JP4984108B2 - Cu-Ni-Sn-P based copper alloy with good press punchability and method for producing the same - Google Patents

Description

本発明は、コネクタ等の通電部品に適したＣｕ−Ｎｉ−Ｓｎ−Ｐ系銅合金およびその製造法に関する。   The present invention relates to a Cu—Ni—Sn—P based copper alloy suitable for current-carrying parts such as connectors and a method for producing the same.

近年のエレクトロニクスの発達により、電気・電子機器の電気配線は複雑化・高集積化が進み、コネクタ等の通電部品には小型化、軽量化、高信頼性化、低コスト化の要求が高まっている。それに伴いコネクタ等の部品に使用される素材は、従来にも増して薄肉化され、かつ複雑な形状にプレス成形されるようになっている。このため素材特性としては強度、弾性、導電性および加工性のすべてが良好でなければならない。さらに、部品の信頼性を向上させるうえで耐応力緩和特性に優れることも重要である。   With the recent development of electronics, the electrical wiring of electrical and electronic equipment has become more complex and highly integrated, and there is a growing demand for smaller, lighter, more reliable, and lower cost electrical parts such as connectors. Yes. Along with this, materials used for parts such as connectors are thinner than ever and are press-molded into complicated shapes. For this reason, the material properties must all be good in strength, elasticity, conductivity and workability. Furthermore, it is important to have excellent stress relaxation characteristics in order to improve the reliability of the parts.

これらの各特性を比較的バランス良く実現しやすい素材としてＣｕ−Ｎｉ−Ｓｎ−Ｐ系銅合金が挙げられる。この合金はＮｉ−Ｐ系の析出物を微細分散させることで各種特性の改善を図ることができ、これまでに電気・電子部品用に適したものが種々開発されている（特許文献１〜８）。   A Cu—Ni—Sn—P-based copper alloy is a material that can easily realize these characteristics in a relatively balanced manner. Various characteristics of this alloy can be improved by finely dispersing Ni-P-based precipitates, and various alloys suitable for electric and electronic parts have been developed so far (Patent Documents 1 to 8). ).

特開平４−１５４９４２号公報Japanese Patent Laid-Open No. 4-154944 特開平４−２３６７３６号公報Japanese Patent Laid-Open No. 4-236736 特開平１０−２２６８３５号公報Japanese Patent Laid-Open No. 10-226835 特開２０００−１２９３７７号公報JP 2000-129377 A 特開２０００−２５６８１４号公報JP 2000-256814 A 特開２００１−２６２２５５号公報JP 2001-262255 A 特開２００１−２６２２９７号公報JP 2001-262297 A 特開２００２−２９４３６８号公報JP 2002-294368 A 特開２００１−１５２３０３号公報JP 2001-152303 A 特開２００２−１８０１６５号公報JP 2002-180165 A 特開平１１−３４３５２７号公報JP-A-11-343527 特開２００２−１９４４６１号公報JP 2002-194461 A

コネクタ等の通電部品は板状素材をプレス成形して作られるが、例えば自動車用の端子では、バスバーに用いられる音叉端子やプレスフィット端子等、プレス打抜き面が接触面になるようにばね成形する部品が増えている。板厚の薄い民生部品でも同様で、例えばパソコンのＤＩＭＭコネクター等はプレス打抜き面が端子の接触面になるよう設計されることがある。これらの部品ではプレス打抜き面のダレ、バリが少なく、かつせん断面と破断面の段差が小さいこと、つまり、プレス打抜き面が平坦でかつ広い接触面積が得られることが求められる。
さらに、部品の生産性を向上させ製造コストを下げるためには、高速のプレス加工が可能で、かつ金型の摩耗が少なく、金型のメンテナンス負荷が小さいことが望まれるが、プレス打抜き面のせん断面と破断面の段差が大きい場合は、打抜き後の部品が金型に詰まり、これが連続プレスで重なることにより、金型のクリアランスを変化させることがあり、金型のメンテナンス負荷が大きくなるため、より打抜き面の段差を小さく保つことができる材料が望まれていた。 Current-carrying parts such as connectors are made by press-molding a plate-shaped material. For example, in automobile terminals, spring-molded parts such as tuning fork terminals and press-fit terminals used for bus bars are made to be contact surfaces. The parts are increasing. The same applies to consumer parts with thin plate thickness. For example, a DIMM connector of a personal computer may be designed so that the press punched surface becomes the contact surface of the terminal. These parts are required to be free from sagging and burrs on the press punched surface, to have a small step between the shear surface and the fracture surface, that is, to have a flat press punched surface and a wide contact area.
Furthermore, in order to improve the productivity of parts and reduce the manufacturing cost, it is desirable that high-speed press processing is possible, the mold wear is low, and the mold maintenance load is small. If there is a large difference between the shearing surface and the fracture surface, the stamped parts will clog the mold, and this may overlap with the continuous press, which may change the mold clearance, increasing the mold maintenance load. Therefore, there has been a demand for a material that can keep the step of the punched surface smaller.

このように、コネクタ等の通電部品に用いる素材にとって、プレス打抜き性は重要な特性の１つとなっている。しかしながら、Ｃｕ−Ｎｉ−Ｓｎ−Ｐ系銅合金においてプレス打抜き性を第１優先とした組織を得ようとすると、強度、曲げ加工性、耐応力緩和特性といった基本特性が低下してしまうという問題がある。特許文献１〜８に示されるような従来のＣｕ−Ｎｉ−Ｓｎ−Ｐ系銅合金はプレス打抜き性に対して特段の配慮がなされておらず、昨今の部品ニーズに十分応えることができない。   Thus, press punchability is one of the important characteristics for materials used for current-carrying parts such as connectors. However, there is a problem in that basic characteristics such as strength, bending workability, and stress relaxation resistance are lowered when an attempt is made to obtain a structure in which press punchability is the first priority in a Cu—Ni—Sn—P based copper alloy. is there. Conventional Cu—Ni—Sn—P based copper alloys as shown in Patent Documents 1 to 8 do not give special consideration to press punchability and cannot sufficiently meet the recent needs for parts.

一方、銅合金のプレス打抜き性を改善する手段として、集合組織を制御することも行われている（特許文献９、１０）。しかし、集合組織を制御するには冷間圧延率や熱処理温度等の製造条件が大きく制約され、製造性の低下を伴うだけでなく、曲げ加工性や耐応力緩和特性といった、プレス打抜き性とトレードオフする特性が現れ、上記の諸特性をバランス良く付与すること自体も困難となる。   On the other hand, as a means for improving the press punchability of a copper alloy, the texture is also controlled (Patent Documents 9 and 10). However, to control the texture, manufacturing conditions such as the cold rolling rate and heat treatment temperature are greatly restricted, which not only leads to a decrease in manufacturability but also trade-off with press punchability such as bending workability and stress relaxation resistance. A characteristic of turning off appears, and it is difficult to provide the above characteristics in a well-balanced manner.

打抜き加工で発生する残留応力が小さく、また残留応力の除去がしやすい銅合金や、ダレ、バリの小さいリードフレーム用銅合金も開発されているが（特許文献１１、１２）、これらの技術では、打抜き加工時の残留応力の軽減に有効であっても、プレス打抜き面におけるせん断面と破断面の段差を低減させることが十分に実現できず、より効果的な対策が望まれていた。   A copper alloy that has a small residual stress generated by punching and is easy to remove the residual stress, and a copper alloy for a lead frame with small sagging and burrs have been developed (Patent Documents 11 and 12). Even if it is effective in reducing the residual stress at the time of punching, it is not possible to sufficiently reduce the level difference between the shear surface and the fracture surface on the press punched surface, and a more effective countermeasure has been desired.

本発明は、Ｃｕ−Ｎｉ−Ｓｎ−Ｐ系銅合金において、通電部品素材として従来から必要であるとされている特性、すなわち強度、導電性、曲げ加工性、耐応力緩和特性、はんだ耐候性等の基本特性を高く維持したまま、優れたプレス打抜き性を付与したものを提供することを目的とする。   In the Cu-Ni-Sn-P based copper alloy, the present invention has characteristics conventionally required as a current-carrying component material, that is, strength, conductivity, bending workability, stress relaxation resistance, solder weather resistance, etc. An object of the present invention is to provide a material having excellent press punchability while maintaining the basic characteristics of the above.

発明者らの検討の結果、上記目的は、微細析出物と比較的大きな析出物とが混在する特異な析出形態を実現することによって達成できることを見出した。
すなわち本発明では、質量％でＮｉ：０.１５〜１.５％、Ｓｎ：０.１〜２.３％、Ｐ：０.０２〜０.２％を含み、さらに必要に応じてＺｎ：５％以下、Ｃｏ：０.３％以下、Ｍｎ：０.３％以下、Ｆｅ：０.３％以下およびＭｇ：０.１５％以下のうち１種または２種以上を含み、好ましくはＡｌ、Ｔｉ、Ｓｉの合計含有量が０.００１質量％以下で、残部がＣｕおよび不可避的不純物からなる組成を有し、粒径２０ｎｍ未満の微細析出物が分散して存在するとともに、粒径２０〜１５０ｎｍの析出物が１.５×１０⁶ｎｍ²あたり０.３〜３０個の密度で存在し、粒径１５０ｎｍを超える粗大析出物が存在しないか、または１.５×１０⁶ｎｍ²あたり３個以下の密度に抑えられている組織を有するプレス打抜き性に優れた銅合金が提供される。 As a result of investigations by the inventors, it has been found that the above object can be achieved by realizing a unique precipitation form in which fine precipitates and relatively large precipitates are mixed.
That is, according to the present invention, Ni includes 0.15 to 1.5%, Sn: 0.1 to 2.3%, and P: 0.02 to 0.2% in mass%, and further includes Zn: 5% or less, Co: 0.3% or less, Mn: 0.3% or less, Fe: 0.3% or less, and Mg: 0.15% or less, preferably one or more, preferably Al, Ti, a total content of under 0.001 wt% or less of Si, have the balance consisting of Cu and unavoidable impurities, with fine precipitates having a particle size of less than 20nm is present in a dispersed particle size 20 It precipitates ~150nm is present in 0.3 to 30 pieces of density per ² 1.5 × 10 ⁶ nm, or no coarse precipitates exceeding a particle size 150 nm, or 1.5 × 10 ⁶ nm per ² A copper alloy having a structure in which the density is suppressed to 3 or less and excellent in press punchability is provided.

ここで、析出物の粒径は長径を意味する。上記各析出物の存在は透過型電子顕微鏡（ＴＥＭ）観察によって把握される。「微細析出物が分散して存在している」とは、当該析出物がマトリクス中に多数分布していることが観察される状態である。１.５×１０⁶ｎｍ²あたりの析出物の密度は、透過型電子顕微鏡を用いて所定粒径範囲の析出物の数を測定し、１.５×１０⁶ｎｍ²を単位面積として、その単位面積あたりに存在する析出物の平均個数を算出したものに相当する。その場合、観察領域の合計面積は少なくとも単位面積の２倍以上とする。具体的には加速電圧２００ｋＶ、倍率５００００倍の明視野像においてフォーカスを固定した状態で存在が確認される析出物を対象として、所定の粒径をもつ析出物粒子の数をカウントする。個々の粒子について粒径が所定の範囲にあるかどうかを確認するためには倍率を上げてフォーカスを合わせる操作やステージを傾斜させる操作を行うことができる。そして、カウントされたトータル個数に「単位面積／観察領域の合計面積」の値を乗じることにより、単位面積あたりの析出物の密度が算出される。 Here, the particle size of the precipitates means the major axis. The presence of each of the precipitates is grasped by observation with a transmission electron microscope (TEM). “The fine precipitates are dispersed and present” means that a large number of the precipitates are observed distributed in the matrix. The density of precipitates per 1.5 × 10 ⁶ nm ² is determined by measuring the number of precipitates in a predetermined particle size range using a transmission electron microscope, and taking 1.5 × 10 ⁶ nm ² as a unit area. This corresponds to the calculation of the average number of precipitates present around. In that case, the total area of the observation region is at least twice the unit area. Specifically, the number of precipitate particles having a predetermined particle size is counted for precipitates whose existence is confirmed in a bright field image with an acceleration voltage of 200 kV and a magnification of 50000 times in a fixed state. In order to confirm whether or not the particle size is within a predetermined range for each particle, an operation of adjusting the focus by increasing the magnification or an operation of tilting the stage can be performed. Then, the density of precipitates per unit area is calculated by multiplying the counted total number by the value of “unit area / total area of observation region”.

また本発明ではこのような組織状態を有するプレス打抜き性に優れた銅合金の効果的な製造法として、上記組成の銅合金を溶解した後、鋳造、熱間圧延、および１回以上の「冷間圧延、焼鈍」を含む製造工程において、鋳造時に７００〜４００℃の平均冷却速度を３０℃／ｍｉｎ以上とし、熱間圧延時に材料を８５０〜９６０℃の炉中に装入し、材料全体が７００℃以上になってから２時間以上、８００℃以上になってから１時間以上保持したのち炉から抽出して熱間圧延を行い、材料温度が７００〜４００℃にある時間を２０ｓｅｃ〜３０ｍｉｎの範囲で確保するとともに７００℃以下の温度域で１パス以上の圧下を行う製造法が提供される。 Further, in the present invention, as an effective method for producing a copper alloy having such a textured state and excellent in press punchability, after melting the copper alloy having the above composition, casting, hot rolling, and one or more “cooling” In the manufacturing process including “rolling and annealing”, the average cooling rate of 700 to 400 ° C. is set to 30 ° C./min or more during casting, and the material is charged into a furnace of 850 to 960 ° C. during hot rolling. Hold for 2 hours or more after becoming 700 ° C or more, hold for 1 hour or more after becoming 800 ° C or more, then extract from the furnace, perform hot rolling, and set the material temperature at 700 to 400 ° C for 20 sec to 30 min. Provided is a manufacturing method that secures a range and performs a reduction of one pass or more in a temperature range of 700 ° C. or lower .

熱間圧延工程は、大きく「加熱」、「圧延」、「冷却」の過程からなり、「圧延」の途中で「中間加熱」が挿入される場合もある。上記「熱間圧延時」とは熱間圧延工程の最初の「加熱」を終えた後、「冷却」が終わるまでをいう。７００〜４００℃の温度域で１パス以上の圧下が行われる場合、その圧下が行われている時間も「材料温度が７００〜４００℃にある時間」場合に含まれる。   The hot rolling process is largely composed of processes of “heating”, “rolling”, and “cooling”, and “intermediate heating” may be inserted in the middle of “rolling”. The “at the time of hot rolling” refers to the time from the completion of the first “heating” in the hot rolling process to the end of “cooling”. In the case where a reduction of one pass or more is performed in a temperature range of 700 to 400 ° C., the time during which the reduction is performed is also included in the “time when the material temperature is 700 to 400 ° C.”.

本発明によれば、従来からコネクタ等の通電部品用素材として実績のあるＣｕ−Ｎｉ−Ｓｎ−Ｐ系銅合金において、優れたプレス打抜き性を付与することが可能になった。その際、強度、導電性、曲げ加工性、耐応力緩和特性、はんだ耐候性等の基本特性は高く維持される。したがって本発明は、小型化、薄肉化が進展するコネクタ等の通電部品において、プレス打抜き面を接触面とする通電性能を向上させることができ、昨今の電気・電子部品ニーズに応えるものである。   According to the present invention, it has become possible to impart excellent press punchability to a Cu—Ni—Sn—P based copper alloy that has been proven as a material for current-carrying parts such as connectors. At that time, basic characteristics such as strength, conductivity, bending workability, stress relaxation resistance and solder weather resistance are maintained high. Therefore, the present invention can improve the current-carrying performance using the press punched surface as a contact surface in current-carrying parts such as connectors, which are becoming smaller and thinner, and responds to recent needs for electric and electronic parts.

本発明では、サイズの異なる２種類のタイプのＮｉ−Ｐ系析出物が混在している特異な析出物分布形態を実現することによって前記の種々の特性を同時に改善する。
具体的には、粒径が微細なタイプの析出物をマトリクス中に多数分散させることによって、強度、導電性、曲げ加工性、耐応力緩和特性といった通電部品用素材に必要な基本特性を付与する。ただし、これらの特性の向上に寄与するような微細なサイズの析出物は、プレス打抜き性を向上させる作用が少ない。 In the present invention, the above-mentioned various characteristics are simultaneously improved by realizing a unique precipitate distribution form in which two types of Ni-P-based precipitates having different sizes are mixed.
Specifically, by dispersing a large number of fine particle size type precipitates in the matrix, the basic characteristics necessary for the current-carrying component materials such as strength, conductivity, bending workability, and stress relaxation resistance are imparted. . However, fine precipitates that contribute to the improvement of these properties have little effect of improving press punchability.

そこで、より粒径が大きいタイプの析出物を同時に分散させる。このタイプの析出物粒子は、プレス打抜き時にクラックの発生源として機能し、ダレの増大を防止する。そして、この粒径が大きいタイプの析出物が所定の密度で分散して存在しているとき、発生したクラックが各析出物粒子の間を伝播することにより容易に破壊が起こり、打抜き面の平坦性が向上する。さらに、ダレの少ない破壊が容易に起こることによってプレス金型の摩耗も顕著に軽減される。   Therefore, a precipitate having a larger particle size is simultaneously dispersed. This type of precipitate particles functions as a source of cracks during press punching and prevents an increase in sagging. And when this type of precipitate with a large particle size is dispersed and present at a predetermined density, the generated crack propagates between the respective precipitate particles, so that breakage easily occurs and the punched surface is flat. Improves. Furthermore, wear of the press die is remarkably reduced by easily causing breakage with less sagging.

強度、曲げ加工性、耐応力緩和特性等の基本特性の向上に寄与する微細なタイプの析出物は、粒径が２０ｎｍ未満であることが必要である。これより大きいと上記特性の向上が不十分となる。１０ｎｍ以下の非常に微細な析出物が分散していることが一層望ましい。これらの粒径２０ｎｍ未満の微細なサイズの析出物は、応力緩和特性を得るために、前記１.５×１０⁶ｎｍ²あたりの析出物量として１００個以上であることが望ましい。 The fine type precipitates that contribute to the improvement of basic properties such as strength, bending workability, and stress relaxation resistance must have a particle size of less than 20 nm. If it is larger than this, the improvement of the above characteristics becomes insufficient. More desirably, very fine precipitates of 10 nm or less are dispersed. These fine precipitates having a particle size of less than 20 nm are desirably 100 or more precipitates per 1.5 × 10 ⁶ nm ^{2 in} order to obtain stress relaxation characteristics.

プレス打抜き性の向上をもたらす粒径の大きいタイプの析出物としては、粒径２０〜１５０ｎｍのものが必要である。このようなサイズの析出物はマトリクスとの整合性が低下するため強度面への寄与は少なくなる。析出物の粒径が２０ｎｍに満たないと上述のプレス打抜き性を向上させる機能が十分発揮されない。粒径が１５０ｎｍを超えるような粗大な析出物は曲げ加工時のクラックの起点となりやすく、曲げ加工性を低下させることがある。したがって本発明では粒径２０〜１５０ｎｍの範囲にある析出物によってプレス打抜き性の改善を図る。   As a precipitate having a large particle size that brings about improved press punchability, a precipitate having a particle size of 20 to 150 nm is required. A precipitate having such a size is less consistent with the matrix and therefore contributes less to the strength. If the particle size of the precipitate is less than 20 nm, the function of improving the press punchability described above cannot be exhibited sufficiently. Coarse precipitates having a particle size exceeding 150 nm tend to be the starting point of cracks during bending, and may reduce bending workability. Therefore, in the present invention, the press punchability is improved by the precipitate having a particle size in the range of 20 to 150 nm.

粒径２０〜１５０ｎｍの析出物の存在量としては、１.５×１０⁶ｎｍ²あたり０.３〜３０個の密度とすることが必要である。これより少ないとプレス打抜き面においてクラック発生の起点が少なくなり、かつクラック伝播作用も十分に発揮されないため、結果的にプレス打抜き性の向上は不十分となる。逆に上記を超えて存在量が多くなると、特に耐応力緩和特性の低下が目立つようになり、曲げ加工性も低下する。このタイプの析出物のより好ましい存在量は１.５×１０⁶ｎｍ²あたり１〜２０個の密度であり、通常１.５×１０⁶ｎｍ²あたり１〜１０個の密度で良好な結果が得られる。 The abundance of precipitates having a particle size of 20 to 150 nm needs to be a density of 0.3 to 30 per 1.5 × 10 ⁶ nm ² . If it is less than this, the starting point of crack generation on the press punched surface is reduced, and the crack propagation action is not sufficiently exhibited, and as a result, the press punchability is not sufficiently improved. On the other hand, if the abundance increases beyond the above, especially the stress relaxation resistance is conspicuous, and the bending workability is also lowered. More preferably abundance of this type of deposit is 1-20 density per ² 1.5 × 10 ⁶ nm, is usually 1.5 × 10 ⁶ nm ² per 1-10 density with good results can get.

粒径１５０ｎｍを超える粗大な析出物は上記のように曲げ加工性を低下させる要因となりやすいのでできるだけ少ないことが望ましい。具体的には粒径１５０ｎｍを超える粗大析出物は存在しない（観察されない）か、１.５×１０⁶ｎｍ²あたり３個以下の密度であることが望ましい。 Coarse precipitates having a particle size exceeding 150 nm are liable to cause a decrease in bending workability as described above, and therefore it is desirable that the amount be as small as possible. Specifically, it is desirable that there are no coarse precipitates having a particle size exceeding 150 nm (not observed) or a density of 3 or less per 1.5 × 10 ⁶ nm ² .

このようなサイズの異なる２つのタイプの析出物が混在した組織状態を実現し、かつ強度、導電性、曲げ加工性、耐応力緩和特性、プレス打抜き性等の特性を具備させるために、以下のような合金組成が採用される。   In order to realize a structure state in which two types of precipitates having different sizes are mixed and to have properties such as strength, conductivity, bending workability, stress relaxation resistance, and press punching properties, the following Such an alloy composition is employed.

〔Ｎｉ〕
Ｎｉは、Ｐと共添することにより本発明で重要な役割を担う２種類のタイプのＮｉ−Ｐ系析出物を形成する。また、固溶したＮｉは単体で、あるいは固溶したＳｎとの相互作用により、強度（ばね性）、耐応力緩和特性の向上をもたらす。これらの作用は０.１５質量％以上のＮｉ含有により発揮される。しかし、Ｎｉ含有量が多くなりすぎると導電性が低下するだけでなく、Ｎｉ−Ｐ系析出物の析出温度域が上昇するので析出物の粒径が大きくなりやすく、サイズ分布の適正化を図ることが難しくなる。また粒径１５０ｎｍを超える粗大析出物も生成しやすくなる。このような理由によりＮｉ含有量は０.１５〜１.５質量％とする必要があり、０.３〜１.２質量％とすることがより好ましく、０.５〜１.０質量％が一層好ましい。また、特に自動車のバスバーやソケット部品等、導電性を重視する用途ではＮｉ含有量を０.３〜０.８質量％にすることが好ましい。 [Ni]
Ni co-adds with P to form two types of Ni—P-based precipitates that play an important role in the present invention. In addition, solid solution Ni is improved in strength (spring property) and stress relaxation resistance due to single substance or interaction with solid solution Sn. These effects are exhibited by the Ni content of 0.15% by mass or more. However, if the Ni content is too high, not only the conductivity is lowered, but also the precipitation temperature range of the Ni-P-based precipitates is increased, so that the particle size of the precipitates is likely to increase, and the size distribution is optimized. It becomes difficult. In addition, coarse precipitates having a particle size exceeding 150 nm are easily generated. For these reasons, the Ni content must be 0.15 to 1.5% by mass, more preferably 0.3 to 1.2% by mass, and 0.5 to 1.0% by mass. Even more preferred. Moreover, it is preferable to make Ni content 0.3-0.8 mass% especially in the use which attaches importance to electroconductivity, such as a bus bar and socket components of a motor vehicle.

〔Ｓｎ〕
Ｓｎはマトリクス中に固溶し、強度、ビッカース硬さをはじめとする機械特性の向上をもたらす。また、固溶したＳｎとＮｉ−Ｐ系析出物の相互作用により、強度（ばね性）、耐応力緩和特性の向上効果が得られる。更に、プレス打抜き時の加工硬化量を増大させ、打抜き性の向上をもたらす。これらの作用を十分発揮させるには０.１質量％以上のＳｎ含有が必要である。しかし、Ｓｎ含有量が多くなりすぎると導電性の低下、熱間加工性の低下を招く。このためＳｎ含有量は０.１〜２.３質量％にする必要がある。ジャンクションボックス用のバスバー等、導電性を重視する用途に使用する場合は０.１〜０.６質量％のＳｎ含有量とすることが望ましく、０.１５〜０.３質量％とすることが一層好ましい。また、小型端子等の用途を考慮した場合は０.５〜２.０質量％のＳｎ含有が望ましく、０.７〜１.６質量％が一層好ましい。 [Sn]
Sn dissolves in the matrix and improves mechanical properties such as strength and Vickers hardness. In addition, an effect of improving strength (spring property) and stress relaxation resistance is obtained by the interaction between the solid solution Sn and the Ni-P-based precipitate. Further, the amount of work hardening at the time of press punching is increased, and the punchability is improved. In order to fully exhibit these actions, it is necessary to contain 0.1 mass% or more of Sn. However, if the Sn content is too high, the conductivity and hot workability are reduced. For this reason, Sn content needs to be 0.1-2.3 mass%. When used in applications where electrical conductivity is important, such as bus bars for junction boxes, the Sn content is preferably 0.1 to 0.6% by mass, and 0.15 to 0.3% by mass. Even more preferred. In consideration of applications such as small terminals, the Sn content is preferably 0.5 to 2.0% by mass, and more preferably 0.7 to 1.6% by mass.

〔Ｐ〕
Ｐは、上記ＮｉとともにＮｉ−Ｐ系析出物を形成し、前述の諸特性の向上に寄与する。Ｐ含有量が０.０２質量％未満ではプレス打抜き性を向上させる粒径２０〜１５０ｎｍの析出物が十分に得られないだけでなく、場合によっては強度や耐応力緩和特性等の向上に寄与する微細なタイプのＮｉ−Ｐ系析出物が十分な量だけ得られない。また、プレス打抜き性の向上に有効な粒径の大きいタイプのＮｉ−Ｐ系析出物を形成することが難しくなる。一方、Ｐ含有量が０.２質量％を超えると熱間加工性、冷間加工性が低下するだけでなく、粗大なＮｉ−Ｐ系析出物の生成を招きやすくなる。したがってＰ含有量は０.０２〜０.２質量％とする必要があり、０.０４〜０.１６質量％とすることがより好ましく、０.０５〜０.１質量％が一層好ましい。 [P]
P forms Ni—P-based precipitates together with the Ni, and contributes to the improvement of the above-described characteristics. When the P content is less than 0.02% by mass, not only a precipitate having a particle size of 20 to 150 nm that improves press punchability is obtained, but also contributes to improvement in strength, stress relaxation resistance, and the like. A sufficient amount of fine type Ni—P-based precipitates cannot be obtained. In addition, it becomes difficult to form Ni-P-based precipitates having a large particle size that are effective for improving press punchability. On the other hand, when the P content exceeds 0.2% by mass, not only hot workability and cold workability are lowered, but also the formation of coarse Ni—P-based precipitates is likely to occur. Therefore, the P content must be 0.02 to 0.2% by mass, more preferably 0.04 to 0.16% by mass, and even more preferably 0.05 to 0.1% by mass.

〔Ｎｉ／Ｐ〕
本発明ではＮｉ−Ｐ系析出物のサイズおよび量をコントロールすることで諸特性の同時改善を実現している。したがって添加されるＮｉとＰの量比を適正化することが望ましい。発明者らの検討によると、質量％によるＮｉ量とＰ量の比で表されるＮｉ／Ｐの値は２〜３０であることが望ましく、５〜２５であることが一層好ましい。Ｎｉ／Ｐが大きくなりすぎるとめっき密着性やはんだ耐候性の低下を招くとともに、析出物のサイズが大きくなりやすいことによりプレス打抜き性に寄与する粒径の大きいタイプの析出物の量が増大して曲げ加工性や耐応力緩和特性の低下を招きやすい。さらに粗大析出物の量も多くなる。逆にＮｉ／Ｐが小さすぎるとプレス打抜き性に寄与する粒径の大きいタイプの析出物が形成されにくくなる。この傾向はＰ量が多い場合に顕著になる。このため、Ｐ含有量が０.１質量％を超える場合はＮｉ／Ｐが５以上となるようにＮｉを前記許容範囲内で多めに添加することが望ましい。 [Ni / P]
In the present invention, simultaneous improvement of various properties is realized by controlling the size and amount of the Ni-P-based precipitates. Therefore, it is desirable to optimize the amount ratio of Ni and P added. According to the study by the inventors, the value of Ni / P represented by the ratio of the Ni amount to the P amount by mass% is preferably 2 to 30, and more preferably 5 to 25. If Ni / P becomes too large, the plating adhesion and solder weather resistance will be reduced, and the size of the precipitates will tend to increase, increasing the amount of precipitates of large particle size that contribute to press punchability. This tends to cause a decrease in bending workability and stress relaxation resistance. Furthermore, the amount of coarse precipitates also increases. Conversely, if Ni / P is too small, it is difficult to form a precipitate having a large particle size that contributes to press punchability. This tendency becomes remarkable when the amount of P is large. For this reason, when P content exceeds 0.1 mass%, it is desirable to add more Ni within the allowable range so that Ni / P is 5 or more.

〔Ｚｎ〕
Ｚｎは本発明の銅合金の機械特性および耐応力緩和特性を損なうことなくはんだ耐候性、めっき密着性等を向上させる作用を有するので、必要に応じてＺｎを含有させることができる。上記のような効果を十分に得るためには０.０５質量％以上のＺｎ含有が望まれる。Ｚｎ含有量を多めにすることにより原料コストが低減できるメリットがあるが、多量のＺｎ添加は導電性を低下させるだけでなく、応力腐食割れの感受性を高める要因になり、耐応力緩和特性も低下する。このためＺｎを含有させる場合はその含有量を５質量％以下とする必要があり、３質量％以下とすることがより好ましく、１質量％以下の範囲に規制することもできる。 [Zn]
Since Zn has an effect of improving solder weather resistance, plating adhesion, etc. without impairing the mechanical properties and stress relaxation resistance of the copper alloy of the present invention, Zn can be contained as required. In order to sufficiently obtain the above effects, 0.05% by mass or more of Zn is desired. There is a merit that raw material cost can be reduced by increasing the Zn content, but adding a large amount of Zn not only decreases the conductivity but also increases the susceptibility to stress corrosion cracking and also reduces the stress relaxation resistance. To do. For this reason, when it contains Zn, it is necessary to make the content into 5 mass% or less, it is more preferable to set it as 3 mass% or less, and it can also be controlled in the range of 1 mass% or less.

〔Ｍｎ、Ｃｏ〕
ＭｎおよびＣｏはＰと化合物を作り、Ｍｎ−Ｐ系、Ｃｏ−Ｐ系の析出物や、多元系のＭｎ−Ｎｉ−Ｐ系、Ｃｏ−Ｎｉ−Ｐ系の析出物を形成する。これらＭｎやＣｏを含む析出物はＮｉ−Ｐ系析出物よりも析出開始温度が高いので、ＭｎやＣｏの添加はプレス打抜き性の向上を担う粒径が大きいタイプの析出物の必要量を確保する上で有利となる。また、これらの析出物により耐熱性の向上を図ることも可能である。このため、必要に応じてＭｎまたはＣｏをＮｉに置換する形で含有させることができる。ただし、ＭｎやＣｏの含有量が多すぎると粒径が大きいタイプの析出物の量が多くなりすぎたり、粗大析出物の存在量が多くなりすぎたりするため、曲げ加工性、耐応力緩和特性およびめっきの表面性状が低下し好ましくない。このため、Ｍｎ、Ｃｏとも含有量は０.３質量％以下とすることが望ましい。Ｍｎ、Ｃｏは単独で含有させても複合して含有させても構わないが、Ｍｎ、Ｃｏとも０.０００５〜０.３質量％の範囲で含有させることが効果的であり、０.０１〜０.１質量％の範囲とすることが一層好ましい。ただし、原子％に換算した含有量において、ＭｎとＣｏの合計含有量がＮｉ含有量を超えないようにすることが肝要である。 [Mn, Co]
Mn and Co form a compound with P to form Mn—P and Co—P based precipitates and multi-element Mn—Ni—P and Co—Ni—P based precipitates. Since these precipitates containing Mn and Co have a higher precipitation start temperature than Ni-P-based precipitates, the addition of Mn and Co ensures the necessary amount of precipitates with a large particle size responsible for improving press punchability. This is advantageous. Moreover, it is also possible to improve heat resistance with these precipitates. For this reason, Mn or Co can be contained in the form of substituting Ni if necessary. However, if there is too much content of Mn or Co, the amount of precipitates with a large particle size will increase too much or the amount of coarse precipitates will increase too much, so bending workability and stress relaxation resistance In addition, the surface properties of the plating deteriorate, which is not preferable. For this reason, the content of both Mn and Co is desirably 0.3% by mass or less. Mn and Co may be contained alone or in combination, but it is effective to contain both Mn and Co in the range of 0.0005 to 0.3% by mass. It is still more preferable to set it as the range of 0.1 mass%. However, it is important that the total content of Mn and Co does not exceed the Ni content in the content converted to atomic%.

〔Ｆｅ〕
ＦｅはＰと化合物を作り、Ｎｉ−Ｐ系析出物より析出開始温度の高いＦｅ−Ｐ系、Ｆｅ−Ｎｉ−Ｐ系の析出物を形成する。このため前記ＭｎやＣｏと同様にプレス打抜き性の向上を担う粒径が大きいタイプの析出物の必要量を確保する上で有利となる。その作用を十分に発揮させるには０.０５質量％以上のＦｅ含有量を確保することがより効果的である。ただしＦｅ含有量が多すぎると前記ＭｎやＣｏと同様の弊害を生じる。また、Ｆｅは素材表面で酸化物を形成しやすく、めっき曇りを発生させやすい。このためＦｅを含有させる場合は０.３質量％以下の含有量とする必要があり、０.１質量％以下とすることがより好ましい。また、Ｎｉ／Ｆｅ比としては、Ｎｉ／Ｆｅ≧２であることが好ましく、Ｎｉ／Ｆｅ≧１０であることが更に好ましい。めっき性や表面の耐酸化性を特に重視する場合は、Ｆｅ含有量を０.００５質量％以下（分析による検出限界以下を含む）に制限するよう、組成調整することも有効である。 [Fe]
Fe forms a compound with P and forms Fe-P and Fe-Ni-P-based precipitates having a higher precipitation start temperature than Ni-P-based precipitates. For this reason, like Mn and Co, it is advantageous in securing the necessary amount of precipitates having a large particle size that is responsible for improving the press punchability. It is more effective to secure an Fe content of 0.05% by mass or more in order to fully exert its action. However, if the Fe content is too large, the same harmful effects as Mn and Co occur. Further, Fe tends to form an oxide on the surface of the material, and easily causes plating fogging. For this reason, when it contains Fe, it is necessary to set it as 0.3 mass% or less content, and it is more preferable to set it as 0.1 mass% or less. Further, the Ni / Fe ratio is preferably Ni / Fe ≧ 2, and more preferably Ni / Fe ≧ 10. When emphasis is placed on the plating property and surface oxidation resistance, it is also effective to adjust the composition so that the Fe content is limited to 0.005% by mass or less (including the detection limit or less by analysis).

〔Ｍｇ〕
Ｍｇはプレス打抜き性の向上および耐応力緩和特性の向上をもたらす元素である。Ｍｇによる耐応力緩和特性の向上効果を十分に得るには０.００５質量％以上のＭｇ含有が望まれる。ただし、Ｍｇ−Ｐ系析出物、Ｎｉ−Ｍｇ−Ｐ系析出物が生成すると、曲げ加工性が急激に低下する。またこの析出物は７００℃以下の温度域で生成するため、後述のように熱間圧延時に７００℃以下で１パス以上の圧下を行う場合などはこの析出物が熱間加工割れを招きやすく、ひいては冷間加工性を低下させる。それだけではなく曲げ加工性の急激な低下をも引き起こすので注意が必要である。このような理由で、Ｍｇを含有させる場合は０.１５質量％以下の含有量とする必要があり、０.０５質量％以下とすることがより好ましい。後述する不純物Ａｌ、Ｔｉ、Ｓｉの合計含有量が０.００１質量％を超えている場合は、これらの元素との相乗効果により曲げ加工性、製造性の低下が顕著になるため、Ｍｇ含有量は０.００１質量％以下に制限することが好ましい。 [Mg]
Mg is an element that provides improved press punchability and improved stress relaxation resistance. In order to sufficiently obtain the effect of improving the stress relaxation resistance by Mg, 0.005% by mass or more of Mg is desired. However, when the Mg—P based precipitate and the Ni—Mg—P based precipitate are generated, the bending workability is drastically lowered. In addition, since this precipitate is generated in a temperature range of 700 ° C. or less, as described later, when performing one-pass or more reduction at 700 ° C. or less during hot rolling, the precipitate is likely to cause hot working cracks, As a result, cold workability is reduced. Not only that, but it also causes a sharp decline in bending workability, so care must be taken. For these reasons, when Mg is contained, the content must be 0.15% by mass or less, and more preferably 0.05% by mass or less. When the total content of impurities Al, Ti, and Si, which will be described later, exceeds 0.001% by mass, a decrease in bending workability and manufacturability is remarkable due to a synergistic effect with these elements. Is preferably limited to 0.001% by mass or less.

〔Ａｌ、Ｔｉ、Ｓｉ〕
本発明は２種類のタイプの析出物が混在する組織状態を必要とするため、析出物の粗大化等、析出物の形態に悪影響を及ぼす元素はできるだけ排除することが望ましい。特にＡｌ、Ｔｉ、Ｓｉはスクラップから混入する可能性があり、極微量の混入で析出物の粗大化を助長する。また、曲げ加工性の低下、溶解・鋳造時の表面欠陥や内部欠陥の増大、接触抵抗の経時劣化速度の増大、はんだ耐候性の低下を招く。このようなことから、Ａｌ、Ｔｉ、Ｓｉの合計含有量は０.００１質量％以下に管理することが望ましく、特にこれらの元素の合計含有量が通常の銅合金製造現場での分析で検出されないレベルに管理することが一層好ましい。 [Al, Ti, Si]
Since the present invention requires a structure state in which two types of precipitates are mixed, it is desirable to eliminate as much as possible elements that adversely affect the form of precipitates, such as coarsening of precipitates. In particular, Al, Ti, and Si may be mixed from scrap, and an extremely small amount of mixed promotes the coarsening of precipitates. In addition, bending workability, surface defects and internal defects at the time of melting and casting, an increase in deterioration rate of contact resistance with time, and solder weatherability are reduced. For this reason, it is desirable to control the total content of Al, Ti, and Si to 0.001% by mass or less, and in particular, the total content of these elements is not detected by analysis at a normal copper alloy manufacturing site. It is more preferable to manage the level.

〔その他の不純物元素〕
Ｏ（酸素）は製造工程中での熱間圧延割れやフラックスの巻き込みといった欠陥の原因になりやすいので５０ｐｐｍ以下、好ましくは３０ｐｐｍ以下に抑えることが望ましい。Ｈ（水素）は膨れ等の欠陥の原因になりやすいので３ｐｐｍ以下、好ましくは２ｐｐｍ以下に抑えることが望ましい。Ｓは熱間加工割れの原因となりやすく、また曲げ加工性の低下を招きやすいので２０ｐｐｍ以下、好ましくは１０ｐｐｍ以下に抑えることが望ましい。 [Other impurity elements]
O (oxygen) is liable to cause defects such as hot rolling cracks and flux entrainment during the manufacturing process, so it is desirable to keep it at 50 ppm or less, preferably 30 ppm or less. Since H (hydrogen) tends to cause defects such as blistering, it is desirable to keep it at 3 ppm or less, preferably 2 ppm or less. Since S tends to cause hot working cracks and tends to cause a decrease in bending workability, it is desirable to suppress it to 20 ppm or less, preferably 10 ppm or less.

次に、本発明の銅合金材料の好適な製造方法について説明する。製造工程は、大きくは従来一般的なＣｕ−Ｎｉ−Ｓｎ−Ｐ系銅合金の製造工程で実施可能であるが、特に鋳造および熱間圧延工程に工夫を加えることが効果的である。代表的な製造工程は次のようなものである。
溶解・鋳造→熱間圧延→冷間圧延→焼鈍→冷間圧延→低温焼鈍 Next, the suitable manufacturing method of the copper alloy material of this invention is demonstrated. Although the production process can be carried out largely by a conventional production process of a Cu—Ni—Sn—P-based copper alloy, it is particularly effective to devise the casting and hot rolling processes. A typical manufacturing process is as follows.
Melting / Casting → Hot Rolling → Cold Rolling → Annealing → Cold Rolling → Low Temperature Annealing

途中の「冷間圧延→焼鈍」は必要に応じて複数回行うことができる。熱間圧延の後には一般的には面削が行われる。また、焼鈍後には適宜酸洗や研磨が行われ、必要に応じて脱脂が行われる。
前述した２種類のタイプの析出物のうち、プレス打抜き性の改善に寄与する粒径の大きいタイプの析出物は主として熱間圧延工程で生成させる。強度や耐応力緩和特性の向上に寄与する微細なタイプの析出物は熱間圧延後に行われる何回かの焼鈍工程の少なくとも１つ以上において時効処理を兼ねることで析出させる。 The “cold rolling → annealing” in the middle can be performed a plurality of times as necessary. In general, chamfering is performed after hot rolling. Further, after annealing, pickling and polishing are appropriately performed, and degreasing is performed as necessary.
Of the two types of precipitates described above, the type of precipitate having a large particle size that contributes to the improvement of press punchability is produced mainly in the hot rolling process. Fine type precipitates that contribute to the improvement of strength and stress relaxation resistance are precipitated by serving as an aging treatment in at least one of several annealing steps performed after hot rolling.

〔溶解・鋳造〕
上で規定した組成の合金を溶解して、鋳造する。基本的に大気中での溶解・鋳造が可能であるが、溶湯の酸化、水素の浸入を防ぐため、湯面を黒鉛やフラックス等の被覆材で被覆することが望ましい。鋳造に際しては凝固時の偏析により過度に粗大な析出物が生成することを防止するため、凝固後の冷却過程では７００〜４００℃の間の平均冷却速度を３０℃／ｍｉｎ以上とすることが重要である。６０℃／ｍｉｎ以上とすることが一層好ましい。このような冷却速度は、連続鋳造法においては鋳片の強制冷却（水冷等）によって実現できる。バッチ式の鋳造では凝固完了後のインゴット（鋳塊）を７００℃に到達するまでに鋳型ごとあるいは鋳型から取り出して水中に没する方法などによって実現できる他、インゴットが扁平形状の場合には鋳型の強制冷却によっても実現可能である。 [Melting / Casting]
An alloy having the composition defined above is melted and cast. Basically, melting and casting in the atmosphere is possible, but it is desirable to coat the molten metal surface with a coating material such as graphite or flux in order to prevent oxidation of the molten metal and intrusion of hydrogen. In casting, in order to prevent the formation of excessively coarse precipitates due to segregation during solidification, it is important that the average cooling rate between 700 and 400 ° C. is 30 ° C./min or more in the cooling process after solidification. It is. More preferably, it is 60 ° C./min or more. Such a cooling rate can be realized by forced cooling (water cooling or the like) of the slab in the continuous casting method. In batch type casting, the ingot (ingot) after completion of solidification can be realized by a method such as removing the mold or removing it from the mold and immersing it in water before reaching 700 ° C. If the ingot is flat, It can also be realized by forced cooling.

〔熱間圧延〕
得られた鋳片またはインゴットを８５０〜９６０℃の炉中に装入し、材料全体が７００℃以上になってから２時間以上とし、望ましくは３時間以上とするのが良い。また、８００℃以上になってからの保持時間は１時間以上とし、好ましくは２時間以上とすることが望ましい。これにより鋳片またはインゴットの均質化と鋳造時に生じた析出物の再固溶を行う。その後炉から抽出して熱間圧延を行う。その際、材料温度が７００〜４００℃にある時間（圧下を行っている時間を含む）を２０ｓｅｃ〜３０ｍｉｎの範囲で確保することが重要である。この処理によりプレス打抜き性の向上に寄与する粒径の大きいタイプの析出物を前記所定の密度で生成させることができるのである。材料温度が７００〜４００℃にある時間が短すぎると粒径の大きいタイプの析出物を十分形成させることができない。また、あまり長時間では粗大化が進み、上述した所望の析出形態が実現できない。材料温度が７００〜４００℃にある時間は１〜１５ｍｉｎとすることがより好ましく、３〜１０ｍｉｎとすることが一層好ましい。また特に、材料温度が７００〜５００℃にある時間を２０ｓｅｃ〜３０ｍｉｎとするような管理がより好ましく、その時間を１〜１５ｍｉｎとすること、あるいはさらに３〜１０ｍｉｎとすることが特に好ましい。 (Hot rolling)
The resulting slab or ingot was placed in a furnace of 8 50 to 960 ° C., and after becoming the entire material 7 00 ° C. or more and 2 hours or more, and desirably between the three or more hours. The holding time from the above 800 ° C. is not less than 1 hour, it is desirable to preferably be at least 2 hours. This homogenizes the slab or ingot and re-dissolves the precipitates produced during casting. Then, it is extracted from the furnace and hot rolled. At that time, it is important to ensure the time during which the material temperature is 700 to 400 ° C. (including the time during which the reduction is performed) in the range of 20 sec to 30 min. By this treatment, a precipitate having a large particle size that contributes to the improvement of press punchability can be generated at the predetermined density. If the material temperature is 700 to 400 ° C. for a too short time, a precipitate having a large particle size cannot be sufficiently formed. In addition, if the time is too long, the coarsening progresses, and the desired precipitation form described above cannot be realized. The time during which the material temperature is 700 to 400 ° C. is more preferably 1 to 15 minutes, and further preferably 3 to 10 minutes. In particular, management such that the time during which the material temperature is 700 to 500 ° C. is set to 20 sec to 30 min is more preferable, and the time is preferably set to 1 to 15 min, or more preferably 3 to 10 min.

また、７００℃以下の温度域で１パス以上の圧下を行う。この１パス以上の圧下により粒径の大きいタイプの析出物が導入されやすくなる。そのためには例えば最終パス温度（仕上温度）を７００〜４００℃の範囲に設定すればよい。熱間圧延後の板厚は概ね８〜２０ｍｍの範囲で設定することができる。板厚が薄く温度降下が速い場合は、保温設備のある圧延機を使用することも効果的である。最終パス終了後、材料温度が７００〜４００℃好ましくは７００〜５００℃にある時間を上記所定の範囲で確保した後は、水冷することが望ましい。 Further, it intends rows pressure of more than one pass in a temperature range of 700 ° C. or less. This pressure reduction of one pass or more facilitates the introduction of a large particle size type precipitate. For this purpose, for example, the final pass temperature (finishing temperature) may be set in the range of 700 to 400 ° C. The plate thickness after hot rolling can be set in a range of approximately 8 to 20 mm. When the plate thickness is thin and the temperature drop is fast, it is also effective to use a rolling mill with heat insulation equipment. After the final pass, the material temperature is preferably 700 to 400 ° C., preferably 700 to 500 ° C., after securing the time within the above predetermined range, it is desirable to cool with water.

〔冷間圧延、焼鈍〕
熱間圧延後は面削などによって表面のスケールを取り除いたのち、冷間圧延と焼鈍の工程に供する。最終的な目標板厚に応じて、冷間圧延と焼鈍を１回または２回以上行う。その際、１回の冷間圧延率は、中間圧延の場合は概ね４５〜９５％、仕上圧延の場合は概ね２５〜８０％の範囲とすればよい。 [Cold rolling, annealing]
After hot rolling, the surface scale is removed by chamfering or the like, and then subjected to cold rolling and annealing processes. Depending on the final target thickness, cold rolling and annealing are performed once or twice or more. At that time, the cold rolling rate per time may be approximately 45 to 95% in the case of intermediate rolling and approximately 25 to 80% in the case of finish rolling.

焼鈍では時効処理を兼ねるようにして、強度や耐応力緩和特性の向上に寄与する微細なタイプの析出物を生成させる。
時効処理を兼ねた焼鈍の条件として以下のものが採用できる。
・バッチ式焼鈍の場合： ３５０〜６５０℃で０.５〜２０ｈ保持する。４００〜６００℃で１〜８ｈ保持することがより望ましい。
・連続焼鈍の場合： 板厚、炉長により異なるが、通常４００〜８５０℃×３ｓｅｃ〜１５ｍｉｎ保持の範囲で良好な条件が設定できる。５００〜７５０℃で３ｓｅｃ〜５ｍｉｎ保持することがより望ましい。
連続焼鈍では、その熱処理条件の選択により、昇温過程中に析出を生じさせ、かつ再固溶させずに析出物を残存させることができる。微細なタイプの析出物の析出量はバッチ式よりも一般的に少なくなるが、強度、導電性、耐応力緩和特性等の基本特性は十分維持できる。 Annealing also serves as an aging treatment to produce fine types of precipitates that contribute to the improvement of strength and stress relaxation resistance.
The following conditions can be adopted as annealing conditions that also serve as an aging treatment.
-In the case of batch-type annealing: Hold at 350 to 650 ° C for 0.5 to 20 hours. It is more desirable to hold at 400 to 600 ° C. for 1 to 8 hours.
In the case of continuous annealing: Although it varies depending on the plate thickness and furnace length, favorable conditions can be set in the range of usually 400 to 850 ° C. × 3 sec to 15 min. It is more desirable to hold at 500 to 750 ° C. for 3 sec to 5 min.
In the continuous annealing, by selecting the heat treatment conditions, precipitation can occur during the temperature rising process, and the precipitate can remain without being re-dissolved. Although the precipitation amount of fine type precipitates is generally smaller than that of the batch type, basic properties such as strength, conductivity and stress relaxation resistance can be sufficiently maintained.

冷間圧延→焼鈍を複数回行う場合は、少なくとも１つ以上の焼鈍工程において時効処理を兼ねるようにする。その際、時効処理の合計時間が上記の所定範囲となるようにすればよい。
最終的には歪取りを兼ねた低温焼鈍を実施することが望ましい。その条件としては例えば連続炉で３００〜７５０℃で３〜２４０ｓｅｃ保持する条件が採用できる。 When performing cold rolling → annealing a plurality of times, the aging treatment is also performed in at least one or more annealing steps. At that time, the total time of the aging treatment may be set within the predetermined range.
Ultimately, it is desirable to perform low-temperature annealing that also serves as a strain relief. As the condition, for example, a condition of holding at 300 to 750 ° C. for 3 to 240 seconds in a continuous furnace can be adopted.

以上の方法が最も効率的な本発明の製造方法と考えられるが、本発明の析出物サイズの構成が得られる方法であれば、他の方法、例えば鋳造時に粗大な析出物を生成させ、焼鈍工程で一部を再固溶させることによりサイズの制御を行なう方法や、途中工程の焼鈍の温度、保持時間、冷却速度や昇温速度を工夫することにより本発明の析出物サイズを得る方法を採用することができる。   The above method is considered to be the most efficient production method of the present invention. However, as long as the composition of the precipitate size of the present invention is obtained, other methods, for example, coarse precipitates are generated during casting, and annealing is performed. A method of controlling the size by re-dissolving a part in the process and a method of obtaining the precipitate size of the present invention by devising the annealing temperature, holding time, cooling rate and heating rate of the intermediate process. Can be adopted.

本発明の銅合金は、端子、コネクタ、ソケット、バスバー等多種の電気電子部品に利用できるが、コネクタや等のばね性を要求される部品では、引張強さ５００Ｎ／ｍｍ²以上、且つ導電率３５％ＩＡＣＳ以上であることが好ましい。引張強さ５５０Ｎ／ｍｍ²以上、且つ導電率４０％ＩＡＣＳ以上であることが一層好ましい。
また、自動車のＪＢ用バスバーのような、導電率を重視する部品では、引張強さ４５０Ｎ／ｍｍ²以上、且つ導電率５５％ＩＡＣＳ以上であることが望ましい。 The copper alloy of the present invention can be used for various electrical and electronic parts such as terminals, connectors, sockets, bus bars, etc., but for parts that require springiness, such as connectors, the tensile strength is 500 N / mm ² or more, and the electrical conductivity. It is preferably 35% IACS or more. More preferably, the tensile strength is 550 N / mm ² or more and the conductivity is 40% IACS or more.
In addition, it is desirable that a component such as an automobile JB bus bar that emphasizes electrical conductivity has a tensile strength of 450 N / mm ² or more and an electrical conductivity of 55% IACS or more.

表１に示す組成の銅合金板材を以下の工程Ａ〜Ｄいずれかの製造工程で製造した。工程Ａが本発明の対象となる製造工程、それ以外が本発明の適正条件を外れる製造工程である。   A copper alloy sheet having the composition shown in Table 1 was produced by any one of the following production steps A to D. Process A is a manufacturing process that is an object of the present invention, and other processes are manufacturing processes that deviate from the proper conditions of the present invention.

〔工程Ａ〕
断面形状約２００×５００ｍｍ、長さ約３５００ｍｍの鋳片を半連続鋳造により製造した。その際、雰囲気は大気とし、湯面を木炭を主体とする被覆材で被覆した。鋳片は凝固部分を約３００℃以下の温度域まで水冷することにより、７００〜４００℃の平均冷却速度が６０℃／ｍｉｍ以上になるようにした。
得られた鋳片を大気雰囲気、９００〜９４０℃の炉に装入し、約４ｈ保持した。その後抽出し、板厚１０ｍｍまで熱間圧延した。最終パス温度は概ね６５０℃前後である。材料温度が７００℃以下になっいる時間が圧下を行っている時間を含めて３〜１０ｍｉｎの範囲に収まるようにコントロールした。そして約６００℃から水冷を開始して１５０℃以下の温度域まで急冷した。 [Process A]
A slab having a cross-sectional shape of about 200 × 500 mm and a length of about 3500 mm was manufactured by semi-continuous casting. At that time, the atmosphere was air, and the hot water surface was covered with a covering material mainly composed of charcoal. The slab was water-cooled to a temperature range of about 300 ° C. or lower so that the average cooling rate of 700 to 400 ° C. was 60 ° C./mim or more.
The obtained slab was charged into a furnace at 900 to 940 ° C. in an air atmosphere and held for about 4 hours. Then, it extracted and hot-rolled to plate thickness 10mm. The final pass temperature is approximately around 650 ° C. The time when the material temperature was 700 ° C. or lower was controlled so as to be within the range of 3 to 10 min including the time during which the material was being reduced. And water cooling was started from about 600 degreeC, and it rapidly cooled to the temperature range below 150 degreeC.

熱間圧延された板は面削したのち、厚さ１.８ｍｍまで冷間圧延した。その後、バッチ式の熱処理炉を用いて時効処理を兼ねた焼鈍を行った。焼鈍条件は５５０℃×４ｈである。
次いで、酸洗、研磨を行った後、厚さ０.６４ｍｍまで仕上冷間圧延を行った。その後、歪取りを主目的とする低温焼鈍を連続炉で行った。低温焼鈍条件は５００℃の炉中での短時間の熱処理とし、低温焼鈍前の状態から引張強さが１５〜３０Ｎ／ｍｍ²低下する条件（時間にして５〜２５ｓｅｃの範囲内）とした。
最終的に酸洗、研磨を行って板厚０.６４ｍｍとし、これを供試材とした。 The hot-rolled plate was chamfered and then cold-rolled to a thickness of 1.8 mm. Then, annealing which served as aging treatment was performed using a batch type heat treatment furnace. The annealing condition is 550 ° C. × 4 h.
Next, after pickling and polishing, finish cold rolling was performed to a thickness of 0.64 mm. After that, low temperature annealing mainly for strain relief was performed in a continuous furnace. The low-temperature annealing condition was a short-time heat treatment in a furnace at 500 ° C., and the tensile strength was reduced by 15 to 30 N / mm ² from the state before the low-temperature annealing (within a time range of 5 to 25 sec).
Finally, pickling and polishing were performed to obtain a plate thickness of 0.64 mm, which was used as a test material.

〔工程Ｂ〕
工程Ａにおいて、熱間圧延工程で材料温度が７００〜４００℃にある時間が約１ｈとなるように４００℃まで保温装置を利用して徐冷し、その後水冷した。それ以外は工程Ａと共通である。
〔工程Ｃ〕
工程Ａにおいて、７５０℃で最終パスを終了させ、その後直ちに水冷した。それ以外は工程Ａと共通である。
〔工程Ｄ〕
工程Ａにおいて、鋳造時に鋳片の冷却速度を変えて、鋳込み後、鋳片温度が４００℃になるまでの時間を約２ｈとした。それ以外は工程Ａと共通である。 [Process B]
In Step A, the material temperature was gradually cooled to 400 ° C. using a heat retaining device so that the time during which the material temperature was 700 to 400 ° C. in the hot rolling step was about 1 h, and then water-cooled. The rest is the same as the process A.
[Process C]
In Step A, the final pass was completed at 750 ° C., and then immediately cooled with water. The rest is the same as the process A.
[Process D]
In step A, the cooling rate of the slab was changed during casting, and the time until the slab temperature reached 400 ° C. after casting was about 2 h. The rest is the same as the process A.

各供試材からサンプルを採取して、透過型電子顕微鏡（日本電子株式会社製、ＪＥＭ−２０１０）により以下のようにして析出物の数を調べた。
加速電圧２００ｋＶ、倍率５００００倍にて、任意の３箇所の視野を選んで、フォーカスを固定した状態で観察される析出物を対象として、粒径が２０〜１５０ｎｍの範囲にあるもの、および粒径が１５０ｎｍを超えるものの個数をカウントした。対象となる粒子のうち、粒径が上記いずれかの範囲にあるかどうかが明らかでない粒子については、倍率を上げて観察することにより正確を期した。観察領域の合計面積は各供試材とも３.０×１０⁶〜４.８×１０⁶ｎｍ²程度であり、カウントされた析出物の個数に「単位面積／観察領域の合計面積」の値を乗じることにより、単位面積（１.５×１０⁶ｎｍ²）あたりの析出物の密度を算出した。粒径が２０ｎｍ未満の微細な析出物については、いずれの供試材にも単位面積（１.５×１０⁶ｎｍ²）あたり１００個以上存在していることが確かめられた。それらはほとんどが粒径１０ｎｍ以下のものであった。
析出物の密度を表１に示す。
なお、いずれの合金も分析の結果Ｏ：３０ｐｐｍ以下、Ｈ：２ｐｐｍ以下、Ｓ：１０ｐｐｍ以下であった。 Samples were collected from each test material, and the number of precipitates was examined by a transmission electron microscope (JEM-2010, manufactured by JEOL Ltd.) as follows.
A particle having a particle size in the range of 20 to 150 nm for a precipitate observed with a fixed focus when an arbitrary three visual fields are selected at an acceleration voltage of 200 kV and a magnification of 50000 times, and a particle size Were counted over 150 nm. Among the target particles, for those particles whose particle size is not clear in any of the above ranges, the accuracy was increased by observing at a higher magnification. The total area of the observation region is about 3.0 × 10 ^{6 to} 4.8 × 10 ⁶ nm ^{2 for} each specimen, and the value of “unit area / total area of the observation region” is added to the number of precipitates counted. The density of precipitates per unit area (1.5 × 10 ⁶ nm ² ) was calculated. As for fine precipitates having a particle size of less than 20 nm, it was confirmed that 100 or more particles per unit area (1.5 × 10 ⁶ nm ² ) existed in any of the test materials. Most of them had a particle size of 10 nm or less.
Table 1 shows the density of the precipitates.
As a result of analysis, all alloys were O: 30 ppm or less, H: 2 ppm or less, and S: 10 ppm or less.

各供試材について以下の特性を調べた。
〔引張強さ、０.２％耐力〕
ＪＩＳ ５号引張試験片を用いてＪＩＳ Ｚ２２４１に従って圧延方向に対し平行方向の引張試験を行って求めた。
〔導電率〕
ＪＩＳ Ｈ０５０５に従って求めた。 The following characteristics were examined for each specimen.
[Tensile strength, 0.2% yield strength]
Using a JIS No. 5 tensile test piece, the tensile test was performed in a direction parallel to the rolling direction in accordance with JIS Z2241.
〔conductivity〕
It calculated | required according to JISH0505.

〔応力緩和率〕
日本電子材料工業会標準規格ＥＭＡＳ−１０１１（平成３年１２月）に準拠した方法で、以下のようにして求めた。すなわち、供試材から幅１０ｍｍ、長さ１５０ｍｍの試験片（その長手方向が圧延方向に相当）を切り出し、試験片中央部の表面応力（表面最大応力）が０.２％耐力の８０％となるようにアーチ曲げした状態で固定し、大気中１５０℃で１０００時間保持した後の曲げ癖を応力緩和率として次式により算出した。
応力緩和率（％）＝（ｈ₁／ｈ₀）×１００
ただし、ｈ₁：試験経過後の応力除荷時における試験片の永久たわみ変位（ｍｍ）
ｈ₀：上記応力を得るのに必要な試験片の初期たわみ変位（ｍｍ）
この試験方法において応力緩和率が１０％以下のものは、特に優れた耐応力緩和特性を有すると判断される。 [Stress relaxation rate]
It calculated | required as follows by the method based on Japan Electronics Material Industries Association standard EMAS-1011 (December, 1991). That is, a specimen having a width of 10 mm and a length of 150 mm was cut out from the specimen (the longitudinal direction corresponds to the rolling direction), and the surface stress (maximum surface stress) at the center of the specimen was 0.2% and 80% of the proof stress. The bending wrinkle after being fixed in an arch-bent state and held at 150 ° C. for 1000 hours in the atmosphere was calculated as the stress relaxation rate by the following equation.
Stress relaxation rate (%) = (h ₁ / h ₀ ) × 100
However, h ₁ : Permanent deflection displacement (mm) of the test piece at the time of stress unloading after the test
h ₀ : Initial deflection displacement (mm) of the test piece necessary for obtaining the stress
In this test method, those having a stress relaxation rate of 10% or less are judged to have particularly excellent stress relaxation resistance.

〔曲げ加工性〕
曲げ軸が圧延方向に対し平行方向（ＢＷ）の９０°曲げ試験（ＪＩＳ Ｈ３１１０に準拠、Ｒ＝０.６ｍｍ、幅Ｗ＝１０ｍｍ）を実施し、曲げ部の曲げ軸に垂直な断面を光学顕微鏡にて１００倍の倍率で観察し、割れが認められないものを○（良好）、認められものを×（不良）と判定した。 [Bending workability]
A 90 ° bending test (based on JIS H3110, R = 0.6 mm, width W = 10 mm) in which the bending axis is parallel to the rolling direction (BW) was performed, and a cross section perpendicular to the bending axis of the bending portion was subjected to an optical microscope The sample was observed at a magnification of 100 times, and the case where no crack was observed was judged as ◯ (good), and the case where crack was found was judged as x (bad).

〔プレス打抜き性〕
プレス打抜き性の試験は、ＪＣＢＡ Ｔ３１０：２００２に準拠して行なった。パンチ径１０.００ｍｍ、ダイの打抜き穴径１０.１０ｍｍの丸型パンチを用いて、約８％のクリアランスでプレスの打抜き試験を行った。プレス条件として、プレス速度１ｍｍ／ｍｉｎ、潤滑油無しとして、各供試材につき１０回行った。
直径１０ｍｍの穴が打ち抜かれて残った材料について、打抜き面に垂直かつ板厚方向に平行な断面を光学顕微鏡で観察することにより「えぐれ深さ」および「ダレ率」を測定した。その観察試験片は、圧延方向に平行な断面を４箇所、および圧延方向に垂直な断面を４箇所それぞれ任意に選んで、計８箇所について測定した。図１に試験片の断面形状を模式的に示す。Ｔは板厚、ａはダレ量、ｂはえぐれ深さである。ダレ率の値はａ／Ｔで表される。８個の観察試料の測定結果に基づき、以下のように評価した。
・えぐれ深さ： ８個の観察試料のうち、ｂ／Ｔ比が７％を超える試料が１つもない材料を○（良好）、１つ以上ある材料を×（不良）と判定した。
・ダレ率： ８個の観察試料のダレ率ａ／Ｔの平均値（以下「平均ダレ率」という）を算出し、平均ダレ率が９％以下の材料を○（良好）、９％を超える材料を×（不良）と判定した。 [Press punchability]
The press punchability test was performed according to JCBA T310: 2002. Using a round punch having a punch diameter of 10.00 mm and a die punching hole diameter of 10.10 mm, a punching test of the press was performed with a clearance of about 8%. As the pressing conditions, the pressing speed was 1 mm / min and no lubricating oil was used, and each test material was performed 10 times.
With respect to the material left by punching a hole having a diameter of 10 mm, the “depth of penetration” and the “sag rate” were measured by observing a cross section perpendicular to the punched surface and parallel to the thickness direction with an optical microscope. The observation test pieces were measured at a total of 8 locations by arbitrarily selecting 4 cross sections parallel to the rolling direction and 4 cross sections perpendicular to the rolling direction. FIG. 1 schematically shows the cross-sectional shape of the test piece. T is the plate thickness, a is the sagging amount, and b is the depth of penetration. The value of the sag rate is represented by a / T. Based on the measurement results of the eight observation samples, evaluation was performed as follows.
Depth of Depth: Out of 8 observation samples, a material having no sample having a b / T ratio exceeding 7% was judged as ◯ (good), and one or more materials were judged as x (bad).
Sagging rate: The average value of the sagging rate a / T of 8 observation samples (hereinafter referred to as “average sagging rate”) is calculated. A material having an average sagging rate of 9% or less is ◯ (good) and exceeds 9%. The material was judged as x (defect).

〔はんだ耐候性〕
はんだ耐候性については、各サンプルを脱脂した後、弱活性フラックスを用いてはんだ付けを行なった。使用したはんだはＰｂ−４０Ｓｎの共晶はんだで、２３５℃ではんだ付けを行なった後、１５０℃のオーブンで１０００ｈｒ加熱した後、Ｒ＝１.２の９０°Ｗ曲げ試験を行い、曲げ部外側の表面についてＪＩＳ Ｚ１５２２に規定のセロハン粘着テープを用いた剥離試験を行った。
上記試験ではんだ層の剥離が認められなかったものを○（良好）、剥離が認められたものを×（不良）と判定した。
結果を表２に示す。 [Solder weather resistance]
About solder weather resistance, after degreasing each sample, it soldered using weakly active flux. The solder used was a Pb-40Sn eutectic solder, soldered at 235 ° C, heated in an oven at 150 ° C for 1000 hours, and then subjected to a 90 ° W bending test with R = 1.2. A peel test using the cellophane adhesive tape defined in JIS Z1522 was conducted on the surface of
In the above test, the case where peeling of the solder layer was not recognized was judged as ◯ (good), and the case where peeling was recognized was judged as x (defective).
The results are shown in Table 2.

表２からわかるように、本発明例のものは粒径２０〜１５０ｎｍの析出物の密度が１.５×１０⁶ｎｍ²あたり０.３〜３０個を満たし、かつ粒径１５０ｎｍを超える粗大析出物は存在しないか、存在しても１.５×１０⁶ｎｍ²あたり３個以下を満たしていた。その結果、強度（引張強さ、０.２％耐力）、導電性、耐応力緩和特性、曲げ加工性、はんだ耐候性に優れるとともに、プレス打抜き性にも優れていた。 As can be seen from Table 2, in the examples of the present invention, the density of precipitates having a particle size of 20 to 150 nm satisfies 0.3 to 30 per 1.5 × 10 ⁶ nm ² and coarse precipitates having a particle size exceeding 150 nm. No object was present, or even when it was present, the number was 3 or less per 1.5 × 10 ⁶ nm ² . As a result, it was excellent in strength (tensile strength, 0.2% proof stress), conductivity, stress relaxation resistance, bending workability, solder weather resistance, and press punchability.

これに対し、比較例であるＹ１はＰ含有量が少なくＮｉ／Ｐが過大であったため粒径２０〜１５０ｎｍの析出物が形成できず、プレス打抜き性が向上しなかった。耐応力緩和特性にも劣った。Ｙ２はＰ含有量が多すぎたため、またＹ３はＮｉ含有量が多すぎたため、いずれも粒径２０〜１５０ｎｍの析出物および粒径１５０ｎｍを超える粗大析出物が多くなり、曲げ加工性、はんだ耐候性に劣った。Ｙ４はＳｎ含有量が少なすぎたことにより強度、耐応力緩和特性、曲げ加工性、はんだ耐候性に劣った。Ｙ５は熱間圧延時に７００〜４００℃にある時間が長すぎたことにより粒径２０〜１５０ｎｍの析出物が多量に生成し、強度、耐応力緩和特性、曲げ加工性に劣った。Ｙ６は熱間圧延時に７００℃以下の温度域にある時間を確保しなかったことにより粒径２０〜１５０ｎｍの析出物が形成できず、プレス打抜き性が改善できなかった。Ｙ７は鋳造時に７００〜４００℃の冷却速度が小さかったことにより粒径２０〜１５０ｎｍの析出物および粒径１５０ｎｍを超える粗大析出物が多くなり、曲げ加工性に劣った。Ｙ８はＮｉ含有量が少なかったため、耐応力緩和特性に劣り、えぐれ深さやはんだ耐候性も悪かった。Ｙ９はＭｇ含有量が多すぎ、Ｙ１１はＳｉを多く含むことにより、いずれも熱間圧延時に割れが発生し、その後の実験を断念した。Ｙ１０はＴｉ含有量が多く、また熱間圧延時に７００〜４００℃にある時間が長すぎたことにより粒径２０〜１５０ｎｍの析出物および粒径１５０ｎｍを超える粗大析出物が多量に生成し、曲げ加工性に劣り、更にはんだ耐候性に劣った。Ｙ１２はＦｅ含有量とＡｌ含有量が多いことにより粒径２０〜１５０ｎｍの析出物および粒径１５０ｎｍを超える粗大析出物が多量に生成し、耐応力緩和特性、曲げ加工性に劣り、えぐれ深さ、はんだ耐候性も悪かった。 On the other hand, Y1, which is a comparative example, had a low P content and an excessive Ni / P, so a precipitate having a particle size of 20 to 150 nm could not be formed, and the press punchability was not improved. It was also inferior in stress relaxation resistance. Since Y2 has too much P content and Y3 has too much Ni content, both of precipitates having a particle size of 20 to 150 nm and coarse precipitates having a particle size exceeding 150 nm are increased, bending workability and solder weather resistance. Inferior. Y4 was inferior in strength, stress relaxation resistance, bending workability, and solder weather resistance due to too little Sn content. Y5 produced a large amount of precipitates having a particle size of 20 to 150 nm because the time at 700 to 400 ° C. was too long during hot rolling, and was inferior in strength, stress relaxation resistance and bending workability. Y6 can not form precipitates having a particle size of 20~150nm by did not allow time in the temperature range of 700 ° C. or less during hot rolling, could not improve the press-punching properties. Y7 had a low cooling rate of 700 to 400 ° C. at the time of casting, so that precipitates having a particle size of 20 to 150 nm and coarse precipitates exceeding a particle size of 150 nm increased, and the bending workability was poor. Since Y8 had a small Ni content, Y8 was inferior in stress relaxation resistance, and the depth of penetration and solder weather resistance were also poor. Since Y9 has too much Mg content and Y11 contains a large amount of Si, cracks occurred during hot rolling, and the subsequent experiment was abandoned. Y10 has a large Ti content, and because the time at 700 to 400 ° C. during hot rolling is too long, precipitates with a particle size of 20 to 150 nm and coarse precipitates with a particle size exceeding 150 nm are produced in a large amount. It was inferior in workability and further inferior in solder weather resistance. Y12 produces a large amount of precipitates with a particle size of 20 to 150 nm and coarse precipitates with a particle size of more than 150 nm due to high Fe content and Al content, and is inferior in stress relaxation resistance and bending workability, and has a depth of penetration. The solder weather resistance was also poor.

プレス打抜き部分の断面形状を模式的に示した図。The figure which showed typically the cross-sectional shape of the press punching part.

Claims (4)

質量％でＮｉ：０.１５〜１.５％、Ｓｎ：０.１〜２.３％、Ｐ：０.０２〜０.２％、残部がＣｕおよび不可避的不純物からなる組成を有し、粒径２０ｎｍ未満の微細析出物が存在するとともに粒径２０〜１５０ｎｍの析出物が１.５×１０⁶ｎｍ²あたり０.３〜３０個の密度で存在し、粒径１５０ｎｍを超える粗大析出物が存在しないか、または１.５×１０ ⁶ ｎｍ ² あたり３個以下の密度で存在する組織を有するプレス打抜き性に優れた銅合金。 Ni: 0.15 to 1.5% by mass, Sn: 0.1 to 2.3%, P: 0.02 to 0.2%, the balance being composed of Cu and inevitable impurities , There are fine precipitates having a particle size of less than 20 nm, precipitates having a particle size of 20 to 150 nm are present at a density of 0.3 to 30 per 1.5 × 10 ⁶ nm ² , and coarse precipitates having a particle size exceeding 150 nm. Is a copper alloy excellent in press punching having no microstructure or a structure having a density of 3 or less per 1.5 × 10 ⁶ nm ² . 質量％でＮｉ：０.１５〜１.５％、Ｓｎ：０.１〜２.３％、Ｐ：０.０２〜０.２％を含み、さらにＺｎ：５％以下、Ｃｏ：０.３％以下、Ｍｎ：０.３％以下、Ｆｅ：０.３％以下およびＭｇ：０.１５％以下のうち１種または２種以上を含み、残部がＣｕおよび不可避的不純物からなる組成を有し、粒径２０ｎｍ未満の微細析出物が存在するとともに粒径２０〜１５０ｎｍの析出物が１.５×１０⁶ｎｍ²あたり０.３〜３０個の密度で存在し、粒径１５０ｎｍを超える粗大析出物が存在しないか、または１.５×１０ ⁶ ｎｍ ² あたり３個以下の密度で存在する組織を有するプレス打抜き性に優れた銅合金。 Ni: 0.15 to 1.5% by mass, Sn: 0.1 to 2.3%, P: 0.02 to 0.2%, Zn: 5% or less, Co: 0.3 % Or less, Mn: 0.3% or less, Fe: 0.3% or less, and Mg: 0.15% or less, and the balance is composed of Cu and inevitable impurities. In addition, fine precipitates having a particle size of less than 20 nm are present, and precipitates having a particle size of 20 to 150 nm are present at a density of 0.3 to 30 per 1.5 × 10 ⁶ nm ² , and coarse precipitates having a particle size exceeding 150 nm A copper alloy excellent in press punching having no structure or a structure having a density of 3 or less per 1.5 × 10 ⁶ nm ² . Ａｌ、Ｔｉ、Ｓｉの合計含有量０.００１質量％以下である請求項１または２に記載のプレス打抜き性に優れた銅合金。 Al, Ti, press-punching properties in excellent copper alloy according to claim 1 or 2 which is a total content 0.001 wt% or less of Si. 鋳造、熱間圧延、および１回以上の「冷間圧延、焼鈍」を含む製造工程において、鋳造時に７００〜４００℃の平均冷却速度を３０℃／ｍｉｎ以上とし、熱間圧延時に材料を８５０〜９６０℃の炉中に装入し、材料全体が７００℃以上になってから２時間以上、８００℃以上になってから１時間以上保持したのち炉から抽出して熱間圧延を行い、材料温度が７００〜４００℃にある時間を２０ｓｅｃ〜３０ｍｉｎの範囲で確保するとともに７００℃以下の温度域で１パス以上の圧下を行う、請求項１〜３のいずれかに記載のプレス打抜き性に優れた銅合金の製造法。 In a manufacturing process including casting, hot rolling, and one or more “cold rolling, annealing”, an average cooling rate of 700 to 400 ° C. is set to 30 ° C./min or more at the time of casting, and a material is set to 850 to 350 at the time of hot rolling. The material was charged in a furnace at 960 ° C., held for 2 hours or more after the whole material became 700 ° C. or more, held for 1 hour or more after 800 ° C. or more, extracted from the furnace and hot-rolled, and the material temperature Is excellent in press punchability according to any one of claims 1 to 3 , wherein a time of 700 to 400 ° C is ensured in a range of 20 sec to 30 min and reduction of one pass or more is performed in a temperature range of 700 ° C or less . Copper alloy manufacturing method.

Images