, and the average value thereof was shown.

The bending coefficient E (GPa) is represented by the following formula (1).

E=4a/b×(L/t) ³ (1)

Here, a is the slope of the displacement f and the stress w, b is the width of the test material, L is the distance between the fixed end and the load point, and t is the thickness of the test piece.

In this test, it was confirmed that the deformation was in the direction parallel to the rolling parallel direction and the rolling perpendicular direction.

(d) Guaranteed stress [Y]

In the measurement of the bending coefficient, the guaranteed stress Y (MPa) is calculated from the indentation amount (displacement) up to the elastic limit of each test piece according to the following formula (2).

Y={(3E/2)×t×(f/L)×1000}/L (2)

E is the bending coefficient, t is the plate thickness, L is the distance between the fixed end and the load point, and f is the displacement (pressing depth).

In this test, it was confirmed that the stress was anisotropy in the direction parallel to the rolling and the direction perpendicular to the rolling.

(e) Conductivity [EC]

The specific resistance was measured by a four-terminal method in a thermostatic chamber maintained at 20 ° C (± 0.5 ° C) to calculate the electrical conductivity. Furthermore, the distance between the terminals was set to 100 mm.

With respect to Examples 1 to 14 and Comparative Examples 1 to 4 of the present invention, the main raw materials Cu, Ni, Si, and the sub-additive elements were blended and melted in such a manner as to have the composition shown in Table 1. Casting.

As shown in Table 2, under the production conditions of Examples 1 to 14, the intermediate temperature rolling [Step 8] was performed after heating to 100 ° C or more and 400 ° C or less, and the rolling ratio was set to 5% or more. On the organization, Examples 1 to 14 Example embodiments of a cubic orientation of an area of 5% or 50% or less, the average grain area of crystal grains of the cube orientation is 1.8 m ² or less than ² 45.0μm, per 1 block (60μm × 60μm The number of cubic azimuth grains is 40 or more and 100 or less, and the average crystal grain size of the base material containing cubic azimuth particles is 50 μm ² or less. Among the characteristics of Examples 1 to 14, the 180° U close bending, the bending anisotropy, and the proof stress anisotropy all showed excellent results.

In Comparative Example 1 to Comparative Example 4, since the specification in the production method of the present invention was not satisfied, the case where the cubic azimuth area ratio and the number of cubic azimuth particles per block were not satisfied was shown.

As shown in Tables 1 and 2, the characteristics of the bending, the characteristics of the bending coefficient, and the characteristics of the guaranteed stress are all good when the range of the present invention is satisfied as follows: Ni is contained in an amount of 1.0% by mass or more and 5.0% by mass or less, 0.1% by mass or less. The above-mentioned 2.0 mass% or less of Si and, if necessary, 0.005 mass% or more and 1.0 mass% or less in total, are selected from the group consisting of Sn, Zn, Ag, Mn, B, P, Mg, Cr, Zr, Fe, and Hf. At least one kind, and the remainder is composed of copper and unavoidable impurities. In the crystal orientation analysis by the electron backscatter diffraction method, the area ratio of the cubic orientation {001}<100> is 5% or more and 50% or less. addition to those preferred orientation of cubic grains having an average grain area of 1.8 m ² or less than ² 45.0μm, and thus the average grain area of crystal grains of the base material is 50 m ² or less. In the bending characteristics, cracks are not generated at the top of the bend. Further, among the characteristics of the bending coefficient, the bending coefficient anisotropy is within 10 GPa, and in the characteristic of the guaranteed stress, the stress anisotropy is ensured to be within 10 MPa, and the anisotropy is small.

Therefore, the copper alloy sheet material of the present invention can provide a copper alloy sheet material suitable for a lead frame, a connector, a terminal material, and the like for electric and electronic equipment, and a connector or a terminal material, a relay, a switch, or the like for an automobile.

Further, as shown in Table 2, in the samples of the comparative examples, the results were inferior in any of the characteristics.

That is, since the average crystal grain size of the cubic azimuth crystal grains of Comparative Examples 1, 2, and 4 is too large, the BW has a bending property and a bending coefficient anisotropy, and the stress anisotropy is poor. Since the cubic azimuth area ratio of Comparative Example 3 is too small, the bending characteristics (GW, BW) and the bending anisotropy are ensured, and the stress anisotropy is poor.

Furthermore, the conductivity is shown to be 30 to 45% IACS.

(previous example)

The alloy composition described in Table 3 below (the remainder being copper (Cu)) was subjected to intermediate annealing [Step 7] and intermediate temperature rolling [Step 8], except that the same as in the above Example 1 was carried out. The way to make copper alloy sheets. The test materials of the copper alloy sheets obtained as a result were evaluated in the same manner as in the above Example 1. The results are shown in Table 4.

As can be seen from Tables 3 and 4, the prior examples 1 and 2 which were not satisfied with the alloy composition specified in the present invention and which were not subjected to the intermediate annealing [Step 7] and were not heated by the intermediate temperature rolling [Step 8] thereafter. For the copper alloy sheet, even if the manufacturing conditions (each step and condition) other than the two steps are adopted, the average grain area of the cube orientation of either one is larger, and the number of cubes per block is less. And the bending coefficient and the anisotropy of the guaranteed stress become larger.

Further, although the alloy composition of the present invention is satisfied, the copper alloy sheet of the prior art 3 which has not been subjected to the intermediate annealing [Step 7] and has not been heated by the intermediate temperature rolling [Step 8] thereafter, even if The manufacturing conditions (each step and condition) other than the two steps, the average grain area of the cube orientation of any one of the blocks is large, and the number of cubic particles per block is small, and the bending property (BW) Poor, and the anisotropy of the bending coefficient and the guaranteed stress becomes large.

Unlike these, regarding the copper alloy sheet produced by the previous manufacturing conditions, in order to clarify the difference from the copper alloy sheet of the present invention, a copper alloy sheet is produced under the previous manufacturing conditions, and the same characteristic items as described above are performed. Evaluation. In addition, unless otherwise indicated, the thickness of each plate material is adjusted so that it may become the same thickness as the above-mentioned Example.

(Comparative Example 101). . . Japanese Laid-Open Patent Publication No. 2011-162848, the conditions of the present invention

A copper alloy composed of 3.2% by mass of Ni, 0.7% by mass of Si, 1.0% by mass of Zn, and 0.2% by mass of Sn was melted and cast. The end face of the obtained ingot is cut, and after the homogenization heat treatment, the calendering is performed at a temperature of 550 to 850 ° C, and is cooled by a water bath. After quenching, the oxide layer of the surface layer is removed by mechanical grinding (end face cutting). Then, after rolling to a specific thickness by cold rolling, it is further cold-rolled at a processing ratio of 90% or more, and heated to a temperature of 800 to 900 ° C at a temperature increase rate of 0.1 ° C / s or less to carry out a solution treatment.

Then, aging treatment was carried out at 500 °C. The aging treatment time is adjusted to the time when the hardness becomes a peak at the temperature of 460 ° C depending on the composition of the copper alloy. Further, regarding the aging treatment time, the optimum aging treatment time was determined by preliminary experiments according to the alloy composition of Example 1 of the present invention.

Then, the aging-treated sheet was further subjected to final cold rolling at a rolling ratio of 40%. Further, low temperature annealing was performed at 480 ° C for 30 seconds. Furthermore, the grinding and the end face cutting were performed in the middle as needed, and the plate thickness was unified to 0.10 mm.

This was set as sample c01.

The obtained test body c01 is not subjected to intermediate annealing in the production conditions as compared with the above-described embodiment of the present invention [Step 7], and the intermediate temperature rolling at the heating temperature before the solution heat treatment [Step 9] is not performed. 8]. Further, since the temperature increase rate of the solution heat treatment is slow, the grain growth becomes remarkable near the reaching temperature, and the crystal grains are coarsened. The area of the cubic azimuth grains of the obtained structure is more than 150 μm ² or more. Further, the anisotropy of the bending coefficient and the strength is also larger than 10 GPa and more than 15 MPa, respectively, and the result is that the characteristics required in the present invention are not satisfied.

(Comparative Example 102). . . The conditions of the first embodiment and the fourth embodiment of the Japanese Patent Laid-Open Publication No. 2011-12321

Copper composed of 2.8% by mass of Ni and 0.9% by mass of Si Alloy (Example 1 of the publication) and a copper alloy composed of 2.8% by mass of Ni, 0.9% by mass of Si, 0.1% by mass of Zn, 0.1% by mass of Mg, and 0.1% by mass of Sn (this publication) Each of the alloys of Example 4) was melted in a coreless furnace (high frequency induction melting furnace) under charcoal coating, and cast in a mold surrounded by a copper mold at four sides to have a thickness of 250 mm and a width of 620 mm. Ingots with a length of 2500 mm.

Then, at the intersection of the position of the mold 155 mm and the position of the thickness of 125 mm, the diameter is A 3 mm SUS rod was inserted from the upper surface of the upper end of the mold in the vertical direction and the depth of the unsolidified portion was measured. The value obtained by subtracting the length of the mold (length of the copper mold) from the obtained depth of the unsolidified portion is defined as the distance from the depth from the lower end of the mold to the depth at which the solidification ends. Specifically, it is 300 mm (Example 1 of the publication) and 260 mm (Example 4 of the publication). The ingot is obtained by adjusting the casting speed in the range of 50 to 200 mm/min so that the distance becomes 250 mm or more.

A 250 × 620 × 300 mm block of the obtained ingot was cut and fixed, and a section (250 × 15 × 300 mm) of a casting direction and a parallel section was taken from a central portion having a width of 620 mm. The giant structure obtained by immersing it in nitric acid for 0.5 to 1 hour and etching is obtained in the [100] axis direction of the columnar crystal. The angle at which the plane orthogonal to the casting direction intersects with the [100] axis direction of the columnar crystal is measured. Specifically, it is 13° (Example 1 of the publication) and 11° (Example 4 of the publication).

Further, after the ingot is homogenized, the temperature is adjusted to 500 to 1000 ° C, and the total processing ratio is 60 to 96%, and then the obtained rolled material is directly subjected to water bath cooling to have a thickness of about 10mm The coil. The surface of the rolled material is ground to remove scale. The cubic azimuth ratio of the rolled material at this time point is set to 5 to 95%. Thereafter, in the order described, the processing rate is 85 to 99.8% cold rolling, and the solution heat treatment is performed at 700 to 1020 ° C for 5 seconds to 1 hour, and the processing rate is 1 to 6.0% of the final cold rolling, at 200~ The quenching and tempering was performed at 600 ° C for 5 seconds to 10 hours to obtain a test material having a thickness of 0.15 mm.

These were respectively referred to as sample d01 (Example 1 of the publication) and d02 (Example 4 of the publication).

The obtained test bodies d01 and d02 were not subjected to intermediate annealing in the production conditions as compared with the above-described examples of the present invention [Step 7], and the intermediate temperature rolling at the heating temperature before the solution heat treatment [Step 9] was not performed. [Step 8]. Regarding the area ratio of the cubic azimuth grains of the obtained structure, the sample d01 (Example 1 of the publication) was 35% and the sample d02 (Example 4 of the publication) was 7%, and the grain growth was changed. It is apparent that the average crystal grain area of the base material containing the cubic orientation crystal grains is coarse, and the sample d01 (Example 1 of the publication) is 254 μm ² and the sample d02 (Example 4 of the publication) is 201 μm ^{2 .} . Further, the anisotropy of the bending coefficient and the strength is also large, and is more than 10 GPa and more than 15 MPa, respectively, which is a result of not satisfying the required characteristics in the present invention.

The present invention is not limited to the details of the present invention, and is not intended to limit the invention, and is not intended to be inconsistent with the scope of the invention. Under the spirit and scope, the maximum scope should be explained.

The present application claims priority based on Japanese Patent Application No. 2011-102996, filed on Jan. Addition is part of the description of this manual.

Fig. 1 is a view for explaining the dispersibility in the case where four adjacent blocks are one group and at least four groups are used.

Claims (8)

A copper alloy sheet material having a composition containing 1.0% by mass or more and 5.0% by mass or less of Ni, 0.1% by mass or more and 2.0% by mass or less of Si, and the remainder being composed of copper and unavoidable impurities; In the crystal orientation analysis of the Electron Back Scatter Diffraction, the area ratio of the crystal grains having an orientation within 15° from the cubic orientation {001}<100> is 5% or more and 50% or less, and has a self-supporting state. The grain in which the square orientation {001}<100> is shifted within 15° is dispersed in 40 or more and 100 or less in 60 μm square. The scope of the patent copper alloy sheet material of item 1, wherein the side having self-orientation {001} <100> of the average grain area of crystal grains of less than 15 ° Azimuth is 1.8 m ² or less than ² 45.0μm. A copper alloy sheet material having a composition containing 1.0% by mass or more and 5.0% by mass or less of Ni, 0.1% by mass or more and 2.0% by mass or less of Si, and a total of 0.005% by mass or more and 1.0% by mass or less selected from the group consisting of Sn and Zn. At least one of a group consisting of Ag, Mn, B, P, Mg, Cr, Zr, Fe, and Hf, and the remainder consisting of copper and unavoidable impurities; and utilizing an electron backscatter diffraction method In the crystal orientation analysis, the area ratio of the crystal grains having an orientation within 15° from the cubic orientation {001}<100> is 5% or more and 50% or less, and has a shift of 15° from the cubic orientation {001}<100>. The crystal grains within the orientation are dispersed in 40 or more and 100 or less in 60 μm square. The patentable scope of application of the copper alloy sheet material of item 3, wherein the standing side having orientation {001} <100> of the average grain area of crystal grains of 15 ° shifted position within 1.8 m ² or more is ² or less 45.0μm. The copper alloy sheet material according to any one of claims 1 to 4, wherein the crystal grains of the base material have an average crystal grain size of 50 μm ² or less. The copper alloy sheet material according to any one of claims 1 to 4, wherein a difference between a bending coefficient in a rolling parallel direction and a bending coefficient in a rolling vertical direction is 10 GPa or less in absolute value, and a guaranteed stress in a rolling parallel direction is The difference in the guaranteed stress in the rolling vertical direction is 10 MPa or less in absolute value. For example, in the copper alloy sheet of claim 5, wherein the difference between the bending coefficient in the parallel direction of rolling and the bending coefficient in the vertical direction of rolling is 10 GPa or less in absolute value, and the guaranteed stress in the parallel direction of rolling and the guaranteed stress in the vertical direction of rolling The difference is 10 MPa or less in absolute value. A method for producing a copper alloy sheet, which performs homogenization heat treatment and hot rolling on an ingot obtained by casting a copper alloy material, and further forms a thin plate by cold rolling, and then re-solidifies the solute atoms in the sheet. Intermediate solution heat treatment; the copper alloy raw material is composed of an alloy of a copper alloy plate material according to claim 1 or 3; the method for manufacturing the copper alloy plate comprises the following steps in sequence: above 800 ° C The homogenization heat treatment is carried out at 1020 ° C or lower for 3 minutes to 10 hours, and after the cold rolling is performed at a rolling ratio of 80% or more and 99.8% or less, the temperature is not more than the recrystallization temperature, that is, 400 ° C or more and 700 ° C or less for 5 seconds to 20 seconds. Intermediate annealing in hours, Further, after heating to 100° C. or higher and 400° C. or lower, the calendering rate is 5% or more and 50% or less at the intermediate temperature, and then the intermediate solution is performed at 600° C. or more and 1000° C. or less for 5 seconds to 1 hour. The heat treatment is performed at 400 ° C or more and 700 ° C or less for 5 minutes to 10 hours.