JP5261122B2 - Copper alloy sheet and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a Cu-Ni-Si based copper alloy sheet having little anisotropy while holding high strength of &ge;700 MPa tensile strength and excellent bending workability, and a method for manufacturing therefor. <P>SOLUTION: The copper alloy sheet includes the composition composed, by mass%, of 0.7-4% Ni, 0.2-1.0% Si and if necessary, one or more of 0.1-1.2% Sn, &le;2.0% Zn, and &le;1.0% Mg, and furthermore, &le;3% total of one or more elements selected from group composed of Co, Cr, B, P, Fe, Zr, Ti, Mn, Ag, Be and misch metal and the balance Cu with inevitable impurities. In the copper alloy sheet, in the case of being an integral intensity of ähkl} diffraction peak when an X-ray diffraction is applied on the sheet surface, is Iähkl}, this copper alloy sheet includes a crystal orientation satisfying Iä200}/Iä422}&ge;15. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a copper alloy sheet and a manufacturing method thereof, and relates to a Cu—Ni—Si based copper alloy sheet used for electrical and electronic parts such as connectors, lead frames, relays, and switches, and a manufacturing method thereof.

  Materials used for electrical and electronic parts as current-carrying parts such as connectors, lead frames, relays, and switches are required to have good conductivity in order to suppress the generation of Joule heat due to current conduction. High strength is required to withstand the stress applied at the time and during operation. In addition, since electrical and electronic parts such as connectors are generally formed by bending after press punching, excellent bending workability is also required.

  In recent years, electrical and electronic parts such as connectors tend to be highly integrated, miniaturized, and lightened, and accordingly, there is an increasing demand for thinning of copper and copper alloy plate materials. For this reason, the strength level required for the material is becoming stricter. However, in general, there is a trade-off relationship between the strength and conductivity of the copper alloy sheet and the strength and bending workability, and it is difficult to obtain a copper alloy sheet that satisfies these simultaneously. . Among such copper alloy sheet materials, a Cu—Ni—Si-based alloy (so-called Corson alloy) has attracted attention as a material that is relatively excellent in the property balance between strength and conductivity. For example, Cu—Ni—Si based copper alloy sheet material has a relatively high conductivity (30 to 50% IACS) by processes based on solution treatment, cold rolling, aging treatment, finish cold rolling and low temperature annealing. The strength of 700 MPa or more can be achieved while maintaining the above. However, since Cu—Ni—Si based copper alloy sheet has high strength, its bending workability is not always good.

  Further, a general copper alloy sheet produced through a rolling process has fibrous crystal grains extending in the LD (rolling direction), and further, the LD is used as a bending axis due to the influence of the anisotropy of the texture. It is known that the characteristics differ greatly between the bad way bending and the good way bending with TD (direction perpendicular to the rolling direction and the plate thickness direction) as the bending axis. However, in electrical and electronic parts such as connectors, this anisotropy is a problem because the plate material is formed by bending both GoodWay and BadWay. Cu-Ni-Si based copper alloy Boards are no exception.

Various methods for improving the bending workability by controlling the crystal orientation (texture) have been proposed as a method for improving such a bending workability problem in the Cu—Ni—Si based copper alloy sheet. . For example, if the X-ray diffraction intensity of the {hkl} plane is I {hkl}, (I {111} + I {311}) / I {220} ≦ 2.0
And satisfying the method of improving the workability of GoodWay (see, for example, Patent Document 1) and (I {111} + I {311}) / I {220}> 2.0, A method (for example, refer to Patent Document 2) for improving the bending workability of BadWay has been proposed. Further, in a material having a face-centered cubic lattice such as copper, measurement by the SEM-EBSP method is performed using the Cube orientation {001} <100>, which is generally known as one of recrystallization textures. As a result, a method has been proposed for improving the bending workability of a Cu—Ni—Si based copper alloy sheet so as to have a texture where the ratio of the Cube orientation {001} <100> is 50% or more (for example, And Patent Document 3). Further, a method for improving the bending workability of the Cu—Ni—Si based copper alloy sheet so as to satisfy (I {200} + I {311}) / I {220} ≧ 0.5 has been proposed ( For example, see Patent Document 4). Further, the X-ray diffraction intensities from the {311} plane, {220} plane, and {200} plane on the plate surface of the Cu—Ni—Si based copper alloy sheet are respectively I {311}, I {220}, and I {200. }, And when the crystal grain size is A (μm), Cu-Ni-Si is satisfied so as to satisfy I {311} × A / (I {311} + I {220} + I {200}) <1.5. A method for improving the bending workability of a copper alloy sheet (for example, see Patent Document 5), and X-ray diffraction of {420} crystal plane and {220} crystal plane on the surface of a Cu-Ni-Si copper alloy sheet When the strength is I {420} and I {220}, respectively, bending of the Cu—Ni—Si based copper alloy sheet so as to satisfy 0.1 ≦ I {420} / I {220} ≦ 0.5 For improving the performance (for example, see Patent Document 6) ) Has also been proposed.

Japanese Patent Laying-Open No. 2006-9108 (paragraph numbers 0007-0009) JP 2006-16629 A (paragraph numbers 0008-0009) JP 2006-152392 A (paragraph numbers 0020-0021) JP 2000-80428 A (paragraph numbers 0003-0004) JP 2006-9137 A (paragraph numbers 0007-0008) Japanese Patent Laying-Open No. 2008-38231 (paragraph numbers 0011-0012)

However, in the method of Patent Document 1, (I {111} + I {311}) / I {220} ≦ 2.0 as a condition for improving GoodWay bending workability.
In contrast, the method of Patent Document 2 satisfies (I {111} + I {311}) / I {220}> 2.0 as a condition for improving BadWay bending workability. The conditions for improving GoodWay bending workability and the conditions for improving BadWay bending workability are contradictory conditions.

  In the method of Patent Document 3, it is necessary to perform strong rolling at a rolling rate of 95% or more before solution treatment in order to develop the Cube orientation. There is also the above problem.

Further, in the method of Patent Document 4, it is necessary to reduce {220} which is a rolling texture in order to satisfy (I {200} + I {311}) / I {220} ≧ 0.5. Therefore, there is a problem that the finish rolling rate cannot be increased. In the Cu—Ni—Si based copper alloy sheet, since the strength is increased by utilizing dislocations around the Ni ₂ Si precipitates, there is a problem that a decrease in the finish rolling ratio directly leads to a decrease in strength.

Further, in the methods of Patent Documents 5 and 6, the intensity of the diffraction peak measured when the most common X-ray diffractometer using copper as a tube is used as the bending workability improvement condition by controlling the crystal orientation. That is, {111}, {200}, {220}, {311}, {331}, and {420} appearing at a diffraction angle 2θ <180 °. Further, the intensity of the diffraction peak located on the wide angle side is weak, and I {331} is I {111} even in the case of random orientation.
Therefore, the wide-angle peak is ignored, and only the four low-angle peaks {111}, {200}, {220}, and {311} are often discussed.

  Therefore, it is not necessary to perform strong rolling before the solution treatment, and even if finish rolling is performed at a high rolling rate, Cu having a high tensile strength of 700 MPa or more without deteriorating any bending workability of GoodWay or BadWay. Development of a Ni-Si based copper alloy sheet has been desired. However, as described above, no matter how the main diffraction peaks that can be measured by X-ray diffraction of a copper tube are combined, it has been impossible to find a crystal orientation control technique that improves such bending workability.

  Therefore, in view of such a conventional problem, the present invention is a Cu-Ni-Si-based copper alloy having excellent bending workability with low anisotropy while maintaining a high strength of 700 MPa or more. It aims at providing a board | plate material and its manufacturing method.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors contain 0.7 to 4% by mass of Ni and 0.2 to 1.0% by mass of Si, with the balance being Cu and inevitable impurities. In a copper alloy sheet having a composition, when the integrated intensity of the {hkl} diffraction peak when X-ray diffraction is performed on the plate surface is I {hkl}, the crystal orientation satisfies I {200} / I {422} ≧ 15 It is possible to produce a Cu-Ni-Si-based copper alloy sheet having a low anisotropy and an excellent bending workability while maintaining a high strength of a tensile strength of 700 MPa or more. The headline and the present invention were completed.

  That is, the copper alloy sheet according to the present invention has a composition containing 0.7 to 4% by mass of Ni and 0.2 to 1.0% by mass of Si, with the balance being Cu and inevitable impurities. When the integrated intensity of the {hkl} diffraction peak when X-ray diffraction is performed is I {hkl}, the crystal orientation satisfies I {200} / I {422} ≧ 15.

  The copper alloy sheet may have a composition further including one or more of 0.1 to 1.2 mass% of Sn, 2.0 mass% or less of Zn, and 1.0 mass% or less of Mg. In addition, the copper alloy sheet further includes at least one element selected from the group consisting of Co, Cr, B, P, Fe, Zr, Ti, Mn, Ag, Be, and Misch metal in a total range of 3% by mass or less. You may have the composition which contains. The copper alloy sheet preferably has a tensile strength of 700 MPa or more. Further, when the copper alloy sheet has a tensile strength of 800 MPa or more, it preferably has a crystal orientation satisfying I {200} / I {422} ≧ 50.

  A method for producing a copper alloy sheet according to the present invention includes a raw material for a copper alloy having a composition containing 0.7 to 4% by mass of Ni and 0.2 to 1.0% by mass of Si, with the balance being Cu and inevitable impurities. A melting and casting step for melting and casting, a hot rolling step for performing hot rolling while lowering the temperature from 950 ° C. to 600 ° C. after the melting and casting step, and a rolling rate of 80 after the hot rolling step. The first cold rolling process in which cold rolling is performed at a temperature of at least%, the heat treatment process in which heat treatment is performed at a heating temperature of 500 to 600 ° C. after the first cold rolling process, and the rolling rate is 80% after the heat treatment process. The 2nd cold rolling process which performs cold rolling above, the solution treatment process which performs solution treatment at 700-980 ° C after this 2nd cold rolling process, and rolling after this solution treatment process Intermediate cold performing intermediate cold rolling at a rate of 0-50% An aging treatment step of performing an aging treatment at 400 to 600 ° C. after the intermediate cold rolling step, and a {422} crystal plane by X-ray diffraction before and after the solution treatment in the solution treatment step The integral intensities of Ib {422} and Ia {422} are set to satisfy Ia {422} / Ib {422} ≦ 1, respectively.

  The copper alloy sheet manufacturing method preferably includes a finish rolling step in which cold rolling is performed at a rolling rate of 50% or less after the aging treatment step, and heat treatment is performed at 150 to 550 ° C. after the finish cold rolling step. It is preferable to include a low-temperature annealing step for performing the above.

  In the method for producing a copper alloy sheet, the copper alloy sheet may be one or more of 0.1 to 1.2 mass% Sn, 2.0 mass% or less Zn, and 1.0 mass% or less Mg. It may have the composition which contains further. In addition, the copper alloy sheet further includes at least one element selected from the group consisting of Co, Cr, B, P, Fe, Zr, Ti, Mn, Ag, Be, and Misch metal in a total range of 3% by mass or less. You may have the composition which contains.

  Furthermore, an electrical / electronic component according to the present invention is characterized by using the above-described copper alloy sheet as a material. The electrical / electronic component is preferably a connector, a lead frame, a relay or a switch.

  According to the present invention, Cu- with excellent anisotropy and excellent bending workability while maintaining a high strength of 700 MPa or more, and particularly with good bending workability of both Good Way and Bad Way. A Ni-Si based copper alloy sheet can be produced.

  The embodiment of the copper alloy sheet material according to the present invention contains 0.7 to 4% by mass of Ni and 0.2 to 1.0% by mass of Si, and optionally 0.1 to 1.2% by mass. % Sn, 2.0% by mass or less of Zn and 1.0% by mass or less of Mg, and if necessary, Co, Cr, B, P, Fe, Zr, Ti, Mn, In a copper alloy sheet having a composition containing one or more elements selected from the group consisting of Ag, Be, and Misch metal in a total amount of 3% by mass or less, with the balance being Cu and inevitable impurities, the plate surface (plate thickness A crystal satisfying I {200} / I {422} ≧ 15, where I {hkl} is the integrated intensity of the {hkl} diffraction peak when X-ray diffraction is performed on a plane perpendicular to the vertical direction (rolled surface). It has an orientation and a tensile strength of 700 MPa or more. In addition, when the tensile strength of this copper alloy sheet is 800 MPa or more, better bending workability is required. Therefore, it is preferable to have a crystal orientation satisfying I {200} / I {422} ≧ 50. . Hereinafter, this copper alloy sheet and its manufacturing method will be described in detail.

  As described above, a crystal that improves the bending workability of both GoodWay and BadWay of a Cu-Ni-Si based copper alloy sheet regardless of the combination of main diffraction peaks that can be measured by X-ray diffraction of a copper tube. I could not find the azimuth control technology. Therefore, the present inventors analyzed a crystal orientation with a shorter lattice spacing using a molybdenum tube whose X-ray wavelength is less than half that of the most common copper tube as an X-ray source. It was.

  As a result, the present inventors may have a recrystallized texture in which the {422} crystal plane remains on the rolled surface due to the solution treatment, and the Cu—Ni—Si based copper alloy may have an aging treatment or It has been found that the volume fraction does not change greatly by rolling. When the bending workability of this orientation was investigated using a single crystal Cu—Ni—Si-based copper alloy sheet, both the GoodWay and BadWay bending workability were other {111}, {200}, {220}. , {311}, {331}, {420} were found to be extremely poor compared to the bending workability. Therefore, in a Cu—Ni—Si based copper alloy sheet with a developed {422} crystal plane, the crystal having this orientation becomes the starting point of cracking, so the volume fraction of the {422} crystal plane is only 10% to 20%. It was also found that deep cracks develop easily even without them. Furthermore, it has also been found that the ratio of remaining {422} crystal planes during the solution treatment can be reduced by the heat treatment before the solution treatment. In addition, in this heat treatment, a recrystallized texture having the {200} crystal plane as one of the main orientation components can be obtained without performing strong rolling before the solution treatment, and a high rolling rate of 30 to 40%. It was also found that even after finish rolling, crystal grains having {200} crystal planes as the main orientation component remain at a specific ratio, and the ratio of {422} crystal planes can be kept low. In addition, the crystal grain having the {200} crystal plane as the main orientation component has a TD of <001> when <010> is directed to the LD, and the presence of this crystal grain provides bending workability with little anisotropy. It was confirmed by a bending test of a single crystal Cu—Ni—Si based copper alloy sheet. As described above, the recrystallization texture having the {200} crystal plane as the main orientation component is left in a specific ratio, and the development of the {422} crystal plane is prevented, thereby reducing anisotropy and excellent bending workability. It was found that a high-strength Cu—Ni—Si-based copper alloy sheet having the following can be produced.

In general, the X-ray diffraction pattern from the plate surface (rolled surface) of a Cu—Ni—Si based copper alloy sheet is the diffraction peaks of four crystal planes {111}, {200}, {220}, and {311}. It is configured. As the rolling reduction in cold rolling increases, the X-ray diffraction intensity of the {220} plane increases relatively, the X-ray diffraction intensity of the {200} plane and the {311} plane decreases, and usually {111} The X-ray diffraction intensity of the surface tends to increase slightly. Since X-ray diffraction from other crystal planes is diffraction on the wide angle side, its intensity is small, and I {422}: I {200} = 1: 9 in a random orientation state, that is, I {200} /
I {422} = 9. However, when a Cu—Ni—Si-based copper alloy sheet having a normal composition is obtained by a normal manufacturing process, I {200} / I {422} = 2 to 5 is low, which is a starting point of cracking during bending. It can be seen that the existence ratio of the {422} plane is high.

  In the embodiment of the copper alloy sheet according to the present invention, the {200} plane is one of the main orientation components so that I {200} / I {422} ≧ 15, and the volume fraction of the {422} plane is A reduced rolling texture is realized, and this significantly improves the bending workability of both Good Way and Bad Way. The mechanism for improving the bending workability is considered as follows in a simplified system. When a rolling texture material having a {422} <111> in LD such as copper is evaluated using a Schmid factor, which is an index of the activity of a slip system, it is 0.27, which is almost the lower limit in the low index direction. In addition, in the case of 6 out of 12 combinations of “slip surface, slip direction”, since it is orthogonal to the LD, it does not contribute to deformation. Further, the TD of this copper alloy sheet is {422} <011> and the Schmitt factor is 0.41, but in 8 cases out of 12 combinations of “slip surface, slip direction”, TD and It is orthogonal and does not contribute to deformation. Such a crystal grain having a {422} crystal face on the rolled face is likely to generate a shear band due to an external force in both LD and TD and easily develop into a crack. By reducing the proportion of the crystal grains, it is possible to reduce the probability that a crack starting point occurs. There is {111} <011>: LD as an orientation having the same sliding characteristics as {422} <011>, and the bending characteristics are still worse next to the {422} crystal plane than other low index orientations. I understood. However, the volume fraction of the {111} crystal plane hardly depended on the manufacturing process and was less than 5%, so it was omitted from the factor of improving the characteristics.

  On the other hand, in {200} crystal planes, there are 8 combinations of slip planes and slip directions that can contribute to slip in both LD: <010> and TD: <001>, and all of them are 12 types. The Schmid factor is 0.41. Furthermore, the slip line on the {200} crystal plane can have good symmetry at 45 ° and 135 ° with respect to the bending axis, so that bending deformation is possible without forming a shear band. all right.

  In order to obtain such a rolling texture, first, after using an alloy adjusted to a specific composition range, after cold rolling at a rolling rate of 80% or more in a state where precipitates are appropriately present. It is necessary to perform a solution treatment. This is because the presence of precipitates during processing can efficiently increase strain energy and stacking fault energy, and a pure copper-type recrystallized texture can be obtained by reducing solid solution elements in the matrix. . Due to the solution treatment in this state, the disappearance of the rolling texture {220} or {422} and the growth of the recrystallized texture {200} occur simultaneously. If the solution treatment is performed in an inappropriate strain energy state, {422} remains and deteriorates the bending characteristics. Therefore, before the solution treatment, {422} by X-ray diffraction before and after the solution treatment. It is necessary that the solution treatment can be performed so as to satisfy Ia {422} / Ib {422} ≦ 1, where the integrated intensities of the crystal planes are Ib {422} and Ia {422}, respectively. When cold rolling is performed after the solution treatment, a rolling texture having a {220} crystal plane as a main orientation component gradually develops. At this time, I {200} / I {422} ≧ 15 is satisfied by controlling to an intermediate crystal orientation of the above three types of textures, which is excellent in high strength and small anisotropy. Bending workability is achieved at once. This crystal orientation can be controlled by adjusting the composition and the progress of recrystallization depending on the accumulation of strain energy and stacking fault energy that satisfy Ia {422} / Ib {422} ≦ 1. Further, by reducing the volume fraction of the {422} crystal plane, an excellent bending workability with small anisotropy can be achieved without increasing the Cube orientation more than necessary. Restrictions such as strong rolling and finish rolling of 20% or less are greatly relaxed.

[Alloy composition]
The embodiment of the copper alloy sheet according to the present invention is made of a Cu—Ni—Si based copper alloy containing Cu, Ni and Si, and, if necessary, Sn, Zn as a ternary basic component of Cu—Ni—Si. , Mg and other elements may be contained.

  Ni and Si have the effect of forming Ni—Si based precipitates and improving the strength, conductivity, and thermal conductivity of the copper alloy sheet. When the Ni content is less than 0.7% by mass or the Si content is less than 0.2% by mass, it is difficult to sufficiently exhibit this effect. Therefore, the Ni content is preferably 0.7% by mass or more, more preferably 1.2% by mass or more, and further preferably 1.5% by mass or more. The Si content is preferably 0.2% by mass or more, more preferably 0.3% by mass or more, and most preferably 0.35% by mass or more. On the other hand, if the Ni content or the Si content is too high, coarse precipitates are likely to be generated and cause cracking during bending, so that both the bending workability of GoodWay and BadWay are likely to deteriorate. Therefore, the Ni content is preferably 4% by mass or less, more preferably 3.5% by mass or less, and most preferably less than 2.0% by mass. The Si content is preferably 1.0% by mass or less, more preferably 0.7% by mass or less, and most preferably less than 0.5% by mass.

The Ni—Si based precipitate formed by Ni and Si is considered to be an intermetallic compound mainly composed of Ni ₂ Si. However, Ni and Si in the alloy are not necessarily all precipitated by the aging treatment, and exist to some extent in a solid solution state in the Cu matrix. Ni and Si in the solid solution state slightly improve the strength of the copper alloy sheet, but the effect is small as compared with the precipitated state, and causes a decrease in conductivity. Therefore, the content ratio of Ni and Si is preferably as close as possible to the composition ratio of the precipitate Ni ₂ Si. Therefore, the Ni / Si mass ratio is preferably adjusted to 3.5 to 6.0, and more preferably adjusted to 3.5 to 5.0.

  Sn has a solid solution strengthening action of the copper alloy sheet. In order to fully exhibit this effect, the Sn content is preferably 0.1% by mass or more, and more preferably 0.2% by mass or more. On the other hand, if the Sn content exceeds 1.2% by mass, the electrical conductivity is remarkably lowered. Therefore, the Sn content is preferably 1.2% by mass or less, and is 0.7% by mass or less. Is more preferable.

  Zn has the effect of improving the solderability and strength of the copper alloy sheet and improving the castability. Moreover, there exists an advantage that an inexpensive brass scrap can be used by adding Zn. In order to sufficiently exhibit this effect, the Zn content is preferably 0.1% by mass or more, and more preferably 0.3% by mass or more. However, if the Zn content exceeds 2.0% by mass, the conductivity and stress corrosion cracking resistance are liable to decrease. Therefore, when Zn is added, the Zn content is set to 2.0% by mass or less. Is preferable, and it is further more preferable to set it as 1.0 mass% or less.

  Mg has the function of preventing the coarsening of Ni—Si-based precipitates and the function of improving stress relaxation resistance. In order to sufficiently exhibit these actions, it is preferable to set the Mg content to 0.01% by mass or more. However, when the Mg content exceeds 1.0% by mass, the castability and hot workability are remarkably deteriorated. Therefore, when adding Mg, the Mg content is set to 1.0% by mass or less. Is preferred.

  Other elements added to the copper alloy sheet as necessary include Co, Cr, B, P, Fe, Zr, Ti, Mn, Ag, Be, Misch metal, and the like. For example, Co, Cr, B, P, Fe, Zr, Ti, Mn, and Be have the effect of further increasing the alloy strength and reducing the stress relaxation. Co, Cr, Zr, Ti, and Mn are easy to form a high melting point compound with S, Pb, etc. present as inevitable impurities, and B, P, Zr, and Ti have an effect of refining the cast structure. Has the effect of improving hot workability. Moreover, Ag has the effect of solid solution strengthening without reducing the electrical conductivity so much. Furthermore, misch metal is a mixture of rare earth elements including Ce, La, Dy, Nd, Y, and the like, and has an effect of refining crystal grains and an effect of dispersing precipitates.

  In addition, when the copper alloy sheet material contains one or more selected from the group consisting of Co, Cr, B, P, Fe, Zr, Ti, Mn, Ag, Be, and Misch metal, the effect of adding each element In order to sufficiently obtain the above, the total amount of these is preferably 0.01% by mass or more. However, if the total amount exceeds 3% by mass, the hot workability or the cold workability is adversely affected, which is disadvantageous in terms of cost. Therefore, the total amount of these elements is preferably 3% by mass or less, and more preferably 2% by mass or less.

[Crystal orientation]
The Cu—Ni—Si based copper alloy has a strong texture with {200} crystal planes as the main orientation component as obtained by solution treatment, and the bending workability improves as the proportion of {422} crystal planes decreases. . However, finish cold rolling is indispensable for achieving high strength. When the rolling rate in the finish cold rolling is increased, a rolling texture having a {220} crystal plane as a main orientation component develops, and the improvement of bending workability by the {200} crystal plane is impaired. Furthermore, since the {422} crystal plane contributes to a decrease in bending workability even in a small amount, the property is not impaired by the development of the {220} crystal plane. Therefore, it is necessary to maintain the strength and bending workability of the copper alloy sheet at a high level by keeping the volume fraction of the {422} crystal plane low after the solution treatment.

  As a result of various studies, the present inventors have determined that the intermediate structure state is I {hkl}, where the integrated intensity of the {hkl} diffraction peak when X-ray diffraction is performed on the plate surface of the copper alloy sheet is I {hkl}. And having a crystal orientation satisfying I {200} / I {422} ≧ 15.

  When I {200} / I {422} is too small, the properties of the recrystallized texture having the {422} crystal plane as the main orientation component are relatively dominant, and the bending workability becomes extremely poor. On the other hand, when I {200} / I {422} is large, the bending workability is significantly improved at the same time in both the LD and TD directions. Further, when the alloy strength is increased by addition of Co or the like and the tensile strength becomes 800 MPa or more, it is necessary to further improve the bending workability, so that I {200} / I {422} ≧ 50 is satisfied. Is preferred.

  Further, when the integrated intensity of the {422} crystal plane by X-ray diffraction before and after the final solution treatment is Ib {422} and Ia {422}, it is preferable that Ia {422} / Ib {422} ≦ 1 is satisfied. . This equation means that the diffraction intensity of the {422} crystal plane is lowered by the solution treatment, and is a phenomenon that occurs only when the strain energy before the solution treatment and the solution treatment conditions are appropriate.

[Characteristic]
In order to reduce the size and thickness of electrical and electronic parts such as connectors, it is preferable that the tensile strength of the copper alloy plate material, which is a material, be 650 MPa or more, and more preferably 700 MPa or more. Moreover, in order to increase the strength by using age hardening, the copper alloy sheet has a metal structure that has been subjected to an aging treatment. As for the bending workability, the ratio R / t between the minimum bending radius R and the sheet thickness t in the 90 ° W bending test is preferably 1.0 or less, and is 0.5 or less in both GoodWay and BadWay. Further preferred.

[Production method]
The copper alloy sheet as described above can be produced by the embodiment of the method for producing a copper alloy sheet according to the present invention. An embodiment of a method for producing a copper alloy sheet according to the present invention includes a melting / casting step of melting and casting a copper alloy raw material having the above-described composition, and a temperature of 950 ° C. to 600 ° C. after the melting / casting step. A hot rolling process in which hot rolling is performed while lowering the temperature, a first cold rolling process in which cold rolling is performed at a rolling rate of 80% or more after the hot rolling process, and the first cold rolling process. After the step, a heat treatment step for performing a heat treatment for precipitation at a heating temperature of 500 to 600 ° C., a second cold rolling step for performing cold rolling at a rolling rate of 80% or more after the heat treatment step, After the second cold rolling step, a solution treatment step in which solution treatment is performed at a heating temperature of 700 to 980 ° C., and after this solution treatment step, intermediate cold rolling is performed at a rolling rate of 0 to 50%. Cold rolling process ("Rolling rate 0%" performs intermediate cold rolling ), An aging treatment step in which aging treatment is performed at 400 to 600 ° C. after the intermediate cold rolling step, and cold rolling at a rolling rate of 50% or less after the aging treatment step. A final cold rolling step, and in the solution treatment step, the integrated intensity of {422} crystal planes by X-ray diffraction before and after the final solution treatment is denoted by Ib {422} and Ia {422}, respectively. {422} / Ib {422} ≦ 1 is satisfied. In addition, it is preferable to heat-process (low-temperature annealing) at 150-550 degreeC after a finish cold rolling process. Further, after hot rolling, chamfering may be performed as necessary, and after heat treatment, pickling, polishing, and degreasing may be performed as necessary. Hereinafter, these steps will be described in detail.

(Melting and casting process)
A slab is produced by continuous casting or semi-continuous casting after the raw material of the copper alloy is melted by the same method as a general copper alloy melting method.

(Hot rolling process)
The slab is hot-rolled in several passes while the temperature is lowered from 950 ° C to 600 ° C. The total rolling ratio may be approximately 80 to 95%. After the hot rolling is completed, it is preferable to quench by water cooling or the like. In addition, after hot working, chamfering or pickling may be performed as necessary.

(First cold rolling process)
In this cold rolling step, the rolling rate needs to be 80% or more, and more preferably 85% or more. By subjecting the material processed at such a rolling rate to a heat treatment in the next step, the amount of precipitates can be increased.

(Heat treatment process)
Next, heat treatment for the purpose of precipitation is performed. If the precipitation is insufficient, the introduction of strain energy and stacking fault energy will be insufficient in the second cold rolling step of the next step. Specifically, it is preferably performed at a temperature of 500 to 600 ° C. The heat treatment time is about 1 to 10 hours, and good results are obtained. This heat treatment softens the Vickers hardness to about 60%, so that the rolling load in the next process is also reduced.

(Second cold rolling process)
Subsequently, the second cold rolling is performed. In this cold rolling, the rolling rate needs to be 80% or more, and more preferably 85% or more. In this cold rolling process, strain energy and stacking fault energy can be efficiently introduced due to the presence of precipitates from the previous process. When these energies are insufficient, a texture having a {422} crystal plane as a main orientation component tends to remain during solution treatment, and a recrystallized texture having a {200} crystal plane as a main orientation component is not formed. It will be enough. That is, the recrystallization texture depends on the dispersion state and amount of precipitates before recrystallization and the rolling rate in cold rolling. Note that the upper limit of the rolling rate in this cold rolling is inevitably restricted by mill power and the like, and thus it is not necessary to specify in particular. However, since it has been softened by the previous process, it is possible to perform further strong rolling. is there.

(Solution treatment process)
The solution treatment is a heat treatment that serves the two purposes of re-solution of solute elements in the matrix and recrystallization. By applying the solution treatment so that Ia {422} / Ib {422} ≦ 1 is satisfied for the material in which appropriate strain energy is introduced by performing the above heat treatment and cold rolling, the solution treatment is performed. Later, the proportion of crystals having the {422} crystal plane as the main orientation component decreases, and a recrystallized texture having the {200} crystal plane as the preferred orientation is obtained.

This solution treatment is preferably performed by adjusting the temperature and time so that the recrystallized grain size is 5 to 60 μm, and more preferably adjusted to 5 to 30 μm. If the recrystallized grain size becomes too fine, the recrystallized texture becomes weak, so that the rolled texture tends to become dominant during finish rolling, and it becomes difficult to improve the bending workability. However, it is important not to increase the solution treatment temperature excessively. Specifically, it is preferable to perform heat treatment at 700 to 980 ° C., preferably 700 to 900 ° C. for 10 seconds to 10 minutes. If the solution treatment temperature is too high, crystals having a {422} crystal plane as the main orientation component tend to remain, and the crystal grain size tends to become coarse, which tends to cause a decrease in bending workability. On the other hand, if the solution treatment temperature is too low, the recrystallization is incomplete and the solute elements are not sufficiently dissolved, and it becomes difficult to finally obtain a high-strength copper alloy sheet with excellent bending workability. . As described above, since the upper limits of the contents of Ni and Si are determined, the Ni ₂ Si phase can be sufficiently eliminated at a lower solution treatment temperature of 780 ° C. or lower. However, when Co or the like is added for the purpose of increasing the strength, the growth of recrystallized grains is suppressed, so that a temperature of 800 to 900 ° C. is required.

(Intermediate cold rolling process)
Subsequently, cold rolling is performed at a rolling rate of 0 to 50%. Cold rolling at this stage has an effect of promoting precipitation during the aging treatment of the next process, and can shorten the aging time for extracting necessary characteristics such as conductivity and hardness. This cold rolling develops a texture with {220} crystal planes as the main orientation component, but with a rolling rate of 50% or less, crystal grains whose {200} crystal planes are parallel to the plate surface are still sufficient. Remains. In particular, the rolling rate in this cold rolling contributes to the final increase in strength and improvement in bending workability by appropriately combining with the rolling rate at the finish cold pressure performed after the aging treatment. Cold rolling at this stage needs to be performed at a rolling rate of 50% or less, and is more preferably 0 to 35%. If the rolling rate is too high, precipitation occurs non-uniformly in the next aging treatment step and is likely to be over-aged, and ideal crystal orientation satisfying I {200} / I {422} ≧ 15 It becomes difficult to obtain.

  In addition, when this rolling rate is zero, it means that the intermediate aging treatment is not performed after the solution treatment and the aging treatment is directly performed. In order to improve productivity, the cold rolling process at this stage may be omitted.

(Aging process)
Subsequently, an aging process is performed. In this aging treatment, the temperature is not excessively raised under conditions effective for improving the conductivity and strength of the Cu—Ni—Si copper alloy sheet. If the aging treatment temperature becomes too high, the crystal orientation with the {200} crystal plane developed by the solution treatment as the preferred orientation is weakened and the characteristics of the {422} crystal plane become strong, resulting in sufficient bending. The effect of improving the sex may not be obtained. Specifically, it is preferably performed at a temperature of 400 to 500 ° C. The aging treatment time is about 1 to 10 hours, and good results are obtained.

(Finish cold rolling process)
In this finish cold rolling, the strength level is improved and a rolling texture having a {220} crystal plane as a main orientation component is developed. If the rolling rate of finish cold rolling is too low, the effect of increasing the strength cannot be obtained sufficiently. On the other hand, if the rolling ratio of finish cold rolling is too high, the rolling texture having the {220} crystal plane as the main orientation component becomes relatively dominant, and both strength and bending workability are good. Crystal orientation cannot be realized.

  The rolling rate of this finish cold rolling needs to be 10% or more. However, as for the upper limit of the rolling rate of finish cold rolling, the contribution of intermediate cold rolling performed before aging treatment must be taken into consideration. As a result of detailed studies by the present inventors, the upper limit is set so that the reduction rate of the sheet thickness does not exceed 50% from the solution treatment to the final step in total with the rolling ratio of the above-described intermediate cold rolling. I found it necessary. That is, if the rolling rate (%) of intermediate cold rolling is ε1 and the rolling rate (%) of finish cold rolling is ε2, 10 ≦ ε2 ≦ (50−ε1) / (100−ε1) × 100 is satisfied. To finish cold rolling.

  The final plate thickness is preferably about 0.05 to 1.0 mm, more preferably 0.08 to 0.5 mm.

(Heat treatment (low temperature annealing) process)
After the finish cold rolling step, low-temperature annealing may be performed for the purpose of reducing the residual stress of the strip material and improving the spring limit value and the stress relaxation resistance. The heating temperature is preferably set to 150 to 550 ° C. As a result, the residual stress inside the plate material is reduced, and the bending workability can be improved with almost no decrease in strength. In addition, there is an effect of improving conductivity. If this heating temperature is too high, it softens in a short time, and variations in characteristics are likely to occur in both batch and continuous systems. On the other hand, if the heating temperature is too low, the above-described effect of improving the characteristics cannot be obtained sufficiently. The heating time is preferably 5 seconds or longer, and usually good results are obtained within 1 hour.

  Hereinafter, examples of the copper alloy sheet material and the manufacturing method thereof according to the present invention will be described in detail.

[Examples 1 to 14]
1. A copper alloy (Example 1) containing 1.65% by mass of Ni and 0.40% by mass of Si with the balance being Cu, 1.64% by mass of Ni, 0.39% by mass of Si and 0.54 A copper alloy (Example 2) containing Sn of mass% and Zn of 0.44 mass%, the balance being Cu, 1.59 mass% Ni, 0.37 mass% Si and 0.48 mass% A copper alloy (Example 3) containing Sn, 0.18% by mass of Zn and 0.25% by mass of Fe, the balance being Cu, 1.52% by mass of Ni, 0.61% by mass of Si and 1 A copper alloy containing 1% by mass of Co and the balance being Cu (Example 4), a copper alloy containing 0.77% by mass of Ni and 0.20% by mass of Si and the balance being Cu (Example) 5) A copper alloy containing 3.48 mass% Ni and 0.70 mass% Si with the balance being Cu (Example 6), 2.50 A copper alloy (Example 7) containing a quantity of Ni, 0.49 mass% Si and 0.19 mass% Mg, the balance being Cu, 2.64 mass% Ni and 0.63 mass% A copper alloy containing Si, 0.13% by mass of Cr and 0.10% by mass of P, with the balance being Cu (Example 8), 2.44% by mass of Ni, 0.46% by mass of Si, and 0 Copper alloy (Example 9) containing 11 mass% Sn, 0.12 mass% Ti and 0.007 mass% B with the balance being Cu, 1.31 mass% Ni and 0.36 mass %, Si, 0.12% by mass of Zr and 0.07% by mass of Mn, the balance being Cu alloy (Example 10), 1.64% by mass of Ni and 0.39% by mass of Si And a copper alloy containing 0.54% by mass of Sn and 0.44% by mass of Zn with the balance being Cu (Example 11), 1.65% by mass A copper alloy (Example 12) comprising Ni, 0.40% by mass of Si, 0.57% by mass of Sn, and 0.52% by mass of Zn, with the balance being Cu, 3.98% by mass of Ni, A copper alloy containing 0.98 mass% Si, 0.10 mass% Ag and 0.11 mass% Be with the balance being Cu (Example 13), 3.96 mass% Ni and 0.92 A copper alloy (Example 14) containing Si in mass% and 0.21 mass% in misch metal with the balance being Cu was melted and cast using a vertical continuous casting machine to obtain a slab. .

  Each slab is heated to 950 ° C, hot rolled while lowering the temperature from 950 ° C to 600 ° C to form a plate with a thickness of 10 mm, then quenched by water cooling, and then the surface oxide layer is mechanically polished (Removal).

  Subsequently, after performing the first cold rolling at a rolling rate of 86% (Examples 1 and 5 to 14), 80% (Examples 2 and 3), and 82% (Example 4), respectively, at 520 ° C. Heat treatment was performed for 6 hours (Examples 1, 2, 5 to 14), 540 ° C. for 6 hours (Example 3), and 550 ° C. for 8 hours (Example 4). Thereafter, the rolling rate was 86% (Example 1). 5-14), 90% (Examples 2 and 3), and 89% (Example 4), the second cold rolling was performed.

Next, on the surface of the rolled plate (JIS
(Solution method by the H0501 cutting method) Hold for 10 seconds to 10 minutes at a temperature adjusted in the range of 700 to 900 ° C. according to the composition of the alloy so that the average crystal grain size is larger than 5 μm and 30 μm or less. Processed. The holding temperature and holding time in this solution treatment are determined by preliminary experiments in accordance with the compositions of the alloys of the respective examples. In Example 1, 750 ° C. for 10 minutes and in Example 2 725 ° C. 10 minutes at Example 3, 775 ° C. for 10 minutes in Example 3, 900 ° C. for 10 minutes in Example 4, 7 minutes at 700 ° C. in Example 5, 10 minutes at 850 ° C. in Examples 6 and 13-14 7 to 9 was 800 ° C. for 10 minutes, Example 10 was 700 ° C. for 10 minutes, and Examples 11 to 12 were 725 ° C. for 10 minutes. In addition, before and after this solution treatment, Ia {422} / Ib {422} is 0.89 (Examples 1 and 9), 0.92 (Examples 2 and 6), and 0.95 (Example 3), respectively. 0.91 (Examples 4, 8, and 14), 0.98 (Example 5), 0.90 (Example 7), 0.96 (Example 10), and 0.88 (Examples 11 and 12) ), 0.93 (Example 13), and in all the examples, Ia {422} / Ib {422} ≦ 1 was satisfied.

  Next, in Example 12, intermediate cold rolling was performed at a rolling rate of 12%. In other examples, the intermediate cold rolling was not performed.

  Next, an aging treatment was performed at 450 ° C. The aging treatment time was adjusted to a time when the hardness peaked at 450 ° C. according to the alloy composition. In addition, about this aging treatment time, the optimal aging treatment time was calculated | required by preliminary experiment according to the composition of the alloy of each Example, and in Examples 1-3 and 10-12, 5 hours, Examples 4, 6- 9 and 13 to 14 were 7 hours, and Example 5 was 4 hours.

  Next, finish cold rolling was performed at a rolling rate of 29% (Examples 1 to 10, 13 to 14), a rolling rate of 40% (Example 11), and a rolling rate of 17% (Example 12). ~ 12 copper alloy sheets were obtained. In addition, it chamfered on the way as needed, and the board thickness of the copper alloy board | plate material was arrange | equalized with 0.15 mm (Examples 1-10, 12-14) or 0.125 mm (Example 11).

  Next, samples were collected from the copper alloy sheet materials obtained in these examples, and the X-ray diffraction intensity, conductivity, tensile strength, and bending workability were examined as follows.

  The X-ray diffraction intensity (X-ray diffraction integrated intensity) was measured using an X-ray diffractometer (XRD) under the conditions of Mo-Kα1 and Kα2 rays, tube voltage 40 kV, tube current 30 mA (rolling). Plane), the integrated intensity I {422} of the diffraction peak of the {422} plane and the integrated intensity I {200} of the diffraction peak of the {200} plane were measured. When obvious oxidation was observed on the rolled surface of the sample, a sample polished and finished with pickling or # 1500 water-resistant paper was used. As a result, the X-ray diffraction intensity ratios I {200} / I {422} are 37 (Example 1), 20 (Example 2), 16 (Example 3), 52 (Example 4), and 16 (Example 4), respectively. Example 5), 50 (Example 6), 25 (Example 7), 27 (Example 8), 24 (Example 9), 18 (Example 10), 19 (Example 11), 38 (Example) Examples 12), 56 (Example 13), and 55 (Example 14), and all had crystal orientation satisfying I {200} / I {422} ≧ 15.

  The conductivity of the copper alloy sheet was measured according to the conductivity measurement method of JIS H0505. As a result, the conductivity was 43.1% IACS (Example 1), 40.0% IACS (Example 2), 39.4% IACS (Example 3), and 54.7% IACS (Example 4), respectively. ) 52.2% IACS (Example 5), 43.2% IACS (Example 6), 45.1% IACS (Example 7), 43.9% IACS (Example 8), 41.9% IACS (Example 9), 55.1% IACS (Example 10), 43.0% IACS (Example 11), 44.0% IACS (Example 12), 42.7% IACS (Example 13) 40.1% IACS (Example 14).

  As the tensile strength of the copper alloy sheet, three specimens for tensile test of LD (rolling direction) of the copper alloy sheet (sample No. 5 of JIS Z2241) were sampled each three, and a tensile test based on JIS Z2241 was conducted. The tensile strength was determined by the average value. As a result, the tensile strengths were 722 MPa (Example 1), 720 MPa (Example 2), 701 MPa (Example 3), 820 MPa (Example 4), 702 MPa (Example 5), and 851 MPa (Example 6), respectively. 728 MPa (Example 7), 765 MPa (Example 8), 762 MPa (Example 9), 714 MPa (Example 10), 730 MPa (Example 11), 715 MPa (Example 12), 852 MPa (Example 13), It was 856 MPa (Example 14), and all were high-strength copper alloy sheet materials having a tensile strength of 700 MPa or more.

  In order to evaluate the bending workability of the copper alloy sheet material, a bending test piece (width 10 mm) whose longitudinal direction is LD (rolling direction) and TD (direction perpendicular to the rolling direction and sheet thickness direction) from the copper alloy sheet material Three bending test pieces (width 10 mm) were sampled, and a 90 ° W bending test based on JIS H3110 was performed on each test piece. With respect to the test piece after this test, the surface and cross section of the bent portion were observed with an optical microscope at a magnification of 100 times to obtain a minimum bending radius R at which no cracks occurred, and this minimum bending radius R was obtained from a copper alloy sheet. By dividing by the thickness t, each R / t value of LD and TD was determined. Among the three test pieces of LD and TD, the result of the worst test piece was adopted to obtain the R / t value. As a result, in Examples 1 to 12, both BadWay bending using LD as a bending axis and GoodWay bending using TD as a bending axis have R / t = 0.0 and have excellent bending workability. It was. In Examples 13 to 14, Good Way bending R / t = 0.0 and Bad Way bending R / t = 0.3.

[Comparative Example 1]
A copper alloy having the same composition as in Example 1 was used, heat treatment was performed at 900 ° C. for 1 hour without performing the first cold rolling, and the rolling rate of the second cold rolling was set to 98%, and Ia {422} A copper alloy sheet was obtained in substantially the same manner as in Examples 1 to 12, except that /Ib{422}=1.6. In this comparative example, the solution treatment temperature was 750 ° C., the solution treatment time was 10 minutes, the aging time was 5 hours, the finish rolling rate was 29%, and the finished plate thickness was 0.15 mm.

  A sample was taken from the copper alloy sheet obtained in this comparative example, and the X-ray diffraction intensity, conductivity, tensile strength, and bending workability were examined by the same method as in Examples 1-12. As a result, I {200} / I {422} = 2.5, conductivity 43.4% IACS, tensile strength 733 MPa, GoodWay bending R / t = 0.3, BadWay bending R / t = 1.3.

[Comparative Example 2]
Using a copper alloy having the same composition as in Example 2, the first cold rolling reduction rate was 86%, heat treatment was performed at 900 ° C. for 0.5 hour, and the second cold rolling reduction rate was 86%. As described above, a copper alloy sheet was obtained by the same method as in Examples 1 to 12, except that Ia {422} / Ib {422} = 1.2. In this comparative example, the solution treatment temperature was 725 ° C., the solution treatment time was 10 minutes, the aging time was 5 hours, the finish rolling rate was 29%, and the finished plate thickness was 0.15 mm.

  A sample was taken from the copper alloy sheet obtained in this comparative example, and the X-ray diffraction intensity, conductivity, tensile strength, and bending workability were examined by the same method as in Examples 1-12. As a result, I {200} / I {422} = 5.4, conductivity 40.1% IACS, tensile strength 713 MPa, Good Way bending R / t = 0.3, Bad Way bending R / t = 1.3.

[Comparative Example 3]
A copper alloy having the same composition as in Example 3 was used, the first cold rolling and heat treatment were not performed, and the rolling rate of the second cold rolling was 98%, and Ia {422} / Ib {422} = 1 A copper alloy sheet was obtained in substantially the same manner as in Examples 1 to 12 except that it was set to .5. In this comparative example, the solution treatment temperature was 775 ° C., the solution treatment time was 10 minutes, the aging time was 5 hours, the finish rolling rate was 29%, and the finished plate thickness was 0.15 mm.

  A sample was taken from the copper alloy sheet obtained in this comparative example, and the X-ray diffraction intensity, conductivity, tensile strength, and bending workability were examined by the same method as in Examples 1-12. As a result, I {200} / I {422} = 6.2, conductivity 39.1% IACS, tensile strength 691 MPa, Good Way bending R / t = 0.7, Bad Way bending R / t = 1.3.

[Comparative Example 4]
A copper alloy having substantially the same composition as that of Example 4 (copper alloy containing 1.54% by mass of Ni, 0.62% by mass of Si and 1.1% by mass of Co, with the balance being Cu) is used. 1 is not subjected to cold rolling, heat treatment is performed at 550 ° C. for 1 hour, the rolling rate of the second cold rolling is 96%, and Ia {422} / Ib {422} = 1.4. A copper alloy sheet was obtained in substantially the same manner as in Examples 1-12. In this comparative example, the solution treatment temperature was 900 ° C., the solution treatment time was 10 minutes, the aging time was 7 hours, the finish rolling rate was 65%, and the finished plate thickness was 0.15 mm.

  A sample was taken from the copper alloy sheet obtained in this comparative example, and the X-ray diffraction intensity, conductivity, tensile strength, and bending workability were examined by the same method as in Examples 1-12. As a result, I {200} / I {422} = 10, conductivity is 57.5% IACS, tensile strength is 789 MPa, GoodWay bending R / t = 2.0, BadWay bending R / t = 3. 0.

[Comparative Example 5]
A copper alloy containing 0.46% by mass of Ni, 0.13% by mass of Si and 0.16% by mass of Mg and the balance being Cu is used, and the rolling ratio of the first cold rolling is 86%. Substantially the same as in Examples 1 to 12 except that heat treatment was performed at 520 ° C. for 6 hours, the rolling ratio of the second cold rolling was 86%, and Ia {422} / Ib {422} = 1.7. By this method, a copper alloy sheet was obtained. In this comparative example, the solution treatment temperature was 600 ° C., the solution treatment time was 10 minutes, the aging time was 5 hours, the finish rolling rate was 29%, and the finished plate thickness was 0.15 mm.

  A sample was taken from the copper alloy sheet obtained in this comparative example, and the X-ray diffraction intensity, conductivity, tensile strength, and bending workability were examined by the same method as in Examples 1-12. As a result, I {200} / I {422} = 1.9, conductivity 55.7% IACS, tensile strength 577 MPa, Good Way bending R / t = 0.0, Bad Way bending R / t = 0.0.

[Comparative Example 6]
5. Using a copper alloy containing 20% by mass of Ni, 1.20% by mass of Si, 0.51% by mass of Sn and 0.46% by mass of Zn, with the balance being Cu, the first cold Except that the rolling rate of rolling was 86%, heat treatment was performed at 520 ° C. for 6 hours, the rolling rate of the second cold rolling was 86%, and Ia {422} / Ib {422} = 1.1. A copper alloy sheet was obtained in substantially the same manner as in Examples 1-12. In this comparative example, the solution treatment temperature was 925 ° C., the solution treatment time was 10 minutes, the aging time was 7 hours, the finish rolling rate was 29%, and the finished plate thickness was 0.15 mm.

  A sample was taken from the copper alloy sheet obtained in this comparative example, and the X-ray diffraction intensity, conductivity, tensile strength, and bending workability were examined by the same method as in Examples 1-12. As a result, I {200} / I {422} = 13, conductivity 36.7% IACS, tensile strength 871 MPa, Good Way bending R / t = 1.0, Bad Way bending R / t = 3. 3.

  The compositions and production conditions of these Examples and Comparative Examples are shown in Table 1 and Table 2, respectively, and the results on the structure and properties are shown in Table 3.

  From the above results, in Comparative Examples 1 to 4, although it is a copper alloy sheet having substantially the same composition as Examples 1 to 4, cold rolling and heat treatment before solution treatment are not appropriate, strain energy and Since the stacking fault energy could not be sufficiently accumulated, many crystal grains having {422} crystal planes as main orientation components remained, the relative amount of {200} crystal planes became insufficient, and the tensile strength and conductivity were low. Although it was almost the same, bending workability was lowered. Moreover, in Comparative Example 5, since the Ni content and the Si content were too low, the generation of precipitates was small and the strength level was low. Furthermore, in Comparative Example 6, since the Ni content and the Si content were too high, the orientation control was insufficient and the tensile strength was high, but the bending workability was very poor.

Claims (16)

{Hkl when the composition contains 0.7 to 4% by mass of Ni and 0.2 to 1.0% by mass of Si, and the balance is Cu and inevitable impurities, and X-ray diffraction is performed on the plate surface. } A copper alloy sheet having a crystal orientation satisfying I {200} / I {422} ≧ 15 when the integrated intensity of diffraction peaks is I {hkl}. 2. The copper alloy sheet according to claim 1, wherein the copper alloy sheet has a composition further containing 0.1 to 1.2 mass% of Sn. The said copper alloy board | plate material has a composition which further contains 2.0 mass% or less Zn, The copper alloy board | plate material of Claim 1 or 2 characterized by the above-mentioned. The copper alloy sheet according to any one of claims 1 to 3, wherein the copper alloy sheet has a composition further containing 1.0% by mass or less of Mg. The copper alloy sheet further includes one or more elements selected from the group consisting of Co, Cr, B, P, Fe, Zr, Ti, Mn, Ag, Be, and Misch metal in a range of 3% by mass or less in total. It has a composition, The copper alloy plate material in any one of Claims 1 thru | or 4 characterized by the above-mentioned. The copper alloy sheet according to claim 1, wherein the copper alloy sheet has a tensile strength of 700 MPa or more. The copper alloy sheet according to claim 6, wherein the copper alloy sheet has a tensile strength of 800 MPa or more and a crystal orientation satisfying I {200} / I {422} ≧ 50. A melting and casting step of melting and casting a raw material of a copper alloy having a composition containing 0.7 to 4% by mass of Ni and 0.2 to 1.0% by mass of Si, the balance being Cu and inevitable impurities; A hot rolling step of performing hot rolling while lowering the temperature from 950 ° C. to 600 ° C. after the melting and casting step, and a first of performing cold rolling at a rolling rate of 80% or more after the hot rolling step A cold rolling step, a heat treatment step in which heat treatment is performed at a heating temperature of 500 to 600 ° C. after the first cold rolling step, and a second cold step in which cold rolling is performed at a rolling rate of 80% or more after the heat treatment step. An intermediate cold rolling step, a solution treatment step for performing solution treatment at 700 to 980 ° C. after the second cold rolling step, and intermediate cold rolling at a rolling rate of 0 to 50% after the solution treatment step. The intermediate cold rolling process to be performed and after this intermediate cold rolling process An aging treatment step of carrying out an aging treatment at 400 to 600 ° C., and in the solution treatment step, the integrated intensity of {422} crystal planes by X-ray diffraction before and after the solution treatment is expressed as Ib {422} and A method for producing a copper alloy sheet material, wherein Ia {422} satisfies Ia {422} / Ib {422} ≦ 1. The method for producing a copper alloy sheet according to claim 8, further comprising a finish rolling step of performing cold rolling at a rolling rate of 50% or less after the aging treatment step. The method for producing a copper alloy sheet according to claim 8 or 9, further comprising a low-temperature annealing step in which heat treatment is performed at 150 to 550 ° C after the finish cold rolling step. The said copper alloy board | plate material has a composition which further contains 0.1-1.2 mass% Sn, The manufacturing method of the copper alloy board | plate material in any one of Claims 8 thru | or 10 characterized by the above-mentioned. The method for producing a copper alloy sheet according to any one of claims 8 to 11, wherein the copper alloy sheet has a composition further containing 2.0% by mass or less of Zn. The method for producing a copper alloy sheet according to any one of claims 8 to 12, wherein the copper alloy sheet has a composition further containing 1.0% by mass or less of Mg. The copper alloy sheet further includes one or more elements selected from the group consisting of Co, Cr, B, P, Fe, Zr, Ti, Mn, Ag, Be, and Misch metal in a range of 3% by mass or less in total. It has a composition, The manufacturing method of the copper alloy board | plate material in any one of Claims 8 thru | or 13 characterized by the above-mentioned. An electrical / electronic component using the copper alloy sheet according to claim 1 as a material. The electrical / electronic component according to claim 15, wherein the electrical / electronic component is a connector, a lead frame, a relay, or a switch.