JP2006009108A

JP2006009108A - Cu-Ni-Si BASED COPPER ALLOY STRIP HAVING EXCELLENT BENDING WORKABILITY

Info

Publication number: JP2006009108A
Application number: JP2004189347A
Authority: JP
Inventors: Hiroyasu Ishikawa; 泰靖石川; Takatsugu Hatano; 隆紹波多野
Original assignee: Nikko Metal Manufacturing Co Ltd
Current assignee: Nippon Mining Holdings Inc
Priority date: 2004-06-28
Filing date: 2004-06-28
Publication date: 2006-01-12
Anticipated expiration: 2024-06-28
Also published as: JP4166196B2

Abstract

<P>PROBLEM TO BE SOLVED: To provide a Cu-Ni-Si based copper alloy strip for an electronic material in which high strength and excellent bending workability are consistent. <P>SOLUTION: In the copper alloy comprising 1.0 to 4.5% Ni and 0.25 to 1.5% Si, and, if required, comprising small amounts of Mg, Zn, Sn, Fe, Ti, Zr, Cr, Al, P, Mn, Ag or Be, the crystal orientation is controlled so as to be (I<SB>(111)</SB>+I<SB>(311)</SB>)/I<SB>(220)</SB>≤2.0 (I<SB>(hkl)</SB>is the X-ray diffraction intensity at the sheet face in the (hkl) face), thus the reverse anisotropy of bending is improved. Further, by controlling the I<SB>(220)</SB>and crystal grain form to proper ranges, the balance of satisfactory strength and bending workability is obtained. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

本発明は、高強度かつ曲げ加工性に優れた電子材料などの電子部品の製造に使用するＣｕ−Ｎｉ−Ｓｉ系銅合金条に関するものである。 The present invention relates to a Cu—Ni—Si based copper alloy strip used for manufacturing electronic parts such as electronic materials having high strength and excellent bending workability.

近年、リードフレーム、電子機器の各種端子、コネクタなどにおいて、リード数などの増加、狭ピッチ化が急速に進み、電子部品の高密度実装性、高信頼性が要求されている。高密度実装性および高信頼性の観点から、電子部品に用いられる材料においても、高強度および高導電性は勿論のこと、１８０°密着曲げやノッチング後の９０°曲げなど、様々な厳しい曲げ加工に耐えられるような優れた曲げ加工性など、要求される特性は益々厳しくなってきている。その中でも、Ｃｕ−Ｎｉ−Ｓｉ系銅合金条は、高強度、高導電率、高耐熱性および高耐応力緩和特性を兼ね備えた銅合金としてリードフレーム、電子機器の各種端子、コネクタなどの材料として実用化されている。 In recent years, lead frames, various terminals of electronic devices, connectors, and the like have rapidly increased in the number of leads and narrowed pitch, and high-density mounting and high reliability of electronic components are required. From the viewpoint of high-density mounting and high reliability, not only high strength and high conductivity, but also various severe bending processes such as 180 ° close contact bending and 90 ° bending after notching are used in materials used for electronic components. The required properties, such as excellent bendability that can withstand temperatures, are becoming increasingly severe. Among them, Cu-Ni-Si-based copper alloy strips are copper alloys that combine high strength, high electrical conductivity, high heat resistance, and high stress relaxation properties, as materials for lead frames, various terminals of electronic devices, connectors, etc. It has been put into practical use.

しかしながら、高強度と優れた曲げ加工性の兼備は難しいのが現状である。特にＣｕ−Ｎｉ−Ｓｉ系銅合金条では、曲げ軸を圧延方向と直角にとった場合（以下、ＧｏｏｄＷａｙとする）の曲げ加工性が、曲げ軸を圧延方向と平行にとった場合の曲げ加工性（以下、ＢａｄＷａｙとする）より劣るという問題があった。この場合、曲げ異方性は、他の銅合金条がＧｏｏｄＷａｙの曲げ加工性の方が良好であるということとは逆であることから、Ｃｕ−Ｎｉ−Ｓｉ系銅合金条においてはＧｏｏｄＷａｙの曲げ加工性改善が強く求められてきた。 However, at present, it is difficult to combine high strength and excellent bending workability. In particular, in the Cu-Ni-Si-based copper alloy strip, the bending workability when the bending axis is perpendicular to the rolling direction (hereinafter referred to as Good Way) is the bending when the bending axis is parallel to the rolling direction. There was a problem that it was inferior to workability (hereinafter referred to as Bad Way). In this case, the bending anisotropy is contrary to the fact that the other copper alloy strips are better in the bending workability of Good Way. Therefore, in the Cu—Ni—Si based copper alloy strip, Good Way There has been a strong demand for improved bending workability.

Ｃｕ−Ｎｉ−Ｓｉ系銅合金条の曲げ加工性を改善する方策として、析出物を制御すること（例えば、特許文献１参照。）、結晶粒の形態を制御すること（例えば、特許文献２参照。）などが提案されている。一方、結晶方位を制御し曲げ加工性を改善することも、特許文献３で提案されている。この発明では、再結晶粒径を大きくすると（２００）および（３１１）面の集積度が増し、圧延すると（２２０）面の集積度が増すことに基づき、これら三面のＸ線回折強度（Ｉ）の関係を、次式で規定している。
（Ｉ_{（２００）}＋Ｉ_{（３１１）}）／Ｉ_{（２２０）}≧０.５ As measures for improving the bending workability of the Cu—Ni—Si-based copper alloy strip, control of precipitates (for example, see Patent Document 1), control of crystal grain shape (for example, see Patent Document 2) Etc.) have been proposed. On the other hand, it has also been proposed in Patent Document 3 to improve the bending workability by controlling the crystal orientation. In this invention, when the recrystallized grain size is increased, the degree of integration of the (200) and (311) planes increases, and when rolling, the degree of integration of the (220) plane increases. Is defined by the following equation.
(I ₍₂₀₀₎ + I ₍₃₁₁₎ ) / I ₍₂₂₀₎ ≧ 0.5

この関係式は、結晶粒径を大きくし、最終圧延加工度を低くすると曲げ加工性が向上することを述べている。しかしながら、結晶粒の粗大化および最終圧延加工度の低減は、強度低下を伴なう。また、結晶粒の粗大化については、曲げ割れは改善されたとしても、曲げ表面の肌荒れ（シワ）が大きくなり部品の外観が劣化するという問題がある。さらに、結晶粒の粗大化および最終圧延加工度の低減により、ＧｏｏｄＷａｙおよびＢａｄＷａｙの曲げ加工性が同時に向上するものの、ＧｏｏｄＷａｙの曲げがＢａｄＷａｙの曲げに劣るという、Ｃｕ−Ｎｉ−Ｓｉ系銅合金条で課題とされてきた曲げの逆異方性は改善されない。なお、本発明においては、ＧｏｏｄＷａｙの曲げがＢａｄＷａｙの曲げに劣るという現象を曲げの逆異方性と表現する。 This relational expression states that bending workability improves when the crystal grain size is increased and the final rolling degree is lowered. However, the coarsening of crystal grains and the reduction of the final rolling degree are accompanied by a decrease in strength. Further, regarding the coarsening of crystal grains, even if the bending crack is improved, there is a problem that the rough surface (wrinkle) of the bending surface becomes large and the appearance of the part deteriorates. Further, although the workability of Good Way and Bad Way is improved at the same time due to the coarsening of crystal grains and the reduction of the final rolling workability, the bending of Good Way is inferior to that of Bad Way. The reverse anisotropy of bending, which has been a problem with copper alloy strips, is not improved. In the present invention, the phenomenon that the bending of Good Way is inferior to the bending of Bad Way is expressed as reverse anisotropy of bending.

特開２００１−４９３６９号公報JP 2001-49369 A 特開２００２−３８２２８号公報JP 2002-38228 A 特開２０００−８０４２８号公報JP 2000-80428 A

そこで、結晶粒粗大化および最終圧延加工度の低減の手段を使用することなく、Ｃｕ−Ｎｉ−Ｓｉ系銅合金条の結晶方位を曲げ加工性に対し最適化することが望まれていた。
本発明は結晶粒粗大化および最終圧延加工度の低減の手段を使用することなく、Ｃｕ−Ｎｉ−Ｓｉ系銅合金条の結晶方位を最適化するためになされたもので、高強度および優れた曲げ加工性を両立させた電子材料用Ｃｕ−Ｎｉ−Ｓｉ系銅合金条を提供することを目的としている。曲げ加工性については、特にＧｏｏｄＷａｙの曲げ加工性を向上させ、曲げの逆異方性を改善することを課題としている。 Therefore, it has been desired to optimize the crystal orientation of the Cu—Ni—Si based copper alloy strip for bending workability without using means for coarsening the crystal grains and reducing the final rolling workability.
The present invention was made to optimize the crystal orientation of the Cu-Ni-Si-based copper alloy strip without using means for coarsening the grain and reducing the final rolling workability. An object of the present invention is to provide a Cu-Ni-Si-based copper alloy strip for electronic materials that achieves both bending workability. Regarding bending workability, the object is to improve the bending workability of Good Way, and to improve the reverse anisotropy of bending.

上記目的を達成するために本発明者らは、Ｃｕ−Ｎｉ−Ｓｉ系銅合金条の研究を重ねたところ、高強度および優れた曲げ加工性を両立させたＣｕ−Ｎｉ−Ｓｉ系銅合金条の開発に成功した。 In order to achieve the above object, the present inventors have conducted research on Cu—Ni—Si based copper alloy strips. As a result, Cu—Ni—Si based copper alloy strips having both high strength and excellent bending workability are achieved. Was successfully developed.

即ち本発明は、
（１）Ｎｉを１．０〜４．５質量％（以下％とする）、Ｓｉを０．２５〜１．５％含有し、残部がＣｕおよび不可避的不純物よりなる銅基合金の圧延面においてＸ線回折を用いて測定した３つの（ｈｋｌ）面のＸ線回折強度が
（式１）（Ｉ_{（１１１）}＋Ｉ_{（３１１）}）／Ｉ_{（２２０）}≦２．０
を満足することを特徴とする高強度および優れた曲げ加工性を両立させたＣｕ−Ｎｉ−Ｓｉ系銅合金条、
（２）圧延面においてＸ線回折を用いて測定した（２２０）面のＸ線回折強度をＩ_{（２２０）}、および純銅粉末標準試料においてＸ線回折を用いて測定した（２２０）面のＸ線回折強度をＩ_{０（２２０）}としたときのＩ_{（２２０）}/Ｉ_{０（２２０）}が
（式２）１．０≦Ｉ_{（２２０）}/Ｉ_{０（２２０）}≦３．０
を満足することを特徴とする上記（１）に記載のＣｕ−Ｎｉ−Ｓｉ系銅合金条、
（３）圧延方向と直角な断面における結晶粒の幅方向の平均長さをａ、厚み方向の平均長さをｂとしたときに
（式３）
０．５≦ｂ／ａ≦０．９
２μｍ≦ａ≦２０μｍ
であることを特徴とする上記（１）または（２）に記載のＣｕ−Ｎｉ−Ｓｉ系銅合金条、
（４）Ｍｇを０．０５〜０．３％含有することを特徴とする上記（１）〜（３）に記載のＣｕ−Ｎｉ−Ｓｉ系銅合金条、
（５）Ｚｎ、Ｓｎ、Ｆｅ、Ｔｉ、Ｚｒ、Ｃｒ、Ａｌ、Ｐ、Ｍｎ、Ａｇ、またはＢｅのうち１種類以上を総量で０．００５〜２．０％含有することを特徴とする上記（１）〜（４）に記載のＣｕ−Ｎｉ−Ｓｉ系銅合金条、
である。 That is, the present invention
(1) On the rolling surface of a copper-based alloy containing 1.0 to 4.5% by mass (hereinafter referred to as%) of Ni, 0.25 to 1.5% of Si, and the balance of Cu and inevitable impurities The X-ray diffraction intensities of the three (hkl) planes measured using X-ray diffraction are (Equation 1) (I ₍₁₁₁₎ + I ₍₃₁₁₎ ) / I ₍₂₂₀₎ ≦ 2.0
Cu-Ni-Si-based copper alloy strips having both high strength and excellent bending workability, characterized by satisfying
(2) The X-ray diffraction intensity of (220) plane measured using X-ray diffraction on the rolled surface is I ₍₂₂₀₎ , and the X-ray of (220) plane measured using X-ray diffraction on a pure copper powder standard sample When the diffraction intensity is I _{0 (220)} , I ₍₂₂₀₎ / I _{0 (220)} is (Expression 2) 1.0 ≦ I ₍₂₂₀₎ / I _{0 (220)} ≦ 3.0
The Cu—Ni—Si based copper alloy strip described in (1) above, wherein:
(3) When the average length in the width direction of the crystal grains in the cross section perpendicular to the rolling direction is a and the average length in the thickness direction is b (Equation 3)
0.5 ≦ b / a ≦ 0.9
2μm ≦ a ≦ 20μm
The Cu—Ni—Si based copper alloy strip described in (1) or (2) above,
(4) The Cu—Ni—Si based copper alloy strip described in (1) to (3) above, containing 0.05 to 0.3% of Mg,
(5) The above, characterized by containing one or more of Zn, Sn, Fe, Ti, Zr, Cr, Al, P, Mn, Ag, or Be in a total amount of 0.005 to 2.0% ( Cu-Ni-Si-based copper alloy strips according to 1) to (4),
It is.

以上説明した通り、本発明は、高強度かつ曲げ加工性に優れ、さらに、曲げ異方性が小さく、リードフレーム、端子、コネクタなどの電子材料用銅合金として好適である。 As described above, the present invention is suitable as a copper alloy for electronic materials such as lead frames, terminals, connectors, and the like because of high strength and excellent bending workability and low bending anisotropy.

次に、本発明において銅合金の組成範囲、結晶方位および結晶粒形状を上記の通りに限定した理由を具体的に説明する。
Ｎｉ及びＳｉ濃度
Ｎｉ及びＳｉは、時効処理を行うことによりＮｉとＳｉが微細なＮｉ_２Ｓｉを主とした金属間化合物の析出粒子を形成し、合金の強度を著しく増加させる。また、時効処理でのＮｉ_２Ｓｉの析出に伴い、導電性が向上する。ただし、Ｎｉ濃度が１．０％未満の場合、またはＳｉ濃度が０．２５％未満の場合は、他方の成分を添加しても所望とする強度が得られない。また、Ｎｉ濃度が４．５％を超える場合、またはＳｉ濃度が１．５％を超える場合は十分な強度が得られるものの、導電性が低くなり、更には強度の向上に寄与しない粗大なＮｉ−Ｓｉ系粒子（晶出物及び析出物）が母相中に生成し、曲げ加工性、エッチング性およびめっき性の低下を招く。よって、Ｎｉ濃度を１．０〜４．５％、Ｓｉ濃度を０．２５〜１．５％と定めた。 Next, the reason why the composition range, crystal orientation, and crystal grain shape of the copper alloy are limited as described above in the present invention will be specifically described.
Ni and Si Concentrations Ni and Si are formed by aging treatment to form precipitated particles of intermetallic compounds mainly composed of Ni ₂ Si in which Ni and Si are fine, and remarkably increase the strength of the alloy. Further, the conductivity is improved with the precipitation of Ni ₂ Si in the aging treatment. However, when the Ni concentration is less than 1.0% or the Si concentration is less than 0.25%, the desired strength cannot be obtained even if the other component is added. Further, when the Ni concentration exceeds 4.5%, or when the Si concentration exceeds 1.5%, sufficient strength can be obtained, but the conductivity becomes low, and further coarse Ni that does not contribute to the improvement of the strength. -Si-based particles (crystallized substances and precipitates) are generated in the matrix phase, and bending workability, etching properties and plating properties are reduced. Therefore, the Ni concentration is set to 1.0 to 4.5%, and the Si concentration is set to 0.25 to 1.5%.

Ｍｇ濃度
Ｍｇには応力緩和特性を大幅に改善する効果および熱間加工性を改善する効果があるが、０．０５％未満ではその効果が得られず、０．３０％を超えると鋳造性（鋳肌品質の低下）、熱間加工性およびめっき耐熱剥離性が低下するためＭｇの濃度を０．０５〜０．３％と定めた。より好ましいＭｇ濃度は、０．１〜０．２％である。 Mg concentration Mg has the effect of greatly improving the stress relaxation properties and the hot workability, but if it is less than 0.05%, the effect cannot be obtained, and if it exceeds 0.30%, castability ( (Deterioration of casting surface quality), hot workability and plating heat-resistant peelability are lowered, so the Mg concentration is determined to be 0.05 to 0.3%. A more preferable Mg concentration is 0.1 to 0.2%.

Ｚｎ、Ｓｎ、Ｆｅ、Ｔｉ、Ｚｒ、Ｃｒ、Ａｌ、Ｐ、Ｍｎ、Ａｇ、またはＢｅ
Ｚｎ、Ｓｎ、Ｆｅ、Ｔｉ、Ｚｒ、Ｃｒ、Ａｌ、Ｐ、Ｍｎ、Ａｇ、またはＢｅには、Ｃｕ−Ｎｉ−Ｓｉ系銅合金条の強度及び耐熱性を改善する作用がある。また、これらの中でＺｎには、半田接合の耐熱性を改善する効果もあり、Ｆｅには組織を微細化する効果もある。更にＴｉ、Ｚｒ、Ａｌ及びＭｎは熱間圧延性を改善する効果を有する。この理由は、これらの元素が硫黄との親和性が強いため硫黄と化合物を形成し、熱間圧延割れの原因であるインゴット粒界への硫化物の偏析を軽減するためである。Ｚｎ、Ｓｎ、Ｆｅ、Ｔｉ、Ｚｒ、Ｃｒ、Ａｌ、Ｐ、Ｍｎ、Ａｇ、またはＢｅの濃度が総量で０．００５％未満であると上記の効果は得られず、総含有量が２．０％を越えると導電性が著しく低下する。そこで、これらの含有量を総量で０．００５〜２．０％と定めた。より好ましい含有量は、総量で０．０１〜１％である。 Zn, Sn, Fe, Ti, Zr, Cr, Al, P, Mn, Ag, or Be
Zn, Sn, Fe, Ti, Zr, Cr, Al, P, Mn, Ag, or Be has an effect of improving the strength and heat resistance of the Cu—Ni—Si based copper alloy strip. Of these, Zn also has an effect of improving the heat resistance of the solder joint, and Fe has an effect of refining the structure. Furthermore, Ti, Zr, Al, and Mn have an effect of improving hot rollability. This is because these elements have a strong affinity for sulfur and form a compound with sulfur to reduce the segregation of sulfide to the ingot grain boundaries, which is the cause of hot rolling cracks. When the total concentration of Zn, Sn, Fe, Ti, Zr, Cr, Al, P, Mn, Ag, or Be is less than 0.005%, the above effect cannot be obtained, and the total content is 2.0. If it exceeds 50%, the electrical conductivity is remarkably lowered. Therefore, these contents are determined to be 0.005 to 2.0% in total. A more preferable content is 0.01 to 1% in total.

（式１）〜（式３）について
Ｃｕ−Ｎｉ−Ｓｉ系銅合金条は、熱間圧延、冷間圧延、溶体化処理、冷間圧延、時効処理、必要に応じて仕上げ圧延および歪取り焼鈍という工程で作られ、熱間圧延工程（加工度、温度、歪速度）、溶体化処理（溶体化温度、時間）および冷間圧延工程（加工度）などが、各方位の集積度に影響を及ぼす。なお、この集積度は、時効処理および歪取り焼鈍によって大きく変化することはない。また、結晶粒径は、主として溶体化処理の条件によって決定される。
本発明者らは、Ｃｕ−Ｎｉ−Ｓｉ系銅合金条を種々の条件で製造したときの各結晶面の集積度および結晶粒形態と曲げ加工性および曲げ異方性の関係を調査、解析した結果、以下の知見を得た。 About (Formula 1)-(Formula 3) Cu-Ni-Si system copper alloy strip is hot-rolled, cold-rolled, solution treatment, cold-rolled, aging-treated, and finish-rolled and strain-relieved annealing as necessary. The hot rolling process (working degree, temperature, strain rate), solution treatment (solution temperature, time) and cold rolling process (working degree) affect the degree of integration in each direction. Effect. This degree of integration does not change greatly due to aging treatment and strain relief annealing. The crystal grain size is mainly determined by the solution treatment conditions.
The present inventors investigated and analyzed the relationship between the degree of integration of each crystal plane and the crystal grain morphology, bending workability and bending anisotropy when Cu—Ni—Si based copper alloy strips were produced under various conditions. As a result, the following knowledge was obtained.

（１）（１１１）面および（３１１）面の集積度が、曲げ異方性と強い相関を持ち、（２２０）面の集積度が曲げ加工性と強い相関を持っていることが新たに分かった。具体的には、（２２０）面の回折強度と（１１１）面および（３１１）面の回折強度の割合を制御することで、曲げ異方性を制御できる。この３つの結晶面の回折強度の割合（以下、板面方位指数と略す。）を次の範囲に調節することで、曲げ異方性が小さくなり、ＧｏｏｄＷａｙおよびＢａｄＷａｙの曲げ加工性が同等になる。
（式１）（I_{（１１１）}+I_{（３１１）}）/I_{（２２０）}≦２．０
この板面方位指数は、熱間圧延温度を高くし、溶体化処理温度、時間、冷間圧延加工度を制御することで得られた。 (1) It is newly found that the integration degree of (111) plane and (311) plane has a strong correlation with bending anisotropy, and the integration degree of (220) plane has a strong correlation with bending workability. It was. Specifically, the bending anisotropy can be controlled by controlling the ratio of the diffraction intensity of the (220) plane and the diffraction intensity of the (111) plane and the (311) plane. By adjusting the ratio of the diffraction intensity of these three crystal planes (hereinafter abbreviated as plate plane orientation index) to the following range, the bending anisotropy is reduced, and the bending workability of Good Way and Bad Way is equivalent. become.
(Formula 1) (I ₍₁₁₁₎ + I ₍₃₁₁₎ ) / I ₍₂₂₀₎ ≦ 2.0
This plate surface orientation index was obtained by increasing the hot rolling temperature and controlling the solution treatment temperature, time, and cold rolling work degree.

（２）（２２０）面の集積度（以下、集積度と略す。）が低くなると強度が低下し、ＧｏｏｄＷａｙおよびＢａｄＷａｙの曲げ加工性が同時に向上する。集積度を次の範囲に調節することで、所望の強度と曲げ加工性が得られる。
（式２）１.０≦I_{（２２０）}/I_{０（２２０）}≦３．０
この集積度は、溶体化処理後以降の冷間圧延加工度を高くすると高くなる。また、溶体化温度が低くなると集積度が高くなり、溶体化時間を短くすると集積度が高くなる。 (2) When the integration degree of the (220) plane (hereinafter abbreviated as integration degree) decreases, the strength decreases, and the bending workability of Good Way and Bad Way improves at the same time. The desired strength and bending workability can be obtained by adjusting the degree of integration to the following range.
(Formula 2) 1.0 ≦ I ₍₂₂₀₎ / I _{0 (220)} ≦ 3.0
This degree of integration increases as the degree of cold rolling after the solution treatment is increased. Further, the integration degree increases as the solution temperature decreases, and the integration degree increases as the solution time decreases.

（３）結晶粒径を図１の様に圧延平行方向と直角な断面における結晶粒の幅方向の平均長さをａ、厚み方向の平均長さをｂとしたときに、下式の範囲に調整することで所望の強度と曲げ加工性が得られる。
０．５≦ｂ／ａ≦０．９
２μｍ≦ａ≦２０μｍ
ｂ／ａが０．５を下回るとＧｏｏｄＷａｙおよびＢａｄＷａｙの曲げ加工性は同時に向上するが強度が低くなり、０．９を超えると強度は高くなるがＧｏｏｄＷａｙおよびＢａｄＷａｙの曲げ加工性が同時に悪化する。一方、ａが２０μｍを超えると強度が低下し、ＧｏｏｄＷａｙおよびＢａｄＷａｙの曲げ部の肌荒れが大きくなる。また、２μｍを下回るａの値を得るには、不充分な溶体化処理を行わざるを得ないため、時効処理の際の析出量が減り、強度が低下する。なお、所望とする結晶粒形態は溶体化処理温度と時間を制御することで得られた。 (3) The crystal grain size is within the range of the following formula, where a is the average length in the width direction of the crystal grains in the cross section perpendicular to the rolling parallel direction as shown in FIG. By adjusting, desired strength and bending workability can be obtained.
0.5 ≦ b / a ≦ 0.9
2μm ≦ a ≦ 20μm
When b / a is less than 0.5, the bending workability of Good Way and Bad Way is improved at the same time, but the strength is low, and when it exceeds 0.9, the strength is high but the bending workability of Good Way and Bad Way is high. It gets worse at the same time. On the other hand, when a exceeds 20 μm, the strength decreases, and the roughened skin of the bent portions of Good Way and Bad Way increases. In addition, in order to obtain a value of less than 2 μm, an insufficient solution treatment is required, so that the amount of precipitation during the aging treatment is reduced and the strength is lowered. In addition, the desired crystal grain form was obtained by controlling the solution treatment temperature and time.

（１）実施例１
次に、本発明の実施例について比較例とともに説明する。
電気銅を原料とし、大気溶解炉を用いてＣｕ−２．３±０．１％Ｎｉ−０．５０±０．０１％Ｓｉ−０．１±０．０２％Ｍｇの銅合金を溶製し、厚さ２０ｍｍ×幅６０ｍｍのインゴットに鋳造した。このインゴットを次の工程で加工し、厚さ０．３ｍｍの試料を得た。
（ａ）熱間圧延：表１に示す条件で板厚３ｍｍまで熱間圧延を行った。種々の温度で３時間の均質化焼鈍を施した後、この温度で熱間圧延を開始した。そして、熱間圧延中に温度低下を防止するために、厚みが１５、１０および５ｍｍになった時点で、圧延途中の材料を熱間圧延開始温度にて３０分間加熱した（以下、再加熱）。ただし、比較例Ｎｏ．７では再加熱を実施しなかったため、熱間圧延終了温度が５５０℃まで低下した。
（ｂ）面削：グラインダー研磨により表面スケールを除去した。
（ｃ）冷間圧延：厚さ０．６２５ｍｍまで加工した。
（ｄ）溶体化処理：８００℃で３分間加熱し、水冷した。ここで、加熱時間は、材料温度が８００℃に達した後、水冷を開始するまでの時間である。
（ｅ）冷間圧延：厚さ０．５ｍｍまで加工した。
（ｆ）時効処理：０．２％耐力が最大となる温度で３時間の時効処理を行った。この温度は４００〜６００℃の範囲であった。 (1) Example 1
Next, examples of the present invention will be described together with comparative examples.
Cu-2.3 ± 0.1% Ni-0.50 ± 0.01% Si-0.1 ± 0.02% Mg copper alloy is melted using electrolytic copper as a raw material using an atmospheric melting furnace. This was cast into an ingot having a thickness of 20 mm and a width of 60 mm. The ingot was processed in the next step to obtain a sample having a thickness of 0.3 mm.
(A) Hot rolling: Hot rolling was performed up to a plate thickness of 3 mm under the conditions shown in Table 1. After performing homogenization annealing for 3 hours at various temperatures, hot rolling was started at this temperature. And in order to prevent a temperature drop during hot rolling, when the thickness became 15, 10 and 5 mm, the material in the middle of rolling was heated for 30 minutes at the hot rolling start temperature (hereinafter, reheating). . However, Comparative Example No. In No. 7, since reheating was not performed, the hot rolling end temperature decreased to 550 ° C.
(B) Chamfering: The surface scale was removed by grinder polishing.
(C) Cold rolling: processed to a thickness of 0.625 mm.
(D) Solution treatment: Heated at 800 ° C. for 3 minutes and cooled with water. Here, the heating time is the time until the water cooling starts after the material temperature reaches 800 ° C.
(E) Cold rolling: processed to a thickness of 0.5 mm.
(F) Aging treatment: Aging treatment was performed for 3 hours at a temperature at which the 0.2% yield strength was maximized. This temperature was in the range of 400-600 ° C.

これらの試料について０．２％耐力、Ｗ曲げ加工性、結晶方位および結晶粒径を下記要領で調査した。その結果を表１に示す。なお、集積度および結晶粒の形態はいずれの試料もＩ_{（２２０）}／Ｉ_{０（２２０）}＝１．０〜３．０、ｂ／ａ＝０．５〜０．７、およびａ＝３μｍ〜５μｍの範囲であった。
＜０．２％耐力＞引張試験機により圧延方向と平行な方向における耐力を測定した。
＜Ｗ曲げ加工性＞Ｗ曲げ試験（ＪＩＳＨ３１３０）にて、幅１０ｍｍ×長さ３０ｍｍの短冊を用いて行った。試験片採取方向は、ＧｏｏｄＷａｙおよびＢａｄＷａｙとし、割れの発生しない最小曲げ半径ＭＢＲ（ＭｉｎｉｍｕｍＢｅｎｄＲａｄｉｕｓ）と板厚ｔの比ＭＢＲ／ｔにて評価した。
＜板面方位指数＞（株）リガク製ＲＩＮＴ２５００を使用し、Ｘ線回折法により３つの（ｈｋｌ）面のＸ線回折強度Ｉ_{（ｈｋｌ）}を測定し、（式１）の値を求めた。なお、Ｘ線照射条件はＣｏ管球を使用し、管電圧２５ＫＶ、管電流２０ｍＡとした。
＜集積度＞（株）リガク製ＲＩＮＴ２５００を使用し、Ｘ線回折法により、（２２０）面のＸ線回折強度Ｉ_{（２２０）}および純銅粉末標準試料の（２２０）面のＸ線回折強度Ｉ_{０（２２０）}を測定し、集積度Ｉ_{（２２０）}／Ｉ_{０（２２０）}を求めた。なお、Ｘ線照射条件はＣｏ管球を使用し、管電圧２５ＫＶ、管電流２０ｍＡとした。
＜結晶粒径＞切断法（ＪＩＳＨ０５０１）にて、圧延方向に直角な断面における結晶粒の幅方向の平均長さをａ、厚み方向の平均長さをｂとし、ａおよびｂ／ａを求めた。 About these samples, 0.2% yield strength, W bending workability, crystal orientation, and crystal grain size were investigated as follows. The results are shown in Table 1. It should be noted that the degree of integration and the form of crystal grains are I ₍₂₂₀₎ / I _{0 (220)} = 1.0 to 3.0, b / a = 0.5 to 0.7, and a = 3 μm to any sample. The range was 5 μm.
<0.2% yield strength> The yield strength in a direction parallel to the rolling direction was measured by a tensile tester.
<W bending workability> In a W bending test (JIS H 3130), a strip having a width of 10 mm and a length of 30 mm was used. The specimen collection direction was set to Good Way and Bad Way, and evaluation was performed based on a ratio MBR / t of a minimum bending radius MBR (Minimum Bend Radius) and a thickness t where no cracks occurred.
<Plate surface orientation index> Using RINT2500 manufactured by Rigaku Corporation, the X-ray diffraction intensity I _(hkl) of three (hkl) planes was measured by the X-ray diffraction method, and the value of (Equation 1) was determined. The X-ray irradiation conditions were a Co tube, tube voltage 25 KV, tube current 20 mA.
<Degree of Integration> Using RINT2500 manufactured by Rigaku Corporation, by X-ray diffraction method, X-ray diffraction intensity I ₍₂₂₀₎ of (220) plane and X-ray diffraction intensity I ₀ of (220) plane of pure copper powder standard sample ₍₂₂₀₎ was measured, and the degree of integration I ₍₂₂₀₎ / I _{0 (220)} was determined. The X-ray irradiation conditions were a Co tube, tube voltage 25 KV, tube current 20 mA.
<Crystal grain size> Using the cutting method (JISH0501), a and b / a were determined by assuming that the average length in the width direction of the crystal grains in the cross section perpendicular to the rolling direction was a and the average length in the thickness direction was b. .

熱間圧延中の材料温度が高い発明例Ｎｏ．１〜Ｎｏ．４は、板面方位指数が、（式１）の範囲内であり、曲げ加工性はＧｏｏｄＷａｙおよびＢａｄＷａｙともに良好で、曲げの異方性が小さかった。０．２％耐力は、熱間圧延開始温度が低いほど高い傾向があった。一方、熱間圧延温度が低い比較例Ｎｏ．５およびＮｏ．６は、０．２％耐力は高いが、板面方位指数が（式１）の範囲外であり、ＧｏｏｄＷａｙの曲げ加工性が悪く、曲げ異方性が大きかった。
比較例Ｎｏ．７は、熱間圧延開始温度は高いが、圧延中の再加熱を施していないので、材料温度が低くなり、板面方位指数が（式1）の範囲から大きく外れた。０．２％耐力が同等の比較例Ｎｏ．６に対し、ＧｏｏｄＷａｙの曲げ加工性が悪化し、曲げの異方性がさらに大きくなった。 Invention Example No. with high material temperature during hot rolling 1-No. In No. 4, the plate surface orientation index was in the range of (Expression 1), the bending workability was good for both Good Way and Bad Way, and the bending anisotropy was small. The 0.2% yield strength tended to be higher as the hot rolling start temperature was lower. On the other hand, comparative example No. with a low hot rolling temperature. 5 and no. No. 6 had a high 0.2% proof stress, but the plate surface orientation index was outside the range of (Equation 1), the Good Way bending workability was poor, and the bending anisotropy was large.
Comparative Example No. In No. 7, the hot rolling start temperature was high, but since reheating was not performed during rolling, the material temperature was low, and the plate surface orientation index deviated significantly from the range of (Equation 1). Comparative Example No. with equivalent 0.2% proof stress On the other hand, the bending workability of Good Way was deteriorated, and the bending anisotropy was further increased.

（２）実施例２
次に、最終圧延加工度および溶体化処理の条件を変えたときの本発明の実施例について比較例とともに説明する。
電気銅を原料とし、大気溶解炉を用いてＣｕ−１．７±０．１％Ｎｉ−０．３５±０．０１％Ｓｉ−０．５±０．０１％Ｓｎ−０．４±０．０１％Ｚｎの銅合金を溶製し、厚さ２０ｍｍ×幅６０ｍｍのインゴットに鋳造した。このインゴットを次の工程で加工した。
（ａ）熱間圧延：９５０℃で３時間の均質化焼鈍を行った後、厚さ１５ｍｍ、１０ｍｍ、５ｍｍで９５０℃で再加熱しながら、板厚３ｍｍまで熱間圧延を行った。
（ｂ）面削：グラインダー研磨により表面スケールを除去した。
（ｃ）冷間圧延：厚さ０．６２５ｍｍまで加工した。
（ｄ）溶体化処理：所定温度にて所定時間加熱して水冷した。ここで、加熱時間は、材料温度が８００℃に達した後、水冷を開始するまでの時間であり、時間０ｍｉｎとは所定温度に到達直後に水冷を開始したことを示す。
（ｅ）冷間圧延：種々の加工度で圧延を行った。ここで、加工度ｒは次式で定義する。
ｒ＝（ｔ_０−ｔ）／ｔ_０×１００（ｔ_０：圧延前の板厚、ｔ：圧延後の板厚）
（ｆ）時効処理：０．２％耐力が最大となる温度で３時間の時効処理を行った。この温度は４００〜６００℃の範囲であった。
これらの試料について０．２％耐力、Ｗ曲げ加工性、板面方位指数、集積度、結晶粒形態を前述の要領で調査した。その結果を表２に示す。 (2) Example 2
Next, examples of the present invention when the final rolling degree and the solution treatment conditions are changed will be described together with comparative examples.
Using copper as a raw material and using an atmospheric melting furnace, Cu-1.7 ± 0.1% Ni-0.35 ± 0.01% Si-0.5 ± 0.01% Sn-0.4 ± 0. A copper alloy of 01% Zn was melted and cast into an ingot having a thickness of 20 mm and a width of 60 mm. This ingot was processed in the next step.
(A) Hot rolling: After performing homogenization annealing at 950 ° C. for 3 hours, hot rolling was performed to a plate thickness of 3 mm while reheating at 950 ° C. at a thickness of 15 mm, 10 mm, and 5 mm.
(B) Chamfering: The surface scale was removed by grinder polishing.
(C) Cold rolling: processed to a thickness of 0.625 mm.
(D) Solution treatment: Heated at a predetermined temperature for a predetermined time and cooled with water. Here, the heating time is the time until the water cooling starts after the material temperature reaches 800 ° C. The time 0 min indicates that the water cooling started immediately after reaching the predetermined temperature.
(E) Cold rolling: Rolling was performed at various working degrees. Here, the processing degree r is defined by the following equation.
r = (t ₀ −t) / t ₀ × 100 (t ₀ : plate thickness before rolling, t: plate thickness after rolling)
(F) Aging treatment: Aging treatment was performed for 3 hours at a temperature at which the 0.2% yield strength was maximized. This temperature was in the range of 400-600 ° C.
With respect to these samples, 0.2% proof stress, W bending workability, plate surface orientation index, degree of integration, and crystal grain morphology were examined as described above. The results are shown in Table 2.

発明例Ｎｏ．８〜Ｎｏ．１１は、板面方位指数、集積度および結晶粒形態が（式１）、（式２）および（式３）の範囲内であり、曲げ加工性および異方性が優れていた。
比較例Ｎｏ．１２は、溶体化温度が高かったので、集積度が（式２）の範囲外であった。さらに、結晶粒径が粗大で、ａの値が（式３）の範囲外であった。同じ加工度の発明例Ｎｏ．９より０．２％耐力が低いにもかかわらず、ＧｏｏｄＷａｙ、ＢａｄＷａｙの曲げ加工性とも劣った。
比較例Ｎｏ．１３は、溶体化温度が低かったので溶体化が不充分であり、また、再結晶せずに圧延組織が残ったままで、結晶粒形態を測定できなかった。同じ加工度の発明例Ｎｏ．９より強度が低いにもかかわらず、ＧｏｏｄＷａｙ、ＢａｄＷａｙの曲げ加工性とも劣り、特にＢａｄＷａｙの曲げ加工性が悪かった。 Invention Example No. 8-No. No. 11 had a plate surface orientation index, an integration degree, and a crystal grain form within the range of (Formula 1), (Formula 2) and (Formula 3), and was excellent in bending workability and anisotropy.
Comparative Example No. No. 12, because the solution temperature was high, the degree of accumulation was outside the range of (Equation 2). Furthermore, the crystal grain size was coarse, and the value of a was outside the range of (Formula 3). Invention Example No. having the same degree of processing Although the 0.2% yield strength was lower than 9, Good Way and Bad Way were also inferior in bending workability.
Comparative Example No. In No. 13, since the solution temperature was low, the solution formation was insufficient, and the crystal grain morphology could not be measured while the rolling structure remained without recrystallization. Invention Example No. having the same degree of processing Although the strength was lower than 9, the bending workability of Good Way and Bad Way was also inferior, and the bending workability of Bad Way was particularly bad.

比較例Ｎｏ．１４は溶体化時間が短かかったので結晶粒が小さく、aの値が（式３）の範囲外となった。同じ加工度の発明例Ｎｏ．９より強度が低いにもかかわらず、ＧｏｏｄＷａｙ、ＢａｄＷａｙの曲げ加工性とも劣った。
比較例Ｎｏ．１５は溶体化時間が長いので、結晶粒径が大きく、 aの値が（式３）の範囲外になり、また、集積度が（式２）の範囲外となった。同じ加工度の発明例Ｎｏ．９より強度が低くいにもかかわらず、ＧｏｏｄＷａｙ、ＢａｄＷａｙの曲げ加工性とも劣った。 Comparative Example No. No. 14 had a short solution time, so the crystal grains were small, and the value of a was outside the range of (Equation 3). Invention Example No. having the same degree of processing Although the strength was lower than 9, Good Way and Bad Way were also inferior in bending workability.
Comparative Example No. No. 15 had a long solution time, so the crystal grain size was large, the value of a was outside the range of (Formula 3), and the degree of integration was outside the range of (Formula 2). Invention Example No. having the same degree of processing Although the strength was lower than 9, Good Way and Bad Way were also inferior in bending workability.

比較例Ｎｏ．１６は、最終圧延を行わなかったので、強度が低くなり、板面方位指数、（２２０）面の集積度およびａ／ｂの値が範囲外であった。発明例Ｎｏ．８より強度が８３ＭＰａ低かったがＧｏｏｄ
Ｗａｙの曲げ加工性が悪かった。
比較例Ｎｏ．１７は、最終圧延加工度が高いので集積度が範囲外で、さらに、高加工度の最終圧延により結晶粒が著しく歪んでいたため結晶粒形態を測定できなかった。強度が近い発明例Ｎｏ．１１よりＧｏｏｄＷａｙ、ＢａｄＷａｙの曲げ加工性とも劣った。
なお、比較例Ｎｏ．１６を除き、曲げの逆異方性は、板面方位指数が（式２）の範囲内であったため小さかった。 Comparative Example No. In No. 16, since the final rolling was not performed, the strength was low, and the plate surface orientation index, the (220) plane integration degree, and the value of a / b were out of range. Invention Example No. The strength was 83MPa lower than 8, but Good
The bending workability of the way was poor.
Comparative Example No. In No. 17, the degree of integration was out of the range because the final rolling degree was high, and the crystal grains could not be measured because the crystal grains were significantly distorted by the final rolling with a high degree of working. Invention Example No. with close strength 11 was also inferior in the bending workability of Good Way and Bad Way.
Comparative Example No. Except for 16, the reverse anisotropy of bending was small because the plate surface orientation index was within the range of (Equation 2).

切断法（ＪＩＳＨ０５０１）によって結晶粒形態を求める原理を示す説明図である。It is explanatory drawing which shows the principle which calculates | requires a crystal grain form by the cutting method (JISH0501).

Claims

Ｎｉを１．０〜４．５質量％（以下％とする）、Ｓｉを０．２５〜１．５％含有し、残部がＣｕおよび不可避的不純物よりなる銅基合金の圧延面においてＸ線回折を用いて測定した３つの（ｈｋｌ）面のＸ線回折強度が、
（Ｉ_{（１１１）}＋Ｉ_{（３１１）}）／Ｉ_{（２２０）}≦２．０
を満足することを特徴とする高強度および高曲げ加工性を両立させたＣｕ−Ｎｉ−Ｓｉ系銅合金条。 X-ray diffraction on the rolling surface of a copper-based alloy containing 1.0 to 4.5% by mass (hereinafter referred to as%) of Ni, 0.25 to 1.5% of Si, and the balance of Cu and inevitable impurities X-ray diffraction intensities of three (hkl) planes measured using
(I ₍₁₁₁₎ + I ₍₃₁₁₎ ) / I ₍₂₂₀₎ ≦ 2.0
A Cu—Ni—Si based copper alloy strip having both high strength and high bending workability characterized by satisfying

圧延面においてＸ線回折を用いて測定した（２２０）面のＸ線回折強度をＩ_{（２２０）}、および純銅粉末標準試料においてＸ線回折を用いて測定した（２２０）面のＸ線回折強度をＩ_{０（２２０）}としたときの、Ｉ_{（２２０）}／Ｉ_{０（２２０）}が、
１.０≦Ｉ_{（２２０）}/Ｉ_{０（２２０）}≦３．０
を満足することを特徴とする請求項１に記載のＣｕ−Ｎｉ−Ｓｉ系銅合金条。 The X-ray diffraction intensity of the (220) plane measured using X-ray diffraction on the rolled surface is I ₍₂₂₀₎ , and the X-ray diffraction intensity of the (220) plane measured using X-ray diffraction on a pure copper powder standard sample when formed into a _{_{I 0 (220), I (}} 220) / I 0 is _(220),
1.0 ≦ I ₍₂₂₀₎ / I _{0 (220)} ≦ 3.0
The Cu—Ni—Si based copper alloy strip according to claim 1, wherein:

圧延方向に直角な断面における結晶粒の幅方向の平均長さをａ、厚み方向の平均長さをｂとしたときに、
０．５≦ｂ／ａ≦０．９
２μｍ≦ａ≦２０μｍ
であることを特徴とする請求項１または２に記載のＣｕ−Ｎｉ−Ｓｉ系銅合金条。 When the average length in the width direction of the crystal grains in the cross section perpendicular to the rolling direction is a and the average length in the thickness direction is b,
0.5 ≦ b / a ≦ 0.9
2μm ≦ a ≦ 20μm
The Cu—Ni—Si based copper alloy strip according to claim 1, wherein the strip is a Cu—Ni—Si based copper alloy strip.

Ｍｇを０．０５〜０．３％含有することを特徴とする請求項１〜３のいずれかに記載のＣｕ−Ｎｉ−Ｓｉ系銅合金条。 The Cu—Ni—Si based copper alloy strip according to claim 1, containing 0.05 to 0.3% of Mg.

Ｚｎ、Ｓｎ、Ｆｅ、Ｔｉ、Ｚｒ、Ｃｒ、Ａｌ、Ｐ、Ｍｎ、Ａｇ、またはＢｅのうち１種類以上を総量で０．００５〜２．０％含有することを特徴とする請求項１〜４のいずれかに記載のＣｕ−Ｎｉ−Ｓｉ系銅合金条。

The total content of one or more of Zn, Sn, Fe, Ti, Zr, Cr, Al, P, Mn, Ag, or Be is 0.005 to 2.0%. Cu-Ni-Si system copper alloy strip in any one of above.