WO2020113352A1

WO2020113352A1 - High-performance copper alloy and preparation method therefor

Info

Publication number: WO2020113352A1
Application number: PCT/CN2018/000424
Authority: WO
Inventors: 杨泰胜; 周银银; 李建刚; 杨朝勇; 周耀华
Original assignee: 宁波博威合金材料股份有限公司; 宁波博威合金板带有限公司
Priority date: 2018-12-06
Filing date: 2018-12-18
Publication date: 2020-06-11
Also published as: CN109609801A

Abstract

A high-performance copper alloy and a preparation method therefor. The weight percentage composition of the copper alloy is: Sn: 0.05 wt% to 3.0 wt%, Ni: 0.01 wt% to 2.5 wt%, Si: 0.01 wt% to 0.6 wt%, and Zn: 5 wt% to 15 wt%, the weight percentage ratio of Ni to Si satisfying Ni/Si = 3.0 - 6.0, and the balance being Cu and inevitable impurities. The preparation process for a strip of the copper alloy comprises: dosing, melting, hot rolling, milling, primary cold rolling, primary aging, secondary cold rolling, secondary aging, cold rolling before forming, and low-temperature annealing. Said copper alloy uses Cu and Zn as the matrix, and the performance of the alloy is improved by adding elements such as Sn, Ni, and S. At the same time, the microstructure such as the grain size and crystal orientation of the alloy is further adjusted to achieve balance of the conductivity, strength and bending processing performance, thereby meeting application needs of middle-end and high-end electronic and electrical components.

Description

High-performance copper alloy and preparation method thereof

Technical field

The invention relates to the technical field of copper alloys, in particular to a high-performance copper alloy and a preparation method thereof.

Background technique

Copper alloy materials for electrical and electronic components such as connectors, frame materials, relays, and switches are required to have good electrical conductivity in order to reduce the heat generated when electricity is applied. At the same time, in order to ensure that the electronic and electrical components do not undergo plastic deformation during work and assembly, the copper alloy material is required to have sufficiently high strength. In addition, electronic and electrical components are mainly formed by bending, therefore, the copper alloy materials used are required to have good bending performance.

In recent years, with the rapid development of industries such as communications and automobiles, higher requirements have been placed on the electrical conductivity of electronic and electrical components. The better the conductivity, the faster the electronic signal transmission rate, and the better the heat dissipation performance. Middle and high-end connectors usually need to meet the conductivity requirements of 25% IACS or more. The intensive and lightweight structure of electronic and electrical components requires the copper alloy strip used to become thinner and thinner, which requires the material to have higher strength. Specifically, the yield strength of the material needs to reach more than 550MPa. At the same time, the miniaturization of electronic and electrical components and the complication of shapes have increasingly higher requirements on the shape and dimensional accuracy of materials after bending. Generally, when the thickness of the strip is less than 0.3mm, the R/t in the BD direction ≤2.

Generally, there is a long-term and negative relationship between the strength of the alloy and the electrical conductivity and bending performance. It is technically difficult to improve these properties at the same time. Therefore, when selecting copper alloy materials for electronic and electrical components, different types of copper alloys are often selected according to specific uses.

Cu-Ni-Si series alloys (so-called Corson alloys) are widely used in high-end connectors due to their good electrical conductivity (conductivity: 30-45% IACS) and strength balance, but their cost is relatively high. Moreover, it is difficult to realize the balance between strength and bending performance, which restricts its application to a certain extent.

Tin-phosphor bronze is a widely used copper alloy in connectors, terminals and other fields. Since Sn in tin-phosphor bronze is mainly present in the copper matrix in the form of solid solution, tin-phosphor bronze with high Sn content has higher strength and higher conductivity Poor, it is difficult to achieve a good match between strength and conductivity, such as C52100, C51900, the yield strength is above 550MPa, and the conductivity is less than 20% IACS, can not meet the high-end connectors, terminals and other electronic and electrical components on the strength and Conductivity requirements.

Summary of the invention

The technical problem to be solved by the present invention is to provide a high-performance copper alloy with excellent comprehensive performance and a preparation method thereof for the problem that traditional copper alloys are difficult to achieve good matching of electrical conductivity, yield strength, and bending processing performance, and to meet the needs of high-end electronic and electrical Application requirements of components.

The technical solutions adopted by the present invention to solve the above technical problems are: high-performance copper alloy, the weight percentage composition of the copper alloy is: Sn: 0.05wt% ~ 3.0wt%, Ni: 0.01wt% ~ 2.5wt%, Si: 0.01 wt% ~ 0.6wt%, Zn: 5wt% ~ 15wt%, and the weight percentage ratio of Ni and Si satisfies: Ni/Si = 3.0 ~ 6.0, the balance is Cu and inevitable impurities.

In the present invention, Cu and Zn are used as the matrix, and the performance of the alloy is improved by adding elements such as Sn, Ni and Si. Elements such as Sn and Zn mainly enhance the strength of the alloy by solid solution strengthening. At the same time, the present invention achieves strengthening by forming a NiSi phase with Ni and Si, and further improves the strength of the alloy without significantly reducing the electrical conductivity of the alloy. In addition to the solid solution strengthening and cost-saving effects, the Zn element added to the alloy of the present invention gives the alloy obvious advantages in welding, electroplating, etc.

The effect of adding Sn to the copper alloy of the present invention is to improve the strength and elasticity of the alloy, and at the same time improve the stress relaxation resistance (heat resistance) of the alloy at about 150°C. Sn is a beneficial additive element for copper alloy materials for electronic and electrical components. However, when the Sn content is less than 0.05wt%, its effect on improving alloy performance is not ideal. When the Sn content exceeds 3.0wt%, the conductivity of the alloy will be greatly reduced. Therefore, the present invention controls the Sn content to 0.05wt% ~ 3.0wt %.

Adding a certain amount of Ni to the copper alloy matrix can play the role of solid solution strengthening, but the more important role of Ni in the copper alloy of the present invention is to form a NiSi phase with Si, which does not significantly reduce its conductivity while improving the strength of the alloy . If the Ni content is less than 0.01wt%, the improvement of the alloy strength is not obvious; when the Ni content exceeds 2.5wt%, the probability of incomplete precipitation of NiSi phase increases, which will reduce the conductivity of the alloy and apply cold deformation after the alloy is aged During strengthening, the high content of NiSi is unfavorable for the bending performance of the copper alloy strip. Therefore, the present invention controls the Ni content to 0.01 wt% to 2.5 wt%.

The role of adding Si in the present invention is to form a NiSi phase with Ni to improve the strength of the alloy. Too much Si will significantly reduce the conductivity of the alloy. Therefore, the present invention controls the Si content to 0.01wt% ~ 0.6wt%, so that Si exists as much as possible in the form of NiSi phase.

The Zn element is added to the copper alloy of the present invention. On the one hand, Zn has a solid solution strengthening effect, which can improve the strength of the substrate. On the other hand, Zn also has a significant effect on improving the solder wettability and tin plating adhesion of the alloy. In addition, compared with other elements, the price of Zn is lower, and cheap brass scrap can be used as the source of Zn in the copper alloy of the present invention. If the content of Zn is too low, the solid solution strengthening effect is not obvious, and the recycling rate of copper alloy to brass scrap is reduced, which increases the raw material cost. If the Zn content is too high, it will reduce the electrical conductivity, bending performance and stress corrosion resistance of the alloy. Therefore, the present invention controls the Zn content to 5 wt% to 15 wt%.

In addition to controlling the added elements and their contents, the present invention also realizes the further improvement of the alloy's comprehensive properties including electrical conductivity, yield strength, bending processability and other properties by optimizing the alloy's grain size, crystal orientation and other microstructures balanced.

The average grain size of the copper alloy strip of the invention after aging is ≤15 μm. The smaller the grain diameter is, the more beneficial it is to increase the strength of the alloy, and the more favorable it is to improve the bending performance of the alloy. However, the crystal grains are too coarse, the number of grain boundaries decreases, the effect of strengthening grain boundaries is weakened, and the surface of the copper alloy strip bending part is rough, which reduces the bending performance. According to the results of repeated experiments and verification by the inventors of the present application, the average grain size of the copper alloy strip of the present invention after aging is controlled to be ≤15 m, which can ensure the balance between alloy strength and bending workability.

The copper alloy texture meets within a deviation angle of less than 20°:

The area ratio of Goss{011}<100>+Brass{011}<211>+S{123}<634> is 20%-60%, and Cube{100}<001>+{120}<001>+{ 113} The area ratio of <121> is 15% or more. The Schmid factor is an index that characterizes the difficulty of crystal deformation. The larger the value, the easier the crystal is to deform. Conversely, the greater the resistance to deformation of the crystal. The Schmid factor of the grain with deformation texture is smaller than that of the grain with recrystallization texture. Therefore, when the area ratio of the deformation texture in the alloy material gradually increases, the overall Schmid factor will gradually decrease, which eventually causes the deformation of the grain The difficulty gradually increases, the work hardening of the material increases, and the bending process of the alloy strip gradually becomes difficult. When the area ratio of the deformation texture reaches a certain value, the alloy strip is prone to cracking during bending, so the area ratio of the deformation texture needs to be controlled within a certain range. As the amount of cold rolling deformation increases, the area ratio of the Goss{011}<100>, Brass{011}<211>, S{123}<634> textures of the copper alloy strip of the invention gradually increases (orientation density Value increases), the intensity increases accordingly. After cold rolling deformation, the annealing treatment is carried out. The area ratio of Cube{100}<001>,{120}<001>,{113}<121> texture increases, the area ratio of deformation texture decreases, and the material can get better. The plasticity and bending performance. The research results of the inventors of the present application indicate that to achieve the yield strength of the alloy strip above 550 MPa, the copper alloy texture is within a deviation angle of less than 20°, Goss{011}<100>+Brass{011}<211>+S{ 123} The area ratio of <634> needs to be controlled at more than 20%; in order to take into account the bending performance of the alloy strip (90° bending performance: the value in the GW direction is R/t≤1, the value in the BW direction is R/t≤ 2), the area ratio of Goss{011}<100>+Brass{011}<211>+S{123}<634> needs to be controlled below 60%, and it is particularly important that Cube{100}<001>+ The area ratio of {120}<001>+{113}<121> shall be controlled above 15%.

In the microstructure of the copper alloy of the present invention, the volume fraction of 15°-180° grain boundaries is ≥40%. In polycrystalline materials, the grain boundaries with adjacent grain orientation differences greater than 10° are called high-angle grain boundaries, and the grain boundaries with less than 10° orientation difference are called small-angle grain boundaries. Large-angle grain boundaries can make crack propagation difficult, thereby increasing the material's tendency to bend and deform. The small-angle grain boundary is composed of a series of dislocations. The degree of dislocation plugging is high, and cracks are easy to propagate, so that the material is prone to cracking in bending deformation. When the material is in the aging state, the proportion of large-angle grain boundaries is greater than 80%, and the material has excellent bending workability. After cold deformation, the number of high-angle grain boundaries gradually decreases, and the small-angle grain boundaries gradually increase, that is, the degree of dislocation plugging of the material increases, so that the strength of the alloy material increases and the bending performance decreases. In order to obtain a balance between bending workability and strength, the present invention controls the volume fraction of 15°～180° grain boundaries in the microstructure to be ≥40%, so as to realize the bending performance of the alloy strip in the BW direction R/t≤2, and the yield strength ≥550MPa .

The weight percentage composition of the copper alloy of the present invention further contains 0.01 wt% to 2.5 wt% Co. Co and Si are added at the same time to form CoSi intermetallic compounds. Through the solution aging process, the CoSi phase is dispersed on the substrate, which further improves the strength of the alloy without significantly reducing the conductivity. When the Co content exceeds 2.5 wt%, the probability of incomplete precipitation of the CoSi phase increases, which reduces the electrical conductivity of the alloy. When the Co content is less than 0.01 wt%, a sufficient number of precipitated phases cannot be formed to improve the performance of the material. Therefore, the present invention controls the Co content to 0.01 wt% to 2.5 wt%.

The weight percentage composition of the copper alloy of the present invention further contains 0.01 wt% to 2.0 wt% Fe and/or 0.01 wt% to 0.5 wt% P. The role of Fe is to refine the alloy grains. A small amount of Fe can improve the strength of the alloy, but too much Fe content will reduce the electrical conductivity of the alloy. When Fe and P are added at the same time, FeP compounds can be formed, and the dispersed distribution of FeP compounds can enhance the strength of the material to a certain extent without significantly reducing its conductivity. Therefore, in the present invention, the content of Fe is controlled at 0.01 wt% to 2.0 wt%. P can effectively deoxidize, increase the fluidity of the alloy melt, and further improve the strength, hardness, elastic modulus, fatigue strength and wear resistance of the alloy. However, if P is excessive, the electrical conductivity of the alloy will be seriously reduced, and the Cu3P low-melting eutectic phase will be easily formed, which will easily cause hot rolling cracking of the alloy. Therefore, in the present invention, the content of P is controlled at 0.01 wt% to 0.5 wt%.

The weight percent composition of the copper alloy of the present invention further contains Mg selected from 0.01 wt% to 0.5 wt%, Cr from 0.01 wt% to 1.5 wt%, 0.01 wt% to 0.3 wt% in a total amount of 0.0001 wt% to 2 wt% Zr, 0.001wt% to 1.5wt% Mn, 0.0005wt% to 0.3wt% B, 0.01wt% to 0.3wt% Ag, 0.01wt% to 1.0wt% Al and 0.0001wt% to 0.1wt% At least one element in the RE.

Mg, B, RE can inhibit the grain boundary reaction, reduce the number of nickel silicon, cobalt and silicon precipitated phases distributed on the grain boundary, reduce the hardness of the alloy after solution treatment, and improve the performance of the cold working. B can also improve the alloy's resistance to dezincification and improve corrosion resistance. B. Mg can also improve the stress relaxation resistance of the alloy and improve the hot and cold workability of the alloy. RE can remove impurities and oxygen during smelting, improve the purity of metals, and has a high melting point of rare earth. It can be used as the core of crystallization during smelting, reducing the content of columnar crystals in the ingot and increasing the content of equiaxed crystals, thereby improving the material Hot workability.

Cr can increase the softening temperature and high temperature strength of the alloy, improve the high temperature stability of the alloy, and reduce its stress relaxation rate.

Mn can play a deoxidizing role in the smelting process, improve the purity of the alloy, can also improve the hot working performance of the alloy, and improve the basic mechanical properties of the alloy.

Al can increase the strength and hardness of the alloy through solid solution strengthening. In addition, Al can form a NiAl intermetallic compound with Ni in the alloy to increase the strength. In addition, the tendency of Al ionization is greater than that of Zn, and it can preferentially react with corrosive gases and oxygen in the solution to form a protective film to improve the corrosion resistance of the alloy material.

Zr has an aging strengthening effect, and the strength is improved by forming Cu ₅ Zr and Cu ₃ Zr, and the addition of Zr can significantly increase the recrystallization temperature of the alloy, thereby improving the high temperature softening resistance of the alloy.

Ag has the function of solid solution strengthening and can improve the strength and hardness of the alloy. Generally, when the trace elements are solid-dissolved in the matrix, lattice distortion of the matrix will occur, and then the scattering effect on the moving electrons will increase, and the alloy will show the characteristics of increased strength and reduced conductivity. Different from other elements, when a small amount of Ag is solid-dissolved in the matrix, the strength and hardness of the alloy increase, and the electrical and thermal conductivity performance does not decrease significantly. In addition, Ag can increase the recrystallization temperature of the alloy.

The copper alloy of the present invention can be processed into plates, strips, rods, wires, etc. according to different application requirements. It is used in the electrical and electronic industry. Taking the (plate) strip as an example, its preparation process is: batching → melting → hot rolling →milled surface→primary cold rolling→primary aging→secondary cold rolling→secondary aging→pre-completion cold rolling→low temperature annealing→cleaning→striping→packaging, in which:

The melting temperature is 1080℃～1280℃, and the melting casting method is semi-continuous casting or horizontal continuous casting.

Hot rolling: The hot rolling temperature of the alloy is controlled at 750℃～900℃, and the holding time is 1h～6h. In order to ensure that the coarse precipitated phases in the ingot are redissolved, the hot rolling temperature of the alloy is controlled at 750℃～900℃, and the holding time is controlled at 1h～6h. Under this process, the alloy can achieve the purpose of homogenizing the composition. In order to minimize the precipitation of phase particles after hot rolling, the final rolling temperature of the alloy is controlled above 600°C, and online water cooling after hot rolling. The rolling reduction rate should be controlled above 85%.

Milled surface: the milled surface of the hot-rolled plate is 0.5mm～1.0mm to remove the scale on the surface.

Primary cold rolling: The total rolling reduction of cold rolling is controlled above 80%. A cold rolling rate of more than 80% allows the material to have sufficient storage energy to ensure the formation of an ideal recrystallized structure after annealing, which is beneficial to increase the content of recrystallized texture.

One aging: the temperature is 350℃～550℃, and the aging time is 5h～10h. The main purpose of primary aging is to achieve the softening of the material. In this process, there is aging precipitation of the NiSi phase. For the production of thin strips, the aging temperature is preferably 350 ℃ ~ 550 ℃, to ensure that the material is under aging, to avoid the later aging process, The material has over-aging; for the production of thick belts, the aging temperature is controlled at 450 ℃ ~ 550 ℃, increase the precipitation strengthening effect of NiSi phase in one aging process, the aging time is preferably 5h ~ 10h.

Secondary cold rolling: The rolling rate is controlled at 60% to 85%. Controlling the rolling rate of secondary cold rolling at 60% to 85% is conducive to the precipitation of NiSi phase and can significantly improve the strength of the alloy. If the amount of deformation is too small, it is not conducive to the completion of recrystallization of the aging structure in the later period, reducing the uniformity of the grain size, which is unfavorable for the bending process of the plate and strip.

Secondary aging: temperature is 300℃～500℃, aging time is 5h～10h. When the temperature of the secondary aging is higher than 500℃, the alloy strip structure is completely recrystallized, the area ratio of the texture of Cube{100}<001>, {120}<001>, {113}<121> increases, and the large angle The increase of the volume of the grain boundary is beneficial to the improvement of the bending performance of the finished strip, but at this time, the diffusion rate of atoms is faster, the alloy strip is prone to over-aging, the NiSi phase is roughened, and the mechanical properties of the sheet strip are reduced. The bonding surface of the modified NiSi phase and the substrate is weak, and cracks easily germinate at the bonding surface during severe bending deformation, resulting in a decrease in bending performance. When the aging temperature is less than 300℃, the alloy strip retains more deformation structure after aging, and the area ratio of Goss{011}<100>, Brass{011}<211>, S{123}<634> texture is high The volume content of the large-angle grain boundary is reduced, which is detrimental to the bending performance of the finished strip and is not conducive to the aging precipitation of the NiSi phase. Therefore, the secondary aging temperature of the alloy of the present invention is controlled at 300 ℃ ~ 500 ℃, the aging time is controlled at 5h～10h.

Cold rolling before completion: The rolling rate is controlled below 50%. Applying cold deformation to the alloy after the second aging is conducive to further increase the strength of the strip, but the amount of deformation should not be too large, too large may easily lead to Goss{011}<100>, Brass{011}<211>, S{123} <634> The area ratio of the texture increases and the number of small-angle grain boundaries increases, which is not conducive to the bending workability of the strip.

Low temperature annealing: the temperature is 150℃～300℃, and the aging time is 3h～6h. For copper alloys with high zinc content, low-temperature annealing after cold deformation is beneficial to improve the strength of the material, especially the yield strength, and also release certain residual stress. The low-temperature annealing temperature is controlled at 150℃～300℃ If the temperature is too high, the purpose of strengthening cannot be achieved.

Compared with the prior art, the advantages of the present invention are:

(1) The present invention uses Cu, Zn as a matrix, by adding elements such as Sn, Ni, Si, etc. The elements such as Ni, Sn, Zn are strengthened by solid solution to increase the strength of the alloy, and at the same time, the present invention strengthens the NiSi phase by precipitation of Ni and Si , Further improve the strength of the alloy without significantly reducing the electrical conductivity of the alloy.

(2) In the present invention, the average grain size of the copper alloy strip after aging is controlled to be less than 15 μm, and the texture of the copper alloy is less than 20° Goss{011}<100>+Brass{011}<211 >+S{123}<634> area ratio is controlled at 20%～60%, and Cube{100}<001>+{120}<001>+{113}<121> area ratio is controlled above 15% Through aging, the matrix grain size and crystal orientation further achieve the balance of electrical conductivity, yield strength, and bending processing performance to meet the application needs of high-end electronic and electrical components.

(3) The preparation process of the copper alloy of the invention through aging, cold rolling deformation, low annealing, etc. can achieve a yield strength of 550 MPa or more and a conductivity of 25% to 40% IACS. The 90° bending workability of the copper alloy strip is as follows: the value in the GW direction is R/t≤1, and the value in the BW direction is R/t≤2.

(4) The copper alloy of the present invention can solve the problem of utilization of various wastes, such as: brass scrap, nickel-plated scrap used in connectors such as personal computers and mobile phones, tin-plated scrap used in connectors for automobiles, and automobile-oriented Tin-plated brass scrap, etc., are conducive to energy saving and consumption reduction, reduce the cost of alloy preparation, and promote the recycling of scrap.

(5) The copper alloy of the present invention can be processed into products such as rods, wires, and strips, which are widely used in electrical and electronic industries such as connectors and connectors.

detailed description

The present invention will be further described in detail below with reference to examples.

Twenty example alloys and one comparative alloy (C51900 tin phosphor bronze) were selected, the added elements were added to the melting furnace according to their respective contents, and semi-continuous casting ingots of 170 mm x 320 mm ingots were cast at a casting temperature of 1150°C.

The other main preparation process parameters are:

Hot rolling: heating temperature 820 ℃, heat preservation 5h, hot rolling to 15.5mm;

Face milling: face milling up and down to 14.5mm;

Primary cold rolling: 14.5mm cold rolling to 1.5mm;

One aging: aging temperature 450℃, aging time 8h;

Secondary cold rolling: 1.5mm cold rolling to 0.38mm;

Secondary aging: aging temperature 425℃, aging time 8h;

Cold rolling before forming: 0.38mm cold rolling to 0.3mm;

Low temperature annealing: annealing temperature 210℃, annealing time 6h, to obtain strip samples.

For the prepared strip samples of 20 example alloys and 1 comparative alloy, the mechanical properties, electrical conductivity, stress relaxation resistance and bending properties were tested respectively.

The room temperature tensile test was carried out on the electronic universal performance testing machine in accordance with "GB/T228.1-2010 Metal Material Tensile Test Part 1: Room Temperature Test Method", using a lead sample with a width of 12.5mm and a tensile speed of 5mm /min.

Conductivity test according to "GB/T3048.2-2007 wire and cable electrical performance test method part 2: metal material resistivity test", this testing instrument is ZFD microcomputer bridge DC resistance tester, sample width is 20mm, length is 500mm .

The stress relaxation resistance test is in accordance with "JCBA T309: 2004 Test Method for Bending Stress Relaxation of Copper and Copper Alloy Sheets". The sample is taken parallel to the rolling direction. The sample width is 10 mm and the length is 100 mm. The initial loading stress value is 0.2% of the yield strength of 50 %, the test temperature is 150 ℃, the time is 1000h.

The bending performance test is carried out on the bending test machine according to "GBT 232-2010 Metal Material Bending Test Method". The sample width is 5mm and the length is 50mm.

The composition and performance test results of the alloys of the examples and the comparative examples are shown in Table 1. In Table 1, "Goss+Brass+S" represents the area ratio of Goss{011}<100>+Brass{011}<211>+S{123}<634> of alloy texture in the deviation angle less than 20°, "Cube+{120}<001>+{113}<121>" represents the alloy texture Cube{100}<001>+{120}<001>+{113}<121> within the deviation angle of less than 20° Area ratio.

Claims

The high-performance copper alloy is characterized in that the weight percentage composition of the copper alloy is: Sn: 0.05wt%-3.0wt%, Ni: 0.01wt%-2.5wt%, Si: 0.01wt%-0.6wt%, Zn: 5wt%~15wt%, and the weight percentage ratio of Ni and Si satisfies: Ni/Si=3.0~6.0, the balance is Cu and inevitable impurities.
The high-performance copper alloy according to claim 1, wherein the average grain size of the copper alloy strip after aging is ≤15 μm.
The high-performance copper alloy according to claim 1, wherein the texture of the copper alloy is satisfied within a deviation angle of less than 20°: Goss{011}<100>+Brass{011}<211>+S{123} The area ratio of <634> is 20% to 60%, and the area ratio of Cube{100}<001>+{120}<001>+{113}<121> is 15% or more.
The copper alloy according to claim 1, characterized in that, in the microstructure of the copper alloy, the volume fraction of 15°-180° grain boundaries is ≥ 40%.
The high-performance copper alloy according to claim 1, characterized in that the weight percentage composition of the copper alloy further contains 0.01 wt% to 2.5 wt% Co.
The high-performance copper alloy according to claim 1, characterized in that the weight percentage composition of the copper alloy further contains 0.01 wt% to 2.0 wt% Fe and/or 0.01 wt% to 0.5 wt% P.
The high-performance copper alloy according to claim 1, characterized in that the weight percentage composition of the copper alloy further contains Mg, 0.01wt% selected from 0.01wt% to 0.5wt% in a total amount of 0.0001wt% to 2wt% ～1.5wt% Cr, 0.01wt%～0.3wt% Zr, 0.001wt%～1.5wt% Mn, 0.0005wt%～0.3wt% B, 0.01wt%～0.3wt% Ag, 0.01wt% At least one element of ~1.0 wt% Al and 0.0001 wt% ~ 0.1 wt% RE.
The high-performance copper alloy according to any one of claims 1 to 7, characterized in that the yield strength of the copper alloy is 550 MPa to 700 MPa, the conductivity is 25% IACS to 40% IACS; The 90° bending performance is as follows: the value in the GW direction is R/t≤1, and the value in the BW direction is R/t≤2.
The method for preparing a high-performance copper alloy according to any one of claims 1-7, characterized in that the preparation process of the copper alloy strip is: batching → smelting → hot rolling → milling surface → primary cold rolling → primary Aging→secondary cold rolling→secondary aging→pre-cold rolling→low temperature annealing.
The method for preparing a high-performance copper alloy according to claim 9, characterized in that the temperature of the hot rolling is 750°C to 900°C, and the holding time is 1h to 6h; the temperature of the primary aging is 350°C to 550 ℃, aging time is 5h ~ 10h; the temperature of the second aging is 300 ℃ ~ 500 ℃, aging time is 5h ~ 10h.