WO2021203629A1 - 一种综合性能优异的铜合金带材及其制备方法 - Google Patents

一种综合性能优异的铜合金带材及其制备方法 Download PDF

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Publication number
WO2021203629A1
WO2021203629A1 PCT/CN2020/116375 CN2020116375W WO2021203629A1 WO 2021203629 A1 WO2021203629 A1 WO 2021203629A1 CN 2020116375 W CN2020116375 W CN 2020116375W WO 2021203629 A1 WO2021203629 A1 WO 2021203629A1
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Prior art keywords
copper alloy
texture
alloy strip
rolling
strip
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PCT/CN2020/116375
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English (en)
French (fr)
Inventor
潘志军
吕文跃
侯汉卿
熊尚武
胡仁昌
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宁波博威合金板带有限公司
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Publication of WO2021203629A1 publication Critical patent/WO2021203629A1/zh

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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C9/00—Alloys based on copper
    • C22C9/06—Alloys based on copper with nickel or cobalt as the next major constituent
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/04—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of bars or wire
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/02—Making non-ferrous alloys by melting
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/08—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of copper or alloys based thereon

Definitions

  • the invention relates to a copper alloy, in particular to a copper alloy strip with excellent comprehensive properties such as good yield strength, medium conductivity and high elastic modulus, and is mainly used in elastic terminals, electronic components, connectors, and lead frames , Base station and server connectors and other fields.
  • the yield strength of copper alloy strips must be above 850MPa, the conductivity must be above 45% IACS, and the modulus of elasticity must be above 120GPa; in order to be stamped and formed For processing, the copper alloy strip must also have good bending performance. Badway 90° bending R/t ⁇ 2.5 will not crack (R is the bending radius, t is the thickness of the strip).
  • Consumer electronics, electronic components, electronic connectors, connectors, lead frames and other commonly used high-performance copper alloys are mainly CuNiSi series and CuNiCoSi series Corson series copper alloys, including C70250, C70350 and their improved products, Such as NKC388 (C70252), C70350 XE/XS and other alloys.
  • the well-known C70250 strip has a composition of Ni: 2.2-4.2 wt%, Si: 0.25-1.2 wt%, Mg: 0.05-0.3 wt%, and the balance is Cu.
  • its yield strength and electrical conductivity cannot meet the performance requirements of ⁇ 850MPa and ⁇ 45%IACS at the same time.
  • the conductivity of the C70250 strip in the TM03 state can reach more than 45% IACS, its yield strength is below 800MPa;
  • C70250 alloy strips in other states also have the problem that the yield strength and conductivity cannot meet the performance requirements at the same time.
  • C70250 tape cannot meet the performance requirements of small, light, thin, highly integrated, intelligent, and multifunctional consumer electronics, electronic components, electronic connectors and lead frames.
  • Another well-known high-performance copper alloy strip with American standard number C70350 the composition is Ni: 1.0-2.5wt%, Si: 0.5-1.2wt%, Co: 1.0-2.0wt%, Mg: ⁇ 0.15wt% , The balance is Cu.
  • the conductivity of the TM06 strip is 45% IACS, the yield strength ranges from 810 MPa to 920 MPa, the measured yield strength is only about 830 MPa, and the elastic modulus is 120 GPa. Although its yield strength and electrical conductivity are improved compared with C70250, the measured value of its yield strength is only about 830MPa, and its yield strength only meets the current performance requirements of connectors, connectors, and lead frames for copper alloy strips. As electronic products and electronic components become more and more miniaturized, their yield strength will not be able to meet the requirements of this development trend.
  • NKC388 C70252 alloy strip. Its typical composition is Ni: 3.8wt%, Si: 0.8wt%, Mn: 0.13wt%, Mg: 0.1 wt%, the balance is Cu. Although the yield strength of the alloy strip can reach more than 910MPa, its conductivity is only 38% IACS. Due to the low conductivity, the NKC388 strip cannot meet the future development requirements of electronic connectors, connectors, and electronic components.
  • C70350XE/XS alloy strip Another well-known common material for connectors and lead frames is C70350XE/XS alloy strip, the composition of which is within the composition range of C70350 alloy. Although its yield strength can reach more than 880MPa, and the yield strength of C70350 XS state can even reach more than 940 MPa, whether it is C70350 XE state or C70350 XS state, its conductivity is only 40% IACS, which cannot meet the rapid development of electronic connectors and Lead frame requirements for the electrical conductivity of copper alloy strips.
  • the technical problem to be solved by the present invention is to provide a copper alloy strip with excellent comprehensive properties such as high yield strength, high electrical conductivity, high elasticity, excellent bending and the like and a preparation method thereof according to the current state of the art.
  • the technical solution adopted by the present invention to solve the technical problem is: a copper alloy strip with excellent comprehensive performance, characterized in that the weight percentage composition of the copper alloy includes: Ni: 2.5wt% to 4.0wt%, Co: 0.2wt% ⁇ 1.2wt%, Si: 0.4wt% to 1.4wt%, Ag: 0.01wt% to 0.2wt%, the balance being Cu and unavoidable impurities.
  • Ni, Co and Si are the main elements.
  • Ni, Co and Si atoms are dissolved into the copper matrix through high-temperature solid solution treatment, and then quenched to form a supersaturated solid solution, followed by aging treatment to precipitate Ni x Si y and Co x
  • the Si y precipitation phase, the precipitated precipitation phase plays a role of dispersion strengthening, thereby improving the tensile strength, yield strength and elastic modulus of the copper alloy strip of the present invention.
  • Ni, Co and Si atoms are precipitated from the copper matrix in the form of Ni x Si y and Co x Si y precipitation phases, so that the concentration of Ni, Co and Si solute atoms in the copper matrix is greatly reduced and greatly increased
  • the purity of the copper matrix reduces the scattering effect of the solute atoms in the copper matrix on the electron waves, thereby greatly improving the conductivity of the copper matrix.
  • the Ni content is less than 2.5wt%, the Co content is less than 0.2wt%, and the Si content is less than 0.4wt% in the present invention
  • the precipitation of Ni x Si y and Co x Si y precipitated in the copper alloy strip of the present invention The phase is less, and the effect of dispersion strengthening is not obvious.
  • the yield strength of the copper alloy strip of the present invention is less than 850 MPa, and the elastic modulus is less than 120 GPa.
  • Ni content of the present invention is greater than 4.0 wt%, the Co content is greater than 1.2 wt%, and the Si content is greater than 1.4 wt%, too much dispersion strengthening phase is precipitated, and the scattering effect of the second phase particles on the electron wave is enhanced, resulting in the present invention
  • the conductivity of the copper alloy strip is lower than 45% IACS.
  • the composition of Ni, Co and Si in the copper alloy strip of the present invention is optimal in the range of Ni: 2.5wt% to 4.0wt%, Co: 0.2wt% to 1.2wt%, Si: 0.4wt% to 1.4wt% .
  • Ni x Si y and Co x Si y in the copper alloy strip of the present invention form a cross-space distribution, which improves the synergistic strengthening effect of the Ni x Si y precipitation phase and the Co x Si y precipitation phase, which is beneficial to improve the copper of the present invention.
  • Ag is the main element, and the addition range of Ag in the present invention is 0.01% ⁇ 0.2%. Within this addition range, Ag is solid-dissolved in the copper matrix as a substitutional solid solution, and the Ag in the copper matrix is solid-dissolved Atoms play a solid solution strengthening effect to further improve the mechanical properties of the copper alloy strip of the present invention. Also, because the radius difference between Ag atoms and Cu atoms is small, although Ag atoms are solid-soluble in the copper matrix, because Ag atoms and Cu atoms only There is a small difference in atomic radius, a small stress field formed, and a small scattering effect on electron waves.
  • the solid solution of Ag has little effect on the conductivity of the copper alloy strip of the present invention, which can ensure that the copper alloy strip of the present invention
  • the electrical conductivity is above 45% IACS.
  • the Ag content is less than 0.01%, the solid solution strengthening effect is not obvious; if the Ag content exceeds 0.2%, although the solid solution strengthening effect is better, the concentration of Ag atoms is higher. High, the scattering effect of electron waves is enhanced, resulting in the conductivity of the copper alloy strip of the present invention being lower than 45% IACS. Therefore, the Ag content in the copper alloy strip of the present invention is the best in the range of 0.01%-0.2%.
  • Ag atoms can improve the high temperature softening resistance and stress relaxation resistance of the copper alloy strip of the present invention, so that the copper alloy strip of the present invention can be used in consumer electronics and electronic components. , Electronic plug-in devices, connectors, lead frames and other application fields are better used.
  • the texture type and area ratio of the copper alloy strip are as follows: the area ratio of the cubic texture is 10%-30%, the area ratio of the brass texture is 5%-20%, and the copper type The area ratio of the texture is 5%-20%, and the balance is other types of textures.
  • the area ratio of the texture is the ratio of the area within 15° of each orientation deviation angle divided by the measured area.
  • the ratio of cubic texture area in the strip determines the bending performance of the strip.
  • the ratio of cubic texture is higher.
  • the ratio of cubic texture is low, the bending performance of the strip is better.
  • the bending performance is poor; the area ratio of the brass texture and copper texture in the strip has a certain impact on the mechanical properties of the strip.
  • the area of the brass texture and the copper texture are relatively high, the strip
  • the mechanical properties of the strip are relatively high.
  • the area of the brass texture and the copper texture are relatively low, the mechanical properties of the strip are relatively low.
  • the texture of the alloy will change with the progress of the process. During the hot rolling process, a copper-type texture will be formed.
  • part of the copper-type texture will be transformed into brass. Texture.
  • the remaining copper texture in the strip will be transformed into a square texture, and then pre-finishing rolling, primary aging, finishing rolling, and secondary During the aging treatment, the cubic texture will be transformed into the brass texture and copper texture.
  • the cubic texture, brass texture, and copper texture area of the copper alloy strip of the present invention are ensured The proportion satisfies the above range. When the proportion of the texture area of the copper alloy strip of the present invention is within the above range, while ensuring good bending performance, the mechanical properties of the copper alloy strip of the present invention are also higher.
  • the area ratio of the cubic texture to the brass texture and the copper texture of the copper alloy strip satisfies: 0.3 ⁇ a/(b+c) ⁇ 2.0, where a is the area ratio of the cubic texture , B is the area ratio of the brass texture, and c is the area ratio of the copper texture.
  • the content of the cubic texture determines the bending performance of the strip; the content of the brass texture and the copper texture has a certain degree of influence on the mechanical properties of the copper alloy strip of the present invention.
  • the area ratio of cubic texture, brass texture, and copper texture a/(b+c) ⁇ 0.3 the ratio of cubic texture is low, resulting in poor bending performance; when cubic texture
  • the area ratio of brass texture and copper texture a/(b+c)>2 although the bending performance of the strip is very good, the mechanical properties of the strip will be worse. Only when the area ratio of cubic texture, brass texture, and copper texture satisfies 0.3 ⁇ a/(b+c) ⁇ 2.0, the copper alloy strip of the present invention has both good bending performance and High mechanical properties.
  • the copper alloy strip further includes at least one of the optional elements, and the total weight percentage of the optional elements is 0.5wt% or less; the optional elements are Mg: 0.001wt% to 0.2wt%, Ce: 0.001wt% ⁇ 0.2wt%, Cr: 0.001wt% ⁇ 0.1wt%, Zr: 0.001wt% ⁇ 0.1wt%, Ti: 0.001wt% ⁇ 0.1wt%, Fe: 0.001wt% ⁇ 0.2wt%, Mn: 0.001wt% ⁇ 0.2wt%, Zn: 0.001wt% to 0.2wt%, Sn: 0.001wt% to 0.2wt%.
  • the optional elements are Mg: 0.001wt% to 0.2wt%, Ce: 0.001wt% ⁇ 0.2wt%, Cr: 0.001wt% ⁇ 0.1wt%, Zr: 0.001wt% ⁇ 0.1wt%, Ti: 0.001wt% ⁇ 0.1wt%, Fe:
  • the main function of Mg is to dissolve in the copper to play a solid solution strengthening effect, thereby helping to improve the mechanical properties of the copper alloy strip of the present invention.
  • Mg can also improve the resistance to high temperature softening and stress relaxation of the copper alloy strip of the present invention.
  • Mg is easily combined with oxygen, and plays a role of deoxidation in the copper alloy smelting process of the present invention, ensuring that the copper alloy ingot does not contain Ni, Co, Si, Cr, Zr, Ti, Fe, Mn, Zn, Sn
  • the oxides of other elements purify the melt of the copper alloy of the present invention, which is beneficial to improve the product quality of the copper alloy strip.
  • the Mg content is less than 0.001wt%, it cannot improve the mechanical properties, resist high temperature softening and stress relaxation, nor can it fully deoxidize; when the Mg content is higher than 0.2wt%, the excess Mg is solid-soluble In the copper matrix, the heat dissipation of electron waves will be improved, thereby reducing the conductivity of the copper alloy strip of the present invention.
  • the Ce element can be used as a nucleation center to increase the nucleation rate of the copper alloy strip of the present invention, thereby playing the role of grain refinement.
  • the fine-grained ingot provides initial structure conditions for preparing the copper alloy strip finished product with fine-grained grains, and helps to improve the strength and bending performance of the copper alloy strip of the present invention.
  • Ce can also form Ce x Ni y , Ce x Co y , Mg x Ce y and other precipitation phases with Ni, Mg, etc., which play a role of dispersion strengthening.
  • the optimum content of Ce is in the range of 0.001% to 0.2% by weight.
  • Cr and Zr can form a Cr x Zr y precipitation phase, which plays a role of dispersion strengthening, which is beneficial to improve the mechanical properties of the copper alloy strip of the present invention.
  • Ti atoms precipitate Cu x Ti y precipitates through solution quenching and subsequent aging treatment, which play a synergistic dispersion strengthening effect with the precipitated Cr x Zr y , Ni x Si y , Co x Si y and other precipitation phases, which helps To further improve the mechanical properties of the copper alloy strip of the present invention.
  • Fe can form a Fe x Si y precipitation phase with Si, which can reduce the solid solution of Si in the copper matrix while forming the precipitation phase to play a role of dispersion strengthening, which is helpful for improving the conductivity of the copper alloy strip of the present invention.
  • the content of the optional elements Cr, Zr, Ti, and Fe in the copper alloy strip of the present invention is lower than the lower limit, the effect is not obvious; if it exceeds the upper limit, the conductivity of the copper alloy strip of the present invention will be greatly reduced.
  • the Mn, Zn, and Sn in the copper alloy strip of the present invention mainly play a solid solution strengthening effect, and at the same time help to improve the high temperature softening resistance and stress relaxation resistance of the copper alloy strip of the present invention.
  • Mn and Si will also generate Mn x Si y phase, which plays a role of dispersion strengthening and improves the mechanical properties of the strip. If the content of the optional elements Mn, Zn, and Sn in the copper alloy strip of the present invention is lower than the lower limit, the effect is not obvious; if it exceeds the upper limit, the conductivity of the copper alloy strip of the present invention will be greatly reduced.
  • the yield strength of the copper alloy strip is 850 MPa or more
  • the elastic modulus is 120 GPa or more
  • the conductivity is 45% IACS or more
  • the Badway 90° bending R/t ⁇ 2.5 is preferably, the yield strength of the copper alloy strip.
  • the preparation method of the copper alloy strip with excellent comprehensive performance of the present invention is as follows: batching ⁇ melting ⁇ casting ⁇ sawing ⁇ heating ⁇ hot rolling ⁇ milling ⁇ rough rolling ⁇ solution and quenching treatment ⁇ intermediate rolling ⁇ primary aging ⁇ cleaning ⁇ pre-finishing rolling ⁇ secondary aging ⁇ cleaning ⁇ finishing rolling ⁇ stretch-bending straightening; characterized in that the total processing rate of the hot rolling is above 90% and the final rolling temperature is controlled above 840°C and above 900°C Hot rolling is the first stage of hot rolling, and the rolling rate is 60% to 90%; between 900°C and the final rolling temperature of 840°C is the second stage of hot rolling, and the rolling rate is the plate after the first stage of hot rolling. 30%-60% of the thickness of the blank; the copper-type texture area in the strip after the hot rolling process accounts for more than 40%.
  • the melting temperature of the copper alloy is 1250°C to 1300°C, which ensures that the constituent elements are fully melted to form a copper alloy melt with uniform composition.
  • the casting temperature of the copper alloy slab is in the range of 1200°C to 1250°C, and sufficient electromagnetic stirring is performed during the casting process to make the copper alloy melt of the present invention have uniform crystal grains and no obvious columnar crystals when solidified in the mold. Subsequent formation of a specific texture and area ratio in the copper alloy strip provides a uniform initial grain structure.
  • the heating temperature of the hot rolling of the invention is 1000°C-1020°C, and the heating and holding time is 2h-4h.
  • the elements such as Ni, Co, Si, Ag, Mg, Ce, Cr, Zr, Ti, Fe, Mn, Zn, Sn in the copper alloy strip of the present invention can all enter into solid solution In the copper matrix, it is ensured that no intermetallic compounds exist during the hot rolling and blooming of the copper alloy strip of the present invention, thereby ensuring uniform deformation and no cracking of the copper alloy ingot during the hot rolling and blooming.
  • the hot-rolling billet temperature is lower than 1000°C, the specific hot-rolling process described in the present invention cannot be guaranteed.
  • the heating and holding time is 2h to 4h, which can ensure that the alloying elements are fully dissolved into the copper matrix and the crystal grains do not grow up.
  • the heating and holding time is less than 2h, and some solute atoms cannot be dissolved into the copper matrix due to insufficient diffusion; the holding time exceeds 4h, the crystal grains will grow, and the copper alloy slab will crack during the hot rolling process.
  • the total processing rate of hot rolling is above 90%, and the first stage of hot rolling with a processing rate of 60% to 90% before the temperature drops to 900°C;
  • the rolling rate is 30% to 60% of the thickness of the slab after the first stage of hot rolling. In the range of 1000°C ⁇ 1020°C, all the solute atoms are dissolved in the copper matrix.
  • the distortion energy of the first stage of hot rolling is too large, which is not conducive to the copper texture during the second stage of hot rolling. form.
  • a hot rolling process with a processing rate of 30%-60% is performed between 900°C and 840°C, the appropriate distortion energy formed before can induce the formation of a copper-type texture.
  • a copper-type texture with an area of more than 40% can be formed in the copper alloy strip of the present invention, which is a specific method for the formation of subsequent finished strips. Prepare for the texture and area ratio.
  • the copper alloy strip with a copper-type texture of more than 40% formed in the present invention after subsequent deformation and heat treatment, forms a cubic texture and a copper-type texture with a specific area ratio in the copper alloy strip of the present invention , Brass texture, so that the copper alloy strip of the present invention has high yield strength, high conductivity, high elastic modulus, and its bending performance is also excellent.
  • the total processing rate of the rough rolling is controlled at 80% or more.
  • the total rough rolling processing rate of more than 80% can store sufficient strain energy in the copper alloy strip of the present invention, so that a cubic texture of more than 35% can be formed during the subsequent solution and quenching treatment. If the rough rolling processing rate is less than 80%, due to insufficient energy storage, sufficient cubic texture cannot be formed during solution and quenching treatment, resulting in the texture type and the area ratio in the finished strip can not meet the requirements. The bending performance of the finished strip is poor.
  • the solution quenching temperature is controlled at 950°C to 1040°C
  • the holding time is 0.1h to 1h
  • the solution heating rate must be above 100°C/s
  • the quenching cooling rate must be above 150°C/s.
  • the area of the cubic texture in the strip after melting takes up more than 35%.
  • the solution heating temperature of the present invention is set at 950°C ⁇ 1040°C.
  • One is to ensure that the copper-type texture formed during hot rolling is transformed into a cubic texture during the solution treatment of the strip and to ensure the formation of a cubic texture of more than 35%.
  • the second is to ensure that the solute atoms precipitated during the hot-rolling billeting process are re-solid-dissolved into the copper matrix to form a supersaturated solid solution, which facilitates the precipitation of enough precipitate phases in the subsequent aging process, and ensures that the yield strength of the strip reaches more than 850MPa.
  • the holding time is 0.1h to 1h, and the purpose is to allow the solute atoms to have sufficient time to diffuse during the solid solution process to form a supersaturated solid solution.
  • the solid solution heating rate must be guaranteed to be above 100°C/s to ensure the conversion of copper texture to cubic texture; the quenching cooling rate must be above 150°C/s to ensure that no solute atoms are precipitated during the quenching process, thereby forming a supersaturated solid solution.
  • the solid solution temperature of the present invention can be set at 980°C to 1040°C.
  • the processing rate of the intermediate rolling is controlled at 20%-65%; the processing rate of the pre-finishing rolling after the primary aging is controlled at 10%-40%, and the processing rate of the finishing rolling after the secondary aging is controlled at 5 % ⁇ 20%.
  • the processing rate of the intermediate rolling is lower than 20%, sufficient internal energy cannot be reserved for the primary aging, and the primary aging is insufficient, resulting in the yield strength of the finished copper alloy strip of the present invention being lower than 850MPa; the processing rate of the intermediate rolling is greater than 65 %, most of the cubic texture formed during the solution quenching treatment will be converted into a brass texture, resulting in poor bending performance of the finished strip.
  • the first-stage aging temperature is 400°C to 500°C, and the holding time is 5h-8h; the second-stage aging temperature is in the range of 300°C to 400°C, and the holding time is 2h-5h.
  • the copper alloy strip of the present invention has a primary aging temperature of 400°C to 500°C, and a heat preservation time of 5h to 8h.
  • the present invention sets the first-stage aging temperature to 400°C to 500°C, and its function is to cause the supersaturated solid solution to undergo a solid phase change, and to initially precipitate some precipitated phase particles.
  • these preliminary precipitated particles A large number of dislocations are formed at the center, providing solute atom diffusion channels for the secondary aging of the strip, which is conducive to the formation of Ni x Si y , Co x Si y , Cr x Zr y and Cu x Ti y during secondary aging. Wait for the dispersion to strengthen the phase.
  • the diffusion rate of solute atoms is slow, and the required amount of precipitation phase cannot be precipitated from the supersaturated solid solution;
  • the first-stage aging temperature is higher than 500°C, the precipitation phase particles precipitated by the first-stage aging will occur It grows up, resulting in a decrease in the number of particles in the precipitation phase, which is not conducive to the improvement of mechanical properties.
  • the purpose of the holding time of 5h to 8h is to allow enough time for the solute atoms to diffuse during the first aging, so as to precipitate the required dispersion strengthening phase from the supersaturated solid solution.
  • the total processing rate of the pre-finishing rolling of the copper alloy strip of the present invention after primary aging is 10%-40%. If the total processing rate of the pre-finishing rolling after the primary aging is less than 10%, it is impossible to form enough dislocations around the precipitation phase precipitated by the primary aging, which will affect the precipitation of the secondary aging precipitation phase, resulting in the failure of the finished strip.
  • the yield strength cannot reach more than 850MPa; if the total processing rate of the pre-finishing rolling after the first aging exceeds 40%, most of the cubic texture in the strip will be transformed into a brass texture, resulting in poor bending performance of the finished strip .
  • the copper alloy strip of the present invention is subjected to secondary aging after pre-finishing rolling, the secondary aging temperature is in the range of 300°C to 400°C, and the holding time is 2h to 5h.
  • the pre-finish rolling process after the first aging process will form a large number of dislocations around the precipitate phase precipitated by the first aging.
  • the second aging process will use the dislocations around the precipitate phase precipitated by the first
  • a secondary aging precipitation phase with planetary distribution is formed around the precipitation phase precipitated by aging.
  • the particles of the primary aging sedimentation phase will partially grow up, thus forming a distribution morphology of the secondary aging sedimentation phase with a planetary distribution around the larger primary aging sedimentation phase particles as the center.
  • the synergistic strengthening effect of the primary aging precipitation phase particles and the secondary aging precipitation phase particles can greatly improve the mechanical properties of the copper alloy strip of the present invention, and ensure that the yield strength reaches more than 850 MPa.
  • the secondary aging temperature is lower than 300°C, due to the low temperature, the diffusion rate of solute atoms during secondary aging is slow, and the precipitation strengthening phase cannot be effectively precipitated;
  • the secondary aging temperature is higher than 400°C, the primary aging and secondary aging The precipitation phase precipitated by the first-stage aging will grow up greatly, and the synergistic strengthening effect between the first-stage aging precipitation phase particles and the second-stage aging precipitation phase particles cannot be fully exerted, resulting in the mechanical properties of the strip not reaching more than 850MPa.
  • the secondary aging holding time is 2h-5h. If the holding time is less than 2h, enough secondary aging precipitation phase particles cannot be formed, which is detrimental to the mechanical properties; if the holding time exceeds 5h, the primary aging and the second The precipitation phase precipitated by aging will grow excessively, resulting in the deterioration of the synergistic strengthening effect and the decrease of the mechanical properties of the strip.
  • the copper alloy strip is subjected to finish rolling processing after secondary aging, and the total processing rate of the finish rolling processing is 5%-20%. If the total processing rate of the finishing rolling is less than 5%, the mechanical properties of the strip cannot be further improved; if the total processing rate of the finishing rolling is higher than 20%, although the mechanical properties of the strip can be further improved, the mechanical properties of the strip can be further improved.
  • the cubic texture in the material is further transformed into the brass texture, resulting in the area of the cubic texture accounting for less than 10%, and the bending performance of the strip will drop sharply.
  • the copper alloy strip of the present invention is subjected to stretch-bending and straightening treatment after finishing rolling, so as to improve the shape of the strip.
  • Ni, Co and Si are the main elements. Ni, Co and Si atoms are dissolved into the copper matrix through high-temperature solid solution treatment, and then quenched to form a supersaturated solid solution, followed by aging treatment to precipitate NixSiy and CoxSiy precipitate phases , The precipitated precipitation phase plays a role of dispersion strengthening, thereby improving the tensile strength, yield strength and elastic modulus of the copper alloy strip of the present invention.
  • Ag is the main additive element, and Ag atoms are present in the copper alloy of the present invention in the form of substitutional solid solution, which provides an initial texture basis for the formation of a specific texture and area ratio in the copper alloy strip of the present invention. In addition to the solid solution strengthening effect of Ag in the present invention, Ag atoms can improve the high temperature softening resistance and stress relaxation resistance of the copper alloy strip of the present invention, so that the present invention can achieve excellent comprehensive performance.
  • the yield strength of the copper alloy strip of the present invention is more than 850MPa, the modulus of elasticity is more than 120GPa, the conductivity is more than 45% IACS, and Badway 90° bending R/t ⁇ 2.5, which can meet the requirements of consumer electronics, electronic components, and electronics.
  • the performance requirements of connectors and lead frames are small, light and thin, highly integrated, intelligent, and multifunctional.
  • the whole process of the preparation process of the copper alloy strip with excellent comprehensive performance of the present invention is: batching ⁇ melting ⁇ casting ⁇ sawing ⁇ heating ⁇ hot rolling ⁇ milling ⁇ rough rolling ⁇ solution and quenching treatment ⁇ intermediate rolling ⁇ primary aging ⁇ Cleaning ⁇ pre-finishing rolling ⁇ secondary aging ⁇ cleaning ⁇ finishing rolling ⁇ stretch bending and straightening, specifically including the following steps:
  • Hot rolling The ingot is heated at 1010°C and held for 3 hours before hot rolling and billeting.
  • the total processing rate before 900°C is 60% to 90%, and the total processing rate between 900°C and 840°C is 30 % ⁇ 60% hot-rolling method for hot-rolling processing.
  • Rough rolling After milling the surface of the hot-rolled strip, rough rolling is performed, and the total processing rate of the rough rolling is more than 80%.
  • Solution and quenching treatment After rough rolling, the strip is subjected to solution quenching treatment, the solution temperature is 950°C ⁇ 1040°C, the temperature is held for 0.5h, and then the quenching treatment is carried out.
  • the solution heating rate is 120°C/s, and the cooling rate is 150°C/s.
  • Middle rolling the strip after solution treatment and quenching is subjected to middle rolling, and the middle rolling processing rate is 40%.
  • First-level aging The first-level aging treatment is carried out on the strip after the middle rolling, the aging temperature is between 400 °C and 500 °C, and the aging time is 6 hours.
  • Pre-finishing rolling is performed on the strip after the primary aging treatment, and the processing rate is 30%.
  • Two-stage aging the strip after pre-finish rolling is subjected to two-stage aging treatment, the aging temperature is in the range of 300°C ⁇ 400°C, and the aging time is 3h.
  • Finishing rolling is performed on the strip after the secondary aging treatment, and the processing rate is 5%-20%.
  • Stretch-bend straightening Stretch-bend and straighten the strip after finishing rolling to improve the shape of the strip and obtain a finished copper alloy strip with excellent comprehensive performance.
  • the finished strips of the examples were subjected to room temperature tensile mechanical properties, electrical conductivity, texture type and area ratio, and Badway 90° bending tests; and compared with the properties of the comparative alloy.
  • the room temperature tensile test was carried out on the electronic universal testing machine in accordance with "GB/T 228.1-2010 Metallic Materials Tensile Test Part 1: Room Temperature Test Method".
  • the sample and comparative examples were tested with strips with a thickness of 0.2mm. In this way, the stretching speed is 5mm/min.
  • JCBA T307-2007 Test method of bend formability for sheets and strips of copper and copper alloys to test the bending performance of the strips of the embodiment and the comparative example (evaluate whether the bend is cracked by Badway 90°R/t ⁇ 2.5) ,
  • the width of the test strip is 10mm.
  • EBSD was used to analyze the texture type and area ratio of the strips of the examples and comparative examples.
  • area ratio of each orientation refers to the ratio of the area within 15° of the deviation angle of each orientation divided by the measured area.
  • the yield strength of the C70250 alloy strip is only 650.2 MPa, which is lower than the yield strength of the alloy strip of the present invention.

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Abstract

一种综合性能优异的铜合金带材，该铜合金的重量百分比组成包括：Ni：2.5wt％～4.0wt％，Co：0.2wt％～1.2wt％，Si：0.4wt％～1.4wt％，Ag：0.01wt％～0.2wt％，余量为Cu。铜合金带材屈服强度达850MPa以上、弹性模量达120GPa以上、导电率达45％IACS以上，在具有高的屈服强度的同时，该板带材具有良好的折弯性能，Badway 90°折弯R/t≤2.5不开裂(R为折弯半径、t为带材厚度)，是生产制造电子接插件、连接器、电子零部件与引线框架的理想材料。

Description

一种综合性能优异的铜合金带材及其制备方法 技术领域
本发明涉及铜合金，具体涉及一种具有良好的屈服强度、中等导电率和较高弹性模量等综合性能优异的铜合金带材，主要应用于弹性端子、电子元器件、接插件、引线框架、基站及服务器用连接器等领域。
背景技术
随着芯片技术、5G通信、消费电子、物联网、工业机器人、人工智能、新能源汽车、航空航天、高速铁道交通等的飞速发展，芯片用引线框架、通信设备、高端制造业、消费电子用连接器、电子元器件等对铜合金板带材的综合性能提出了越来越高的要求。电子产品及电子元器件向小型化、智能化、多功能化、高度集成化方向发展，电子元器件在保证高可靠性信号传输的同时，对散热也提出了越来越高的要求，因此要求用来制备电子元器件的铜合金带材在具有高的屈服强度、大的弹性模量的同时，要求其导电率也必须保持在一定的性能水平。为了满足电子产品及电子元器件小型化、高度集成化的要求，铜合金带材的屈服强度必须达到850MPa以上、导电率必须达到45％IACS以上、弹性模量必须在120GPa以上；为了能冲压成形加工，铜合金带材还必须具有良好的折弯性能，Badway 90°折弯R/t≤2.5不开裂(R为折弯半径，t为带材厚度)。
消费电子、电子元器件、电子接插件、连接器、引线框架等常用的高性能铜合金主要是以CuNiSi系及CuNiCoSi系为主的Corson系列的铜合金，包括C70250、C70350及他们的改进产品，比如NKC388(C70252)、C70350 XE/XS等合金。
公知的C70250带材，成分为Ni：2.2～4.2wt％，Si：0.25～1.2wt％，Mg：0.05～0.3wt％，余量为Cu。在其所有的产品状态中，其屈服强度与导电率无法同时满足≥850MPa与≥45％IACS的性能要求。虽然C70250带材TM03态的导电率可以达到45％IACS以上，但其屈服强度在800MPa以下；其他状态的C70250合金带材同样存在屈服强度与导电率不能同时满足性能要求的问题。基于以上原因，C70250带材无法满足消费电子、电子元器件、电子接插件及引线框架的小型、轻薄、高度集成化、智能化、多功能化的性能要求。
另一种公知的美标牌号为C70350的高性能铜合金带材，成分为Ni：1.0-2.5wt％，Si：0.5-1.2wt％，Co：1.0-2.0wt％，Mg：≤0.15wt％，余量为Cu。其TM06态带材的导电率为45％IACS，屈服强度范围为810MPa至920MPa，屈服强度的实测值只有830MPa左右，弹性模量为120GPa。虽然其屈服强度和导电率与C70250相比均有所提高，但其屈服强度实测值只有830MPa左右，其屈服强度只满足接插件、连接器、引线框架对铜合金带材的现阶段的 性能要求，随着电子产品及电子元器件越来越小型化，其屈服强度将无法满足这种发展趋势的要求。
另一种公知的用于电子接插件及引线框架的铜合金为NKC388(C70252)合金带材，其典型成分为Ni：3.8wt％，Si：0.8wt％，Mn：0.13wt％，Mg：0.1wt％，余量为Cu。虽然该合金带材的屈服强度可以达到910MPa以上，但其导电率只有38％IACS，由于导电率偏低，NKC388带材也无法满足电子接插件、连接器、电子元器件等的未来发展要求。
另一种公知的连接器与引线框架常用材料为C70350XE/XS合金带材，其成分在C70350合金的成分范围内。虽然其屈服强度可以达到880MPa以上，C70350 XS态屈服强度甚至可以达到940MPa以上，但无论是C70350 XE态还是C70350 XS态带材，其导电率只有40％IACS，不能满足飞速发展的电子接插件与引线框架对铜合金带材的导电性能的要求。
显然现有的合金材料仍不能满足消费电子、电子元器件、电子接插件、连接器、引线框架行业快速发展对于高性能铜合金材料的需求。
发明内容
本发明所要解决的技术问题是针对当前技术的现状提供一种满足高的屈服强度、高导电率、高弹性、优良的折弯等综合性能优异的铜合金带材及其制备方法。
本发明解决技术问题所采用的技术方案是：一种综合性能优异的铜合金带材，其特征在于该铜合金的重量百分比组成包括：Ni：2.5wt％～4.0wt％，Co：0.2wt％～1.2wt％，Si：0.4wt％～1.4wt％，Ag：0.01wt％～0.2wt％，余量为Cu和不可避免的杂质。
本发明中Ni、Co与Si为主要元素，Ni、Co与Si原子通过高温固溶处理溶入铜基体中，然后通过淬火处理形成过饱和固溶体，后续通过时效处理析出Ni xSi y与Co xSi y沉淀相，析出的沉淀相起弥散强化作用，从而提高本发明铜合金带材的抗拉强度、屈服强度与弹性模量。又由于时效处理使Ni、Co与Si原子以Ni xSi y与Co xSi y沉淀相的方式从铜基体中析出，使铜基体中的Ni、Co与Si溶质原子浓度大幅降低，大大提高了铜基体的纯净度，降低了铜基体中溶质原子对电子波的散射作用，从而使铜基体的导电率得到大幅提高。当本发明中Ni含量少于2.5wt％、Co含量少于0.2wt％、Si含量少于0.4wt％时，本发明的铜合金带材中时效析出的Ni xSi y与Co xSi y沉淀相较少，弥散强化的效果不明显，本发明的铜合金带材的屈服强度低于850MPa、弹性模量小于120GPa。而当本发明的Ni含量大于4.0wt％、Co含量大于1.2wt％、Si含量大于1.4wt％时，析出的弥散强化相太多，第二相粒子对电子波的散射作用增强，导致本发明的铜合金带材的导电率低于45％IACS。本发明铜合金带材中的Ni、Co与Si的成分在Ni：2.5wt％～4.0wt％、Co：0.2wt％～1.2wt％、Si：0.4wt％～1.4wt％范围内为最佳。此外，本发明铜合金带材中的Ni xSi y与Co xSi y形成交叉间隔分布，提高了Ni xSi y沉淀相与Co xSi y沉淀相的协同强化效果，有利于提高本发明铜合金带材的力学性能。
本发明中Ag为主要元素，本发明中Ag的添加范围为0.01％～0.2％，在该添加范围内， Ag以置换式固溶体的方式固溶于铜基体中，固溶于铜基体中的Ag原子起固溶强化作用，进一步提高本发明铜合金带材的力学性能，又由于Ag原子与Cu原子的半径差异不大，虽然Ag原子固溶于铜基体中，但由于Ag原子与Cu原子只存在较小的原子半径差异，形成的应力场较小，对电子波的散射作用较小，因此Ag的固溶对本发明铜合金带材的导电率影响较小，可以确保本发明铜合金带材的导电率达到45％IACS以上。在本发明的铜合金带材中，如果Ag的含量低于0.01％，则固溶强化效果不明显；如果Ag的含量超过0.2％，虽然固溶强化效果更好，但由于Ag原子的浓度较高，对电子波的散射作用增强，导致本发明铜合金带材的导电率低于45％IACS，因此本发明铜合金带材中的Ag含量在0.01％-0.2％范围内为最佳。Ag在本发明中除了起固溶强化作用外，Ag原子可以提高本发明铜合金带材的抗高温软化能力及抗应力松弛能力，使本发明的铜合金带材可以在消费电子、电子元器件、电子接插器件、连接器、引线框架等应用领域得到更好地应用。
作为优选，该铜合金带材的织构类型及其面积占比如下：立方织构的面积占比为10％～30％、黄铜织构的面积占比为5％～20％、铜型织构的面积占比为5％～20％、余量为其他类型的织构，织构面积占比为各取向偏离角度15°以内的面积除以测定面积的比值。
带材中的立方织构面积占比决定了带材的折弯性能，当立方织构比例较高时，带材的折弯性能较好，当立方织构比例较低时，带材的折弯性能较差；带材中的黄铜织构及铜型织构面积占比对带材的力学性能有一定的影响，当黄铜织构与铜型织构面积占比较高时，带材的力学性能相对较高，当黄铜织构与铜型织构面积占比较低时，带材的力学性能相对较低。在加工过程中，合金的织构会随着工艺的进程发生转变，在热轧加工过程中会形成铜型织构，在进行后续的粗轧加工时，部分铜型织构会转化成黄铜织构，当粗轧加工后进行高温固溶淬火时，带材中剩下的铜型织构会转化成立方织构，然后再进行预精轧加工、一级时效、精轧加工、二级时效处理时，立方织构会向黄铜织构及铜型织构转化，通过控制整个形变热处理过程，确保本发明铜合金带材的立方织构、黄铜织构、铜型织构的面积占比满足上述范围。当本发明铜合金带材的织构面积占比在上述范围内时，在保证良好的折弯性能的同时，本发明的铜合金带材的力学性能也较高。
作为优选，该铜合金带材的立方织构与黄铜织构、铜型织构的面积占比满足：0.3≤a/(b+c)≤2.0，其中a为立方织构的面积占比，b为黄铜织构的面积占比，c为铜型织构的面积占比。
本发明的铜合金带材，立方织构的含量决定了带材的折弯性能；黄铜织构与铜型织构的含量，对本发明铜合金带材的力学性能有一定程度的影响。当立方织构、黄铜织构、铜型织构的面积占比a/(b+c)＜0.3时，由于立方织构的占比偏低，导致折弯性能变差；当立方织构、黄铜织构、铜型织构的面积占比a/(b+c)＞2时，虽然带材的折弯性能非常优异，但带材的力学性能会变差。只有当立方织构、黄铜织构、铜型织构的面积占比满足0.3≤a/(b+c)≤2.0时，本发明的铜合金带材既有良好的折弯性能，又具有高的力学性能。
作为优选，该铜合金带材还包括可选元素中的至少一种，可选元素重量百分比组成总计 0.5wt％以下；可选元素为Mg：0.001wt％～0.2wt％、Ce：0.001wt％～0.2wt％、Cr：0.001wt％～0.1wt％、Zr：0.001wt％～0.1wt％、Ti：0.001wt％～0.1wt％、Fe：0.001wt％～0.2wt％、Mn：0.001wt％～0.2wt％、Zn：0.001wt％～0.2wt％、Sn：0.001wt％～0.2wt％。
其中Mg的主要作用是固溶于铜中起固溶强化的作用，从而有利于提高本发明铜合金带材的力学性能。Mg还可以提高本发明铜合金带材的抗高温软化及抗应力松弛的能力。此外，Mg很容易与氧结合，在本发明的铜合金熔炼过程中起脱氧的作用，确保铜合金铸锭中不含Ni、Co、Si、Cr、Zr、Ti、Fe、Mn、Zn、Sn等元素的氧化物，净化本发明铜合金的熔体，有利于提高铜合金带材的产品质量。当Mg含量低于0.001wt％时，不能起提升力学性能、抗高温软化与抗应力松弛的能力，也不能起充分脱氧的作用；当Mg含量高于0.2wt％时，多余的Mg固溶于铜基体中，会提高对电子波的散热，从而会降低本发明铜合金带材的导电性能。
本发明的铜合金在熔铸过程中，Ce元素可以作为形核中心而提高本发明铜合金带材的形核率，从而起细化晶粒的作用。晶粒细小的铸锭为制备晶粒细小的铜合金带材成品提供了初始组织条件，有助于提升本发明铜合金带材的强度及折弯性能。此外，Ce还能与Ni、Mg等形成Ce xNi y、Ce xCo y、Mg xCe y等沉淀相，起弥散强化作用。当Ce的含量低于0.001wt％时，晶粒细化效果不明显，当其含量高于0.2wt％时，过量的Ce会导致本发明带材热轧开坯时开裂。因此，Ce的最佳含量范围为0.001％～0.2wt％。
Cr与Zr可以形成Cr xZr y沉淀相，起弥散强化作用，有利于提高本发明铜合金带材的力学性能。本发明中Ti原子通过固溶淬火及后续的时效处理析出Cu xTi y沉淀相，与析出的Cr xZr y、Ni xSi y、Co xSi y等沉淀相起协同弥散强化作用，有助于进一步提高本发明铜合金带材的力学性能。本发明中Fe可以与Si形成Fe xSi y沉淀相，在形成沉淀相起弥散强化作用的同时，可以减少铜基体中固溶的Si，对提升本发明铜合金带材的导电率有帮助。本发明铜合金带材中的可选元素Cr、Zr、Ti、Fe的含量如果低于下限，则作用不明显；如果超过上限，则会大幅降低本发明铜合金带材的导电率。
本发明铜合金带材中的Mn、Zn、Sn主要起固溶强化作用，同时有利于提升本发明铜合金带材的抗高温软化及抗应力松弛能力。Mn与Si还会生成Mn xSi y相，起弥散强化作用，提高带材的力学性能。本发明铜合金带材中的可选元素Mn、Zn、Sn的含量如果低于下限，则作用不明显；如果超过上限，则会大幅降低本发明铜合金带材的导电率。
作为优选，该铜合金带材的屈服强度为850MPa以上、弹性模量为120GPa以上、导电率为45％IACS以上、Badway 90°折弯R/t≤2.5。
本发明综合性能优异的铜合金带材的制备方法，制备流程如下：配料→熔炼→铸造→锯切→加热→热轧→铣面→粗轧→固溶与淬火处理→中轧→一级时效→清洗→预精轧→二级时效→清洗→精轧→拉弯矫直；其特征在于，所述热轧的总加工率在90％以上且终轧温度控制在840℃以上，900℃以上热轧为第一段热轧加工，轧制率为60％～90％；900℃至终轧温度840℃之间为第二段热轧加工，轧制率为第一段热轧加工后板坯厚度的30％～60％；所述热轧 加工后带材中的铜型织构面积占比在40％以上。
本发明中，铜合金的熔炼温度为1250℃～1300℃，确保各成分元素充分熔化，形成成分均匀的铜合金熔体。铜合金板坯的铸造温度在1200℃～1250℃范围内，铸造过程中进行充分的电磁搅拌，使本发明的铜合金熔体在结晶器内凝固时晶粒均匀且无明显的柱状晶，为后续在铜合金带材中形成特定的织构及面积占比提供均匀的初始晶粒组织。
本发明热轧加热温度为1000℃～1020℃，加热保温时间为2h～4h。在1000℃～1020℃温度范围内，本发明铜合金带材中的Ni、Co、Si、Ag、Mg、Ce、Cr、Zr、Ti、Fe、Mn、Zn、Sn等元素都可固溶进入铜基体中，确保本发明铜合金带材热轧开坯时无金属间化合物存在，从而确保热轧开坯时铜合金铸锭的均匀变形且不开裂。当热轧开坯温度低于1000℃时，无法保证本发明所述的特定的热轧加工。当热轧温度高于1020℃时，有可能出现过热或过烧，从而导致热轧开裂。加热保温时间为2h～4h，可确保合金元素充分溶入铜基体且晶粒不发生长大现象。加热保温时间低于2h，部分溶质原子由于扩散不充分而无法溶入铜基体；保温时间超过4h，晶粒会发生长大，铜合金板坯在热轧过程中会发生开裂。
热轧总加工率在90％以上，温度下降至900℃之前进行加工率为60％～90％的第一段热轧加工；终轧温度须保持在840℃以上，在900℃至840℃之间进行第二段热轧加工，轧制率为第一段热轧加工后板坯厚度的30％～60％。在1000℃～1020℃范围内，溶质原子全部固溶于铜基体中，此时本发明的铜合金中只有α相，且由于Ag原子与Cu原子的原子半径差异不大，经过加工率为60％～90％的第一段热轧加工，在Ag原子周围由于热轧加工会形成合适的畸变能，这种由于Ag原子与Cu原子存在原子半径差而在Ag原子周围形成的合适的畸变能，结合本发明铜合金带材的两段式热轧工序及工艺，在热轧后的带材中会形成面积占比40％以上的铜型织构。但当温度低于900℃进行第一阶段热轧加工时，由于沉淀相的析出，导致第一阶段热轧加工的畸变能过大，不利于第二阶段热轧加工过程中铜型织构的形成。当在900℃至840℃之间进行加工率为30％～60％的热轧加工时，之前形成的合适的畸变能会诱导铜型织构的形成。由于Ag的加入，且经过本发明所述的两段式热轧加工，可以在本发明的铜合金带材中形成面积占比40％以上的铜型织构，为后续成品带材中形成特定的织构及面积占比做准备。本发明所述的形成了40％以上的铜型织构的铜合金带材，经过后续的形变热处理，在本发明的铜合金带材中形成特定面积占比的立方织构、铜型织构、黄铜织构，从而使本发明的铜合金带材在具有高的屈服强度、高的导电率、高的弹性模量的同时，其折弯性能同样优异。
作为优选，所述粗轧的总加工率控制在80％以上。
80％以上的粗轧总加工率可以在本发明的铜合金带材中储备足够的应变能，从而在进行后续的固溶并淬火处理时可以确保形成35％以上的立方织构。如果粗轧加工率低于80％，由于储能不够，无法在固溶并淬火处理时形成足够多的立方织构，导致制备的成品带材中织构类型及其面积占比无法达到要求，使带材成品的折弯性能较差。
作为优选，所述固溶淬火温度控制在950℃～1040℃，保温时间为0.1h～1h，固溶升温速 度须在100℃/s以上，淬火冷却速度在150℃/s以上，所述固溶后带材中立方织构的面积占比在35％以上。
本发明的固溶加热温度设置为950℃～1040℃，一是确保带材在固溶处理时促使热轧时形成的铜型织构向立方织构转化且确保形成35％以上的立方织构，二是确保热轧开坯加工过程中析出的溶质原子重新固溶进入铜基体中形成过饱和固溶体，便于后续时效过程中析出足够多的沉淀相，确保带材的屈服强度达到850MPa以上。保温时间为0.1h～1h，目的是使固溶过程中溶质原子有充分扩散的时间，形成过饱和固溶体。保温时间低于0.1h，会导致溶质原子固溶不充分；保温时间超过1h，会导致晶粒过分粗大，影响带材成品的折弯性能。固溶升温速度须保证在100℃/s以上，确保铜型织构向立方织构转化；淬火冷却速度须在150℃/s以上，确保淬火过程中无溶质原子析出，从而形成过饱和固溶体。作为进一步优选，本发明的固溶温度可以设置为980℃～1040℃。
作为优选，所述中轧的加工率控制在20％～65％；所述一级时效后预精轧的加工率控制在10％～40％，二级时效后精轧的加工率控制在5％～20％。
中轧的加工率低于20％，则无法为一级时效储备足够的内能，一级时效不充分，导致本发明铜合金带材成品的屈服强度低于850MPa；中轧的加工率大于65％，则固溶淬火处理时形成的立方织构大部分会转化成黄铜织构，从而导致带材成品的折弯性能较差。
作为优选，所述一级时效温度为400℃～500℃，保温时间为5h～8h；二级时效温度在300℃～400℃范围内，保温时间为2h～5h。
本发明的铜合金带材，其一级时效温度为400℃～500℃，保温时间为5h～8h。本发明将一级时效温度设置为400℃～500℃，其作用是使过饱和固溶体发生固态相变，初步析出部分沉淀相粒子，在随后的预精轧加工过程中，以这些初步析出的粒子为中心形成大量位错，为带材的二级时效提供溶质原子扩散通道，有利于二级时效时溶质原子充分析出形成Ni xSi y、Co xSi y、Cr xZr y与Cu xTi y等弥散强化相。一级时效温度低于400℃时，溶质原子扩散速度较慢，无法从过饱和固溶体中析出需要的沉淀相数量；一级时效温度高于500℃时，一级时效析出的沉淀相颗粒会发生长大，导致沉淀相颗粒数量减少，不利于力学性能的提高。保温时间为5h～8h的目的是使一级时效时溶质原子有足够的时间发生扩散，从而从过饱和固溶体中析出所需要的弥散强化相。
本发明铜合金带材一级时效后的预精轧的总加工率为10％～40％。如果一级时效后预精轧的总加工率低于10％，则无法在一级时效析出的沉淀相周围形成足够多的位错，从而影响二级时效沉淀相的析出，导致带材成品的屈服强度达不到850MPa以上；如果一级时效后预精轧的总加工率超过40％，带材中的立方织构大部分转变为黄铜织构，导致带材成品的折弯性能变差。
本发明的铜合金带材在预精轧加工后进行二级时效，二级时效温度在300℃～400℃范围内，保温时间为2h～5h。一级时效后的预精轧加工，会在一级时效析出的沉淀相周围形成大 量的位错，二级时效会以这些一级时效析出的沉淀相周围的位错为析出通道，在一级时效析出的沉淀相周围形成行星状分布的二级时效沉淀相。在二级时效过程中，一级时效沉淀相粒子会发生部分长大，从而形成以较大的一级时效沉淀相粒子为中心、周边存在呈行星状分布的二级时效沉淀相的分布形态，这种一级时效沉淀相粒子与二级时效沉淀相粒子的协同强化作用可大幅提高本发明铜合金带材的力学性能，确保屈服强度达到850MPa以上。当二级时效温度低于300℃时，由于温度较低，二级时效时溶质原子的扩散速率慢，无法有效析出沉淀强化相；当二级时效温度高于400℃时，一级时效及二级时效析出的沉淀相会发生大幅长大，无法充分发挥一级时效沉淀相粒子与二级时效沉淀相粒子之间的协同强化作用，导致带材的力学性能无法达到850MPa以上。本发明中二级时效保温时间为2h～5h，如果保温时间低于2h，无法形成足够多的二级时效沉淀相粒子，对力学性能不利；如果保温时间超过5h，则一级时效与二级时效析出的沉淀相都会过度长大，导致协同强化效果变差，从而导致带材的力学性能下降。
本发明中铜合金带材在二级时效后进行精轧加工，精轧加工的总加工率为5％～20％。如果精轧加工的总加工率低于5％，带材的力学性能无法获得进一步上升；如果精轧加工的总加工率高于20％，虽然带材的力学性能可获得进一步提升，但由于带材中的立方织构进一步转化成黄铜织构导致立方织构的面积占比低于10％，带材的折弯性能会急剧下降。
本发明的铜合金带材在精轧加工后进行拉弯矫直处理，提高带材的板形。
与现有公知的技术相比，本发明的优点在于：
1、本发明中Ni、Co与Si为主要元素，Ni、Co与Si原子通过高温固溶处理溶入铜基体中，然后通过淬火处理形成过饱和固溶体，后续通过时效处理析出NixSiy与CoxSiy沉淀相，析出的沉淀相起弥散强化作用，从而提高本发明铜合金带材的抗拉强度、屈服强度与弹性模量。Ag作为主添加元素，Ag原子以置换式固溶的方式存在于本发明的铜合金中，为本发明铜合金带材中形成特定的织构及面积占比提供了初始织构基础。Ag在本发明中除了起固溶强化作用外，Ag原子可以提高本发明铜合金带材的抗高温软化能力及抗应力松弛能力，使本发明取得优异的综合性能。
2、本发明铜合金带材的屈服强度为850MPa以上、弹性模量为120GPa以上、导电率为45％IACS以上、Badway 90°折弯R/t≤2.5，满足消费电子、电子元器件、电子接插件及引线框架的小型、轻薄、高度集成化、智能化、多功能化的性能要求。
具体实施方式
以下结合实施例与对比例对本发明作进一步详细描述。
选取了30个实施例合金和3个对比例合金，实施例合金均采用本发明的全流程制备方法分别加工成厚度为0.2mm的带材成品。本发明的综合性能优异的铜合金带材的全流程制备工序为：配料→熔炼→铸造→锯切→加热→热轧→铣面→粗轧→固溶与淬火处理→中轧→一级时 效→清洗→预精轧→二级时效→清洗→精轧→拉弯矫直，具体包括以下步骤：
1)配料与熔铸：按照合金的化学组成进行原材料准备及配料，采用感应炉进行熔炼，合金的加入顺序为：先加入Cu，熔化后加入Ni、Co，Ni与Co熔化后再加入Ag与CuSi中间合金，选择性添加Mg、Ce、Cr、Zr、Ti、Fe、Mn、Zn、Sn中的一种或多种元素，成分符合要求且经充分除气、除渣后进行铸造，熔炼温度为1270℃，铸造温度为1220℃。
2)锯切：对铸锭进行锯切，去除铸锭的头部与尾部。
3)热轧：在1010℃对铸锭进行加热，并保温3h后进行热轧开坯，900℃之前的总加工率为60％～90％、900℃至840℃之间总加工率为30％～60％的热轧方式进行热轧加工。
4)粗轧：对热轧带材铣面后进行粗轧加工，粗轧加工的总加工率为80％以上。
5)固溶与淬火处理：粗轧后对带材进行固溶淬火处理，固溶温度为950℃～1040℃，保温0.5h，然后进行淬火处理。固溶升温速度为120℃/s，冷却速度为150℃/s。
6)中轧：将固溶并淬火处理后的带材进行中轧加工，中轧加工率在40％。
7)一级时效：对中轧加工后的带材进行一级时效处理，时效温度在400℃～500℃之间，时效时间为6h。
8)预精轧：对一级时效处理后的带材进行预精轧加工，加工率为30％。
9)二级时效：对预精轧加工后的带材进行二级时效处理，时效温度在300℃～400℃范围内，时效时间为3h。
10)精轧：对二级时效处理后的带材进行精轧加工，加工率为5％～20％。
11)拉弯矫直：对精轧加工后的带材进行拉弯矫直，提高带材的板形，得到综合性能优异的铜合金带材成品。
对实施例带材成品进行室温拉伸力学性能、导电率、织构类型及面积占比、Badway 90°折弯检测；并与对比例合金的性能进行对比。
室温拉伸试验按照《GB/T 228.1-2010 金属材料 拉伸试验 第1部分：室温试验方法》在电子万能力学性能试验机上进行，对实施例和对比例均采用厚度为0.2mm的带材试样，拉伸速度为5mm/min。
采用《GB/T 32791-2016铜及铜合金导电率涡流测试方法》测试实施例与对比例带材的导电率。
采用《JCBA T307-2007 Test method of bend formability for sheets and strips of copper and copper alloys》检测实施例与对比例带材的折弯性能(以Badway 90°R/t≤2.5折弯是否开裂进行评价),测试带材的宽度为10mm。
采用EBSD分析实施例和对比例带材的织构类型及面积占比，所谓的各取向的面积占比是指，各取向偏离角度15°以内的面积除以测定面积的比值。
实施例、对比例的成分、具体的形变热处理工艺及织构与性能的检测结果见表1、表2与表3。
表1实施例与对比例的成分
Figure PCTCN2020116375-appb-000001
续表1
Figure PCTCN2020116375-appb-000002
Figure PCTCN2020116375-appb-000003
Figure PCTCN2020116375-appb-000004
Figure PCTCN2020116375-appb-000005
Figure PCTCN2020116375-appb-000006
Figure PCTCN2020116375-appb-000007
Figure PCTCN2020116375-appb-000008
虽然对比例1 C70250合金带材的Badway 90°折弯R/t≤2.5也不开裂，但C70250合金带材的屈服强度只有650.2MPa，低于本发明的合金带材的屈服强度。
对于两个C70350合金带材的对比例，当屈服强度比较低时(832.7MPa)，其Badway 90°折弯R/t≤2.5也不开裂，但当屈服强度与本发明的带材的屈服强度相当时(868.2MPa)，其Badway 90°折弯R/t≤2.5出现了开裂。

Claims (10)

  1. 一种综合性能优异的铜合金带材，其特征在于该铜合金的重量百分比组成包括：Ni：2.5wt％～4.0wt％，Co：0.2wt％～1.2wt％，Si：0.4wt％～1.4wt％，Ag：0.01wt％～0.2wt％，余量为Cu。
  2. 根据权利要求1所述的综合性能优异的铜合金带材，其特征在于，该铜合金带材的织构类型及其面积占比如下：立方织构的面积占比为10％～30％、黄铜织构的面积占比为5％～20％、铜型织构的面积占比为5％～20％、余量为其他类型的织构，织构面积占比为各取向偏离角度15°以内的面积除以测定面积的比值。
  3. 根据权利要求2所述的综合性能优异的铜合金带材，其特征在于，该铜合金带材的立方织构与黄铜织构、铜型织构的面积占比满足：0.3≤a/(b+c)≤2.0，其中a为立方织构的面积占比，b为黄铜织构的面积占比，c为铜型织构的面积占比。
  4. 根据权利要求1所述的综合性能优异的铜合金带材，其特征在于，该铜合金带材还包括可选元素中的至少一种，可选元素重量百分比组成总计0.5wt％以下；可选元素为Mg：0.001wt％～0.2wt％、Ce：0.001wt％～0.2wt％、Cr：0.001wt％～0.1wt％、Zr：0.001wt％～0.1wt％、Ti：0.001wt％～0.1wt％、Fe：0.001wt％～0.2wt％、Mn：0.001wt％～0.2wt％、Zn：0.001wt％～0.2wt％、Sn：0.001wt％～0.2wt％。
  5. 根据权利要求1至4中任一权利要求所述的综合性能优异的铜合金带材，其特征在于，该铜合金带材的屈服强度为850MPa以上、弹性模量为120GPa以上、导电率为45％IACS以上、Badway 90°折弯R/t≤2.5。
  6. 根据权利要求1至4中任一权利要求所述的综合性能优异的铜合金带材的制备方法，制备流程如下：配料→熔炼→铸造→锯切→加热→热轧→铣面→粗轧→固溶与淬火处理→中轧→一级时效→清洗→预精轧→二级时效→清洗→精轧→拉弯矫直；其特征在于，所述热轧的总加工率在90％以上且终轧温度控制在840℃以上，900℃以上热轧为第一段热轧加工，轧制率为60％～90％；900℃至终轧温度840℃之间为第二段热轧加工，轧制率为第一段热轧加工后板坯厚度的30％～60％；所述热轧加工后带材中的铜型织构面积占比在40％以上。
  7. 根据权利要求6所述的综合性能优异的铜合金带材的制备方法，其特征在于，所述粗轧的总加工率控制在80％以上。
  8. 根据权利要求6所述的综合性能优异的铜合金带材的制备方法，其特征在于，所述固溶淬火温度控制在950℃～1040℃，保温时间为0.1h～1h，固溶升温速度须在100℃/s以上，淬火冷却速度在150℃/s以上，所述固溶后带材中立方织构的面积占比在35％以上。
  9. 根据权利要求6所述的综合性能优异的铜合金带材的制备方法，其特征在于，所述中轧的加工率控制在20％～65％；所述一级时效后预精轧的加工率控制在10％～40％，二级时效后精轧的加工率控制在5％～20％。
  10. 根据权利要求6所述的综合性能优异的铜合金带材的制备方法，其特征在于，所述一 级时效温度为400℃～500℃，保温时间为5h～8h；二级时效温度在300℃～400℃范围内，保温时间为2h～5h。
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115109964A (zh) * 2022-07-06 2022-09-27 昆明冶金研究院有限公司北京分公司 高强导电抗高温软化Cu-Ni-Si系合金及制备方法
CN115896534A (zh) * 2022-11-29 2023-04-04 宁波博威合金板带有限公司 一种含铬铜合金带材及其制备方法和应用
CN116136005A (zh) * 2023-02-24 2023-05-19 宁波金田铜业(集团)股份有限公司 一种铜合金带材及其制备方法和应用
CN118147484A (zh) * 2024-01-05 2024-06-07 宁波兴业盛泰集团有限公司 平衡性能型铜合金材料及其制备方法

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111485132B (zh) * 2020-04-10 2021-09-10 宁波博威合金板带有限公司 一种综合性能优异的铜合金带材及其制备方法
CN112501472B (zh) * 2020-11-26 2022-03-11 宁波博威合金板带有限公司 一种高性能铜合金带材及其制备方法
CN113106291B (zh) * 2021-03-23 2022-04-26 宁波金田铜业(集团)股份有限公司 一种综合性能优异的锡磷青铜带材及其制备方法
CN115125413B (zh) * 2022-06-30 2023-08-01 宁波金田铜业(集团)股份有限公司 一种综合性能优异的铜合金带材及其制备方法
CN115386767B (zh) * 2022-08-17 2023-08-08 宁波博威合金板带有限公司 一种超大规模集成电路芯片封装用引线框架铜合金带材及其制备方法
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101146920A (zh) * 2005-03-24 2008-03-19 日矿金属株式会社 电子材料用铜合金
CN101270423A (zh) * 2007-03-19 2008-09-24 日矿金属加工株式会社 电子材料用Cu-Ni-Si系铜合金
CN102560191A (zh) * 2010-12-09 2012-07-11 北京有色金属研究总院 一种高性能弹性铜合金及其制备和加工方法
US20140116583A1 (en) * 2012-10-31 2014-05-01 Dowa Metaltech Co., Ltd. Cu-Ni-Co-Si BASED COPPER ALLOY SHEET MATERIAL AND METHOD FOR PRODUCING THE SAME
CN106636734A (zh) * 2015-10-30 2017-05-10 北京有色金属研究总院 高强度、高导电、高抗应力松弛铜合金弹性材料及其制备方法
CN108193080A (zh) * 2016-12-08 2018-06-22 北京有色金属研究总院 高强度、高导电耐应力松弛铜镍硅合金材料及其制备方法
CN111485132A (zh) * 2020-04-10 2020-08-04 宁波博威合金板带有限公司 一种综合性能优异的铜合金带材及其制备方法

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP5539932B2 (ja) * 2011-08-01 2014-07-02 Ｊｘ日鉱日石金属株式会社 曲げ加工性に優れたＣｕ−Ｃｏ−Ｓｉ系合金
JP5117604B1 (ja) * 2011-08-29 2013-01-16 Ｊｘ日鉱日石金属株式会社 Ｃｕ−Ｎｉ−Ｓｉ系合金及びその製造方法
WO2015146981A1 (ja) * 2014-03-25 2015-10-01 古河電気工業株式会社 銅合金板材、コネクタ、および銅合金板材の製造方法
JP6385382B2 (ja) * 2016-03-31 2018-09-05 Ｊｘ金属株式会社 銅合金板材および銅合金板材の製造方法
JP6385383B2 (ja) * 2016-03-31 2018-09-05 Ｊｘ金属株式会社 銅合金板材および銅合金板材の製造方法
CN109609801A (zh) * 2018-12-06 2019-04-12 宁波博威合金材料股份有限公司 高性能铜合金及其制备方法
CN110835699B (zh) * 2019-11-05 2020-12-22 宁波兴业盛泰集团有限公司 一种高强高导铜铬锆系合金材料及其制备方法

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101146920A (zh) * 2005-03-24 2008-03-19 日矿金属株式会社 电子材料用铜合金
CN101270423A (zh) * 2007-03-19 2008-09-24 日矿金属加工株式会社 电子材料用Cu-Ni-Si系铜合金
CN102560191A (zh) * 2010-12-09 2012-07-11 北京有色金属研究总院 一种高性能弹性铜合金及其制备和加工方法
US20140116583A1 (en) * 2012-10-31 2014-05-01 Dowa Metaltech Co., Ltd. Cu-Ni-Co-Si BASED COPPER ALLOY SHEET MATERIAL AND METHOD FOR PRODUCING THE SAME
CN106636734A (zh) * 2015-10-30 2017-05-10 北京有色金属研究总院 高强度、高导电、高抗应力松弛铜合金弹性材料及其制备方法
CN108193080A (zh) * 2016-12-08 2018-06-22 北京有色金属研究总院 高强度、高导电耐应力松弛铜镍硅合金材料及其制备方法
CN111485132A (zh) * 2020-04-10 2020-08-04 宁波博威合金板带有限公司 一种综合性能优异的铜合金带材及其制备方法

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115109964A (zh) * 2022-07-06 2022-09-27 昆明冶金研究院有限公司北京分公司 高强导电抗高温软化Cu-Ni-Si系合金及制备方法
CN115109964B (zh) * 2022-07-06 2024-01-05 中铝科学技术研究院有限公司 高强导电抗高温软化Cu-Ni-Si系合金及制备方法
CN115896534A (zh) * 2022-11-29 2023-04-04 宁波博威合金板带有限公司 一种含铬铜合金带材及其制备方法和应用
CN116136005A (zh) * 2023-02-24 2023-05-19 宁波金田铜业(集团)股份有限公司 一种铜合金带材及其制备方法和应用
CN118147484A (zh) * 2024-01-05 2024-06-07 宁波兴业盛泰集团有限公司 平衡性能型铜合金材料及其制备方法

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