High-conductivity copper alloy wire and preparation process thereof

Abstract

The invention relates to the technical field of copper alloy, in particular to a high-conductivity copper alloy wire and a preparation process thereof. The preparation technology of the high-conductivity copper alloy wire comprises the following steps that nano Y2O3 particles and nano CeO2 particles are evenly mixed and mixed into CuCrZr alloy powder, then composite coating carbon fibers are added for ball milling, obtained alloy composite powder is subjected to pressing, sintering, heat treatment, extrusion forming and aging treatment, and the high-conductivity copper alloy wire is obtained. The nano Y2O3 particles and the nano CeO2 particles are used as reinforcement phase particles, multi-scale reinforcement sites can be formed in a copper alloy matrix, fine grain reinforcement is achieved, dislocation motion resistance is increased, and under the condition that good conductivity is maintained, the tensile strength of the high-conductivity copper alloy wire is effectively improved; by adding the composite coating carbon fiber, the bonding strength of the carbon fiber and the copper alloy matrix is improved, the conductivity of the high-conductivity copper alloy wire is improved, and the conductivity and strength of the high-conductivity copper alloy wire are balanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of copper alloy, more particularly, it relates to a high-conductivity copper alloy wire and a preparation process thereof. BACKGROUND

[0002] The copper alloy wire is widely used in the fields of track circuit and electric locomotive due to its high mechanical strength, good conductivity and heat conductivity, and easy pressure processing, and has become the most widely used conductive material at present. With the development of high-tech fields, higher requirements are put forward for the performance of copper alloy, that is, the copper alloy should have both high strength and high conductivity. However, the current design of high-strength and high-conductivity copper alloy has the following problems: any method for improving the strength of the copper alloy will cause the conductivity of the copper alloy to decrease to different degrees. For example, when the strength of the alloy is improved by adding a reinforcing phase, the reinforcing phase may cause the increase of the grain boundary, form more scattering centers, intensify the electron scattering, and thus reduce the conductivity.

[0003] In addition, the carbon fiber itself has good conductivity and heat conductivity, and its density is much lower than that of the copper alloy. Therefore, the carbon fiber is added to the copper alloy to prepare the wire, so that the mechanical properties and lightweight characteristics can be optimized while the conductivity and heat conductivity are maintained or improved. However, the surface of the carbon fiber is smooth and has high chemical inertness, and it is difficult to form chemical bonds or mechanical engagement between the carbon fiber and the copper alloy matrix, which leads to weak interfacial bonding force and easy debonding of the interface, and thus physical gaps are easily formed between the carbon fiber and the copper alloy matrix, the interfacial contact resistance between the carbon fiber and the copper alloy matrix is increased, defects are generated in the copper alloy wire, the overall conductivity of the copper alloy wire is reduced, and the mechanical properties are also affected. SUMMARY

[0004] In view of the deficiencies of the prior art, the present application provides a high-conductivity copper alloy wire and a preparation process thereof.

[0005] The preparation process of the high-conductivity copper alloy wire comprises the following steps: The nano Y2O3 particles and the nano CeO2 particles are uniformly mixed, and then the obtained mixed powder is added to anhydrous ethanol. Under the protection of argon, CuCrZr alloy powder is added, and then stirring, vacuum drying and grinding and screening are performed to obtain a pre-composite powder; The pre-composite powder and the composite plated carbon fiber are put into a ball mill tank for ball milling, wherein the addition amount of the composite plated carbon fiber is 0.8-2.4% of the weight of the pre-composite powder, and an alloy composite powder is obtained; After the alloy composite powder is subjected to pressing, sintering, heat treatment, extrusion molding and aging treatment, a high-conductivity copper alloy wire is obtained. The composite plated carbon fiber is a carbon fiber on the surface of which a nickel layer and a copper layer are sequentially plated.

[0006] Further, the preparation of the CuCrZr alloy powder comprises the following steps: The copper powder, chromium powder and zirconium powder are put into a ball mill tank, stainless steel balls are added under argon protection at a ball-to-charge weight ratio of (10-15):1, and high-energy ball milling is performed at a rotation speed of 200-400 rpm for 24-40 h to obtain the CuCrZr alloy powder.

[0007] Further, the composition of the CuCrZr alloy powder comprises: The chromium powder is 0.6-0.8 wt%, the zirconium powder is 0.1-0.3 wt%, and the balance is copper powder. The copper powder, chromium powder and zirconium powder are all spherical particles.

[0008] Further, the specific preparation steps of the pre-composite powder comprise: The nano Y2O3 particles and nano CeO2 particles are stirred and mixed according to a weight ratio of 1:(0.5-1.5), and the mixed powder is obtained after uniform mixing; 0.5-3 parts by weight of the mixed powder are added to 200-300 parts by weight of anhydrous ethanol, ultrasonic dispersion is performed for 10-30 min to obtain a mixed powder suspension, 100-150 parts by weight of the CuCrZr alloy powder is slowly added to the mixed powder suspension under argon protection, and continuous stirring is performed for 1-3 h to allow the CuCrZr alloy powder to be fully infiltrated in the mixed powder suspension, thereby obtaining a mixed slurry; The mixed slurry is placed in a vacuum drying oven and dried at 70-90°C for 2-4 h, and then ground and sieved to obtain the pre-composite powder.

[0009] Further, the specific preparation steps of the alloy composite powder comprise: The pre-composite powder and the composite plated carbon fiber are put into a ball mill tank, the composite plated carbon fiber is added in an amount of 0.8-2.4% by weight of the pre-composite powder, stainless steel balls are added under argon protection at a ball-to-charge weight ratio of (10-15):1, and high-energy ball milling is performed at a rotation speed of 200-400 rpm for 6-12 h to obtain the alloy composite powder.

[0010] Further, the specific preparation steps of the composite plated carbon fiber comprise: After the carbon fiber is subjected to roughening, sensitization and activation treatment, a pretreated carbon fiber is obtained, the pretreated carbon fiber is added to a plating solution for sufficient infiltration, and then placed in a water bath at 75-90°C for continuous stirring for 30-60 min, followed by suction filtration and drying to obtain a nickel-plated carbon fiber. The DC stabilized power supply is adopted, the nickel-plated carbon fiber is used as the cathode, the high-purity copper plate is used as the anode, the nickel-plated carbon fiber and the high-purity copper plate are placed into the electroplating solution, the current density is controlled to be 0.5-1.5 A / dm2, the temperature is controlled to be 20-30 DEG C, the electroplating time is controlled to be 60-90 min, and after the electroplating is completed, the water washing and drying are carried out, so that the composite plated carbon fiber is obtained.

[0011] Further, the plating solution uses deionized water as a solvent, and comprises the following components: 20-30 g / L of nickel sulfate, 25-35 g / L of sodium hypophosphite, 10-20 g / L of ammonium chloride, 10-20 g / L of sodium citrate, and the pH value of the plating solution is 3-5; the electroplating solution comprises the following components: 40-60 g / L of copper sulfate, 80-120 g / L of potassium citrate, 0.3-0.4 g / L of OP-10 emulsifier, and 10-15 g / L of potassium nitrate.

[0012] Further, the specific preparation steps of the high-conductivity copper alloy wire include: The alloy composite powder is placed into a mold for pressing, the pressing pressure is 100-200 MPa, the alloy composite blank is obtained, the alloy composite blank is placed into a sintering furnace for sintering, the temperature is raised to 920-1000 DEG C at a temperature raising rate of 5-10 DEG C / min under the protection of argon, the pressure is 100-300 MPa, the temperature is kept for 1-2 h, and after the temperature keeping is finished, the furnace is cooled down, and the alloy composite block is obtained; The alloy composite block is placed into a heat treatment furnace and heated to 800-900 DEG C, then is quickly moved into a hydraulic machine for extrusion forming, after the extrusion forming, the temperature is kept for 2-4 h at 450-550 DEG C, and after the temperature keeping is finished, the temperature is air-cooled to room temperature, and the high-conductivity copper alloy wire is obtained.

[0013] Further, the extrusion ratio of the extrusion forming is 20-40.

[0014] A high-conductivity copper alloy wire is prepared by the preparation process of the high-conductivity copper alloy wire.

[0015] The present application has the following advantages: 1. In this invention, by incorporating reinforcing phase particles—nano-Y2O3 particles and nano-CeO2 particles—into CuCrZr powder, the lattice constants of these two highly thermally stable nanoparticles, nano-Y2O3 particles and nano-CeO2 particles, exhibit a moderate mismatch with the copper alloy matrix. This allows the nano-Y2O3 particles and nano-CeO2 particles to not only act as heterogeneous nucleation sites, forming multi-scale strengthening sites in the copper alloy matrix, which is beneficial for suppressing copper grain growth, achieving fine-grain strengthening, and increasing the resistance to dislocation movement, but also... The synergistic multi-scale distribution of nano-CeO2 particles inhibits the growth of copper grains through both grain boundary blocking and intragranular anchoring, achieving a continuous grain refinement strengthening effect. This strengthening effect is superior to that of using single nano-Y2O3 particles and nano-CeO2 particles, effectively improving the tensile strength of copper alloy wires. Moreover, after the reinforcing phase particles, nano-Y2O3 particles and nano-CeO2 particles, cooperate to achieve a nanoscale dispersed distribution, the impact on electron scattering is small, avoiding the formation of large-size scattering sources through local agglomeration, and the conductivity can still be maintained at the level of 85.8-82.1% IACS.

[0016] 2. In this invention, a layer of nickel is first plated on the surface of the carbon fiber. Utilizing the better compatibility and bonding force between nickel and carbon fiber, a strongly bonded inner plating layer is formed on the carbon fiber surface. This nickel layer acts as an anchoring and transition layer, providing a stable and reliable substrate for the outer copper plating layer. Then, copper ions are reduced and deposited on the surface of the nickel layer to form a copper layer. Since nickel and copper have similar lattice constants, they can form a "metallurgical bond," creating a continuous conductive path between the carbon fiber and the copper alloy matrix. This effectively enhances the interfacial bonding force between the carbon fiber and the copper alloy matrix, promotes electron transport at the interface between the carbon fiber and the copper alloy matrix, avoids interfacial gaps between the carbon fiber and the copper alloy matrix, reduces electron scattering loss at the interface, eliminates contact resistance at heterogeneous interfaces, and thus improves the conductivity of the copper alloy wire. Simultaneously, the high strength characteristics of the carbon fiber can be transferred to the copper matrix through this composite plating layer of nickel and copper, forming a "rigid skeleton-flexible matrix" composite structure. When the alloy is under stress, the carbon fiber bears the main stress, while the copper alloy matrix disperses the stress and inhibits brittle fracture of the carbon fiber, thereby improving the mechanical properties of the copper alloy wire.

[0017] 3. In this invention, the amount of composite coated carbon fiber added is controlled at 0.8% to 2.4% of the weight of the pre-composite powder. Within this range, the composite coated carbon fiber can be uniformly dispersed in the alloy composite powder, promoting the formation of an effective stress transmission network and conductive path in the matrix, effectively balancing the conductivity and strength of the copper alloy wire. When the addition amount is less than 0.8%, the composite coated carbon fiber is sparsely distributed in the copper alloy matrix, failing to form a continuous stress transmission network and conductive path, resulting in insignificant strengthening and conductivity gains. When the addition amount exceeds 2.4%, the composite coated carbon fiber is prone to agglomeration, failing to fully coat the copper matrix, forming "interfacial voids" and "conductive islands," leading to a decrease in conductivity. Simultaneously, the mechanical properties of the copper alloy wire will deteriorate due to stress concentration caused by the agglomerates. Detailed Implementation

[0018] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1

[0020] A manufacturing process for a high-conductivity copper alloy wire specifically includes the following steps: S1: Preparation of CuCrZr alloy powder Copper powder, chromium powder, and zirconium powder were placed in a ball mill jar. Under argon protection, stainless steel grinding balls were added at a ball-to-material weight ratio of 12:1. The mixture was then ball-milled using a high-energy ball mill at a speed of 300 rpm for 32 hours to obtain CuCrZr alloy powder. The ratio of copper powder, chromium powder, and zirconium powder was: 0.7 wt% chromium powder, 0.2 wt% zirconium powder, with the remainder being copper powder. All three powders were spherical particles. S2: Preparation of pre-composite powder S2.1: Mix nano-Y2O3 particles with a particle size range of 30-50nm and nano-CeO2 particles with a particle size range of 10-20nm at a weight ratio of 1:1. After mixing evenly, a mixed powder is obtained. S2.2: 1.75 parts by weight of mixed powder were added to 250 parts by weight of anhydrous ethanol and ultrasonically dispersed for 20 min to obtain a mixed powder suspension. Under argon protection, 125 parts by weight of CuCrZr alloy powder were slowly added to the mixed powder suspension and stirred continuously for 2 h to fully impregnate the CuCrZr alloy powder in the mixed powder suspension to obtain a mixed slurry. S2.3: The mixed slurry is placed in a vacuum drying oven and dried at 80℃ for 3h, then ground and sieved to obtain a pre-composite powder; S3: Preparation of composite plated carbon fiber, S3.1: The carbon fiber is added to a roughening solution for oxidation roughening, and the solid-liquid mass ratio of the carbon fiber to the roughening solution is 1:20. The roughening solution is a mixed acid solution of concentrated nitric acid and concentrated sulfuric acid in a volume ratio of 3:1, and the stirring is performed in an 80℃ oil bath for 2h. After filtration, water washing to pH=7 and drying, the carbon fiber after roughening treatment is obtained; S3.2: The carbon fiber after roughening treatment is added to a sensitizing solution, and the solid-liquid mass ratio of the carbon fiber after roughening treatment to the sensitizing solution is 1:20. The composition of the sensitizing solution is: 30g / L stannous chloride, 30g / L hydrogen chloride and 2g tin particles. Ultrasonic dispersion is performed for 10min, and the solution is left to stand for 20min. After filtration, the carbon fiber after sensitizing treatment is obtained; S3.3: The carbon fiber after sensitizing treatment is added to an activating solution, and the solid-liquid mass ratio of the carbon fiber after sensitizing treatment to the activating solution is 1:25. The composition of the activating solution is: 0.4g / L palladium chloride, 20g / L hydrogen chloride. The solution is left to stand for 40min, and then after filtration, water washing and drying, the pretreated carbon fiber is obtained; S3.4: The pretreated carbon fiber is added to a plating solution, and the plating solution is prepared by using deionized water as a solvent and including the following components: 25g / L nickel sulfate, 30g / L sodium hypophosphite, 15g / L ammonium chloride, 15g / L sodium citrate. The pH value of the plating solution is 4. After sufficient soaking, the solution is placed in a water bath at 82℃ for continuous stirring for 45min. After filtration and drying, the nickel-plated carbon fiber is obtained; S3.5: A direct current stabilized power supply is used, the nickel-plated carbon fiber is used as a cathode, and a high-purity copper plate is used as an anode. The nickel-plated carbon fiber and the high-purity copper plate are placed in an electroplating solution, and the composition of the electroplating solution is: 50g / L copper sulfate, 100g / L potassium citrate, 0.35g / L OP-10 emulsifier, 12.5g / L potassium nitrate. The current density is controlled to be 1A / dm², the temperature is 25℃, and the electroplating time is 75min. After electroplating, the solution is washed with water and dried to obtain the composite plated carbon fiber; S4: Preparation of alloy composite powder, The pre-composite powder and the composite plated carbon fiber are placed in a ball milling tank, and the amount of the composite plated carbon fiber added is 1.6% of the weight of the pre-composite powder. Under the protection of argon, stainless steel balls are added in a ball-to-charge weight ratio of 12:1, and high-energy ball milling is performed. The ball milling speed is 300rpm, and the time is 9h to obtain the alloy composite powder; S5: Preparation of high-conductivity copper alloy wire, S5.1: Put the alloy composite powder into the mold for pressing, the pressure of pressing is 150 MPa, and a cylindrical alloy composite blank is obtained. The alloy composite blank is placed into a sintering furnace for sintering, the temperature is raised to 960 ℃ at a rate of 7.5 ℃ / min under argon protection, the pressure is 200 MPa, and the temperature is kept for 1.5 h. After the temperature keeping, the furnace is cooled down, and an alloy composite block is obtained; S5.2: The alloy composite block is placed into a heat treatment furnace and heated to 850 ℃. Then, the alloy composite block is quickly moved into a hydraulic machine for extrusion molding, and the extrusion ratio is 30. After the extrusion molding, the temperature is kept at 500 ℃ for 3 h. After the temperature keeping, the alloy composite block is air-cooled to room temperature, and a high-conductivity copper alloy wire is obtained.

[0021] Example 2

[0022] A preparation process of a high-conductivity copper alloy wire specifically includes the following steps. S1: Preparation of CuCrZr alloy powder, The copper powder, the chromium powder and the zirconium powder are placed into a ball milling tank, stainless steel milling balls are added under argon protection at a ball-to-charge weight ratio of 15:1, high-energy ball milling is performed by using a high-energy ball mill at a rotation speed of 400 rpm for 40 h, and CuCrZr alloy powder is obtained. The ratio of the copper powder, the chromium powder and the zirconium powder is as follows: the chromium powder is 0.8 wt%, the zirconium powder is 0.3 wt%, and the balance is the copper powder. The copper powder, the chromium powder and the zirconium powder are all spherical particles. S2: Preparation of pre-composite powder, S2.1: The nano Y2O3 particles with a particle size interval of 30-50 nm and the nano CeO2 particles with a particle size interval of 10-20 nm are stirred and mixed at a weight ratio of 1:1.5. After uniform mixing, a mixed powder is obtained. S2.2: 3 parts by weight of the mixed powder are added to 300 parts by weight of anhydrous ethanol, and ultrasonic dispersion is performed for 30 min to obtain a mixed powder suspension. Under argon protection, 150 parts by weight of CuCrZr alloy powder is slowly added to the mixed powder suspension, and continuous stirring is performed for 3 h to enable the CuCrZr alloy powder to be fully infiltrated in the mixed powder suspension, and a mixed slurry is obtained. S2.3: The mixed slurry is placed in a vacuum drying box and dried at 90 ℃ for 4 h. Subsequently, the mixed slurry is ground and sieved to obtain a pre-composite powder. S3: Preparation of composite coated carbon fiber, S3.1: The carbon fiber is added to a roughening solution for oxidation roughening. The solid-liquid mass ratio of the carbon fiber to the roughening solution is 1:20. The roughening solution is a mixed acid solution prepared by mixing concentrated nitric acid and concentrated sulfuric acid at a volume ratio of 3:1. The solution is stirred in an 80 ℃ oil bath for 2 h. After filtration, water washing to pH=7 and drying, the carbon fiber after roughening treatment is obtained. S3.2: The roughened carbon fiber is added into the sensitizing solution, the solid-liquid mass ratio of the roughened carbon fiber to the sensitizing solution is 1:20, the composition of the sensitizing solution is 30 g / L of stannous chloride, 30 g / L of hydrogen chloride and 2 g of tin particles, ultrasonic dispersion is performed for 10 min, standing is performed for 20 min, suction filtration is performed, and the sensitized carbon fiber is obtained; S3.3: The sensitized carbon fiber is added into the activating solution, the solid-liquid mass ratio of the sensitized carbon fiber to the activating solution is 1:25, the composition of the activating solution is 0.4 g / L of palladium chloride and 20 g / L of hydrogen chloride, standing is performed for 40 min, then suction filtration, water washing and drying are performed, and the pretreated carbon fiber is obtained; S3.4: The pretreated carbon fiber is added into the plating solution, the plating solution is prepared by using deionized water as a solvent and comprises the following components: 30 g / L of nickel sulfate, 35 g / L of sodium hypophosphite, 20 g / L of ammonium chloride and 20 g / L of sodium citrate, the pH value of the plating solution is 5, sufficient soaking is performed, then the plating solution is placed in a water bath at 90℃ and continuously stirred for 60 min, and then suction filtration and drying are performed, and the nickel-plated carbon fiber is obtained; S3.5: A direct current stabilized power supply is used, the nickel-plated carbon fiber is used as a cathode, a high-purity copper plate is used as an anode, the nickel-plated carbon fiber and the high-purity copper plate are placed in an electroplating solution, the composition of the electroplating solution is 60 g / L of copper sulfate, 120 g / L of potassium citrate, 0.4 g / L of OP-10 emulsifier and 15 g / L of potassium nitrate, the current density is controlled to be 1.5 A / dm2, the temperature is controlled to be 30℃, the electroplating time is 90 min, after the electroplating is completed, water washing and drying are performed, and the composite-coated carbon fiber is obtained; S4: Preparation of the alloy composite powder, The pre-composite powder and the composite-coated carbon fiber are placed in a ball milling tank, the amount of the composite-coated carbon fiber added is 2.4% of the weight of the pre-composite powder, stainless steel milling balls are added under argon protection at a ball-to-powder weight ratio of 15:1, high-energy ball milling is performed at a rotation speed of 400 rpm for 12 h, and the alloy composite powder is obtained; S5: Preparation of the high-conductivity copper alloy wire, S5.1: The alloy composite powder is placed in a mold for pressing, the pressing pressure is 200 MPa, a cylindrical alloy composite blank is obtained, the alloy composite blank is placed in a sintering furnace for sintering, the temperature is raised to 1000℃ at a temperature raising rate of 10℃ / min under argon protection, the pressure is 300 MPa, and the temperature is kept for 2 h, and then the temperature is lowered in the furnace, and an alloy composite block is obtained; S5.2: The alloy composite block is placed in a heat treatment furnace and heated to 900℃, then quickly moved into a hydraulic machine for extrusion forming at an extrusion ratio of 30, after the extrusion forming, the temperature is kept at 550℃ for 4 h, and then the temperature is air-cooled to room temperature, and a high-conductivity copper alloy wire is obtained.

[0023] Example 3

[0024] A preparation process of a high-conductivity copper alloy wire, specifically comprising the following steps: S1: preparation of CuCrZr alloy powder, The copper powder, chromium powder and zirconium powder are put into a ball mill tank, stainless steel balls are added under argon protection at a ball-to-charge weight ratio of 10:1, high-energy ball milling is performed using a high-energy ball mill at a rotation speed of 200 rpm for 24 h, and CuCrZr alloy powder is obtained, wherein the ratio of the copper powder, chromium powder and zirconium powder is: 0.6wt% of chromium powder, 0.1wt% of zirconium powder, and the balance is copper powder, and the copper powder, chromium powder and zirconium powder are all spherical particles; S2: preparation of pre-composite powder, S2.1: nano Y2O3 particles with a particle size range of 30-50 nm and nano CeO2 particles with a particle size range of 10-20 nm are stirred and mixed according to a weight ratio of 1:0.5, and after uniform mixing, a mixed powder is obtained; S2.2: 0.5 parts by weight of the mixed powder is added to 200 parts by weight of anhydrous ethanol, ultrasonic dispersion is performed for 10 min to obtain a mixed powder suspension, 100 parts by weight of CuCrZr alloy powder is slowly added to the mixed powder suspension under argon protection, and stirring is continued for 1 h to allow the CuCrZr alloy powder to fully infiltrate the mixed powder suspension, thereby obtaining a mixed slurry; S2.3: the mixed slurry is placed in a vacuum drying oven and dried at 70°C for 2 h, and then ground and sieved to obtain a pre-composite powder; S3: preparation of a composite plated carbon fiber, S3.1: the carbon fiber is added to a roughening solution for oxidation roughening, the solid-liquid mass ratio of the carbon fiber to the roughening solution is 1:20, the roughening solution is a mixed acid solution prepared by mixing concentrated nitric acid and concentrated sulfuric acid at a volume ratio of 3:1, and the solution is stirred in an 80°C oil bath for 2 h, then the carbon fiber is subjected to suction filtration, water washing until pH=7, and drying to obtain the carbon fiber after roughening treatment; S3.2: the carbon fiber after roughening treatment is added to a sensitization solution, the solid-liquid mass ratio of the carbon fiber after roughening treatment to the sensitization solution is 1:20, the composition of the sensitization solution is: 30g / L of stannous chloride, 30g / L of hydrogen chloride and 2g of tin particles, ultrasonic dispersion is performed for 10 min, the solution is left to stand for 20 min, and then suction filtration is performed to obtain the carbon fiber after sensitization treatment; S3.3: the carbon fiber after sensitization treatment is added to an activation solution, the solid-liquid mass ratio of the carbon fiber after sensitization treatment to the activation solution is 1:25, the composition of the activation solution is: 0.4g / L of palladium chloride and 20g / L of hydrogen chloride, the solution is left to stand for 40 min, and then the carbon fiber is subjected to suction filtration, water washing and drying to obtain the pretreated carbon fiber; S3.4: The pretreated carbon fiber is added into a plating solution, the plating solution is prepared by using deionized water as a solvent and comprises the following components: 20 g / L of nickel sulfate, 25 g / L of sodium hypophosphite, 10 g / L of ammonium chloride, and 10 g / L of sodium citrate, the pH value of the plating solution is 3, the carbon fiber is fully immersed, then the carbon fiber is placed in a water bath at 75°C for continuous stirring for 30 min, and then the carbon fiber is filtered and dried to obtain a nickel-plated carbon fiber; S3.5: A direct current stabilized power supply is used, the nickel-plated carbon fiber is used as a cathode, and a high-purity copper plate is used as an anode, the nickel-plated carbon fiber and the high-purity copper plate are placed in an electroplating solution, the electroplating solution comprises the following components: 40 g / L of copper sulfate, 80 g / L of potassium citrate, 0.3 g / L of OP-10 emulsifier, and 10 g / L of potassium nitrate, the current density is controlled to be 0.5 A / dm2, the temperature is controlled to be 20°C, the electroplating time is 60 min, after the electroplating is completed, the electroplated carbon fiber is washed with water and dried to obtain a composite plated carbon fiber; S4: Preparation of the alloy composite powder, The pre-composite powder and the composite plated carbon fiber are placed in a ball milling tank, the amount of the composite plated carbon fiber added is 0.8% of the weight of the pre-composite powder, stainless steel milling balls are added under argon protection at a ball-to-powder weight ratio of 10:1, and the pre-composite powder is ball milled by using a high-energy ball mill at a rotation speed of 200 rpm for 6 h to obtain the alloy composite powder; S5: Preparation of the high-conductivity copper alloy wire, S5.1: The alloy composite powder is placed in a mold for pressing at a pressure of 100 MPa to obtain a cylindrical alloy composite blank, the alloy composite blank is placed in a sintering furnace for sintering, the temperature is raised to 920°C at a temperature raising rate of 5°C / min under argon protection, the pressure is 100 MPa, and the temperature is maintained for 1 h, and then the temperature is lowered with the furnace to obtain an alloy composite block; S5.2: The alloy composite block is placed in a heat treatment furnace and heated to 800°C, then quickly moved into a hydraulic machine for extrusion forming at an extrusion ratio of 30, and then the alloy composite block is maintained at 450°C for 2 h after the extrusion forming, and then the alloy composite block is air-cooled to room temperature to obtain the high-conductivity copper alloy wire.

[0025] Comparative Example 1 Comparative Example 1 is different from Example 1 in that step S2.1 is removed, and the mixed powder in step S2.2 is replaced by equal weight parts of nano Y2O3 particles with a particle size interval of 30-50 nm, and the remaining steps are unchanged, to prepare a high-conductivity copper alloy wire, which is denoted as Comparative Example 1.

[0026] Comparative Example 2 Comparative Example 2 is different from Example 1 in that step S2.1 is removed, the mixed powder in step S2.2 is replaced with equal weight parts of nano-CeO2 particles with a particle size range of 10-20 nm, and the remaining steps are unchanged, to produce a high-conductivity copper alloy wire, which is denoted as Comparative Example 2.

[0027] Comparative Example 3 Comparative Example 3 is different from Example 1 in that step S2 is removed, the pre-composite powder in step S4 is replaced with equal weight parts of the CuCrZr alloy powder obtained in step S1, and the remaining steps are unchanged, to produce a high-conductivity copper alloy wire, which is denoted as Comparative Example 3.

[0028] Comparative Example 4 Comparative Example 4 is different from Example 1 in that step S3.5 is removed, the composite-coated carbon fiber in step S4 is replaced with equal weight parts of the nickel-plated carbon fiber obtained in step S3.4, and the remaining steps are unchanged, to produce a high-conductivity copper alloy wire, which is denoted as Comparative Example 4.

[0029] Comparative Example 5 Comparative Example 5 is different from Example 1 in that step S3.4 is removed, the nickel-plated carbon fiber in S3.5 is replaced with equal weight parts of the pretreated carbon fiber obtained in step S3.3, copper is plated directly on the surface of the pretreated carbon fiber to obtain a copper-plated carbon fiber, the composite-coated carbon fiber in step S4 is replaced with the copper-plated carbon fiber, and the remaining steps are unchanged, to produce a high-conductivity copper alloy wire, which is denoted as Comparative Example 5.

[0030] Comparative Example 6 Comparative Example 6 is different from Example 1 in that step S3 is removed, the composite-coated carbon fiber in step S4 is replaced with equal weight parts of carbon fiber, and the remaining steps are unchanged, to produce a high-conductivity copper alloy wire, which is denoted as Comparative Example 6.

[0031] Comparative Example 7 Comparative Example 7 is different from Example 1 in that in step S4, the amount of composite-coated carbon fiber added is 0.6% of the weight of the pre-composite powder, and the remaining steps are unchanged, to produce a high-conductivity copper alloy wire, which is denoted as Comparative Example 7.

[0032] Comparative Example 8 Comparative Example 8 is different from Example 1 in that in step S4, the amount of composite-coated carbon fiber added is 0.7% of the weight of the pre-composite powder, and the remaining steps are unchanged, to produce a high-conductivity copper alloy wire, which is denoted as Comparative Example 8.

[0033] Comparative Example 9 Comparative Example 9 is different from Example 1 in that in step S4, the amount of the composite plated carbon fiber added is 2.5% by weight of the pre-composite powder, and the other steps remain unchanged, to prepare a high-conductivity copper alloy wire, which is denoted as Comparative Example 9.

[0034] Comparative Example 10 Comparative Example 10 is different from Example 1 in that in step S4, the amount of the composite plated carbon fiber added is 2.6% by weight of the pre-composite powder, and the other steps remain unchanged, to prepare a high-conductivity copper alloy wire, which is denoted as Comparative Example 10.

[0035] The high-conductivity copper alloy wires prepared in Examples 1-3 and Comparative Examples 1-10 are tested for tensile strength according to the standard of GB / T 228-2002; and the high-conductivity copper alloy wires prepared in Examples 1-3 and Comparative Examples 1-10 are tested for conductivity using a digital eddy current conductivity meter, and the results are shown in Table 1.

[0036] Table 1: Group Tensile strength (MPa) Electrical conductivity (% IACS) Example 1 587.4 85.8 Example 2 584.2 83.6 Example 3 579.9 82.1 Comparative Example 1 552.6 72.4 Comparative Example 2 549.1 75.7 Comparative Example 3 458.5 88.5 Comparative Example 4 557.3 73.3 Comparative Example 5 566.8 76.1 Comparative Example 6 540.5 71.4 Comparative Example 7 554.1 75.5 Comparative Example 8 568.8 78.2 Comparative Example 9 573.6 80.3 Comparative Example 10 562.4 78.9 As can be seen from Table 1, the high-conductivity copper alloy wires prepared in Examples 1-3 are superior to the high-conductivity copper alloy wires prepared in Comparative Examples 1-10 in terms of tensile strength and conductivity, with the tensile strength being ≥ 579.9 MPa and the conductivity being maintained at a level of 85.8-82.1% IACS.

[0037] From the test results of Examples 1-3 and Comparative Examples 1-3, it can be seen that Comparative Example 3 does not incorporate reinforcing phase particles, and only uses CuCrZr alloy powder to prepare the high-conductivity copper alloy wire, and the conductivity thereof is 88.5% IACS, and the tensile strength is only 458.5 MPa, while the conductivity of the high-conductivity copper alloy wire of Examples 1-3 is reduced to a certain extent, but still maintains at the level of 85.8-82.1% IACS, and the tensile strength of the high-conductivity copper alloy wire of Examples 1-3 is significantly higher than that of Comparative Example 3, indicating that although the incorporation of reinforcing phase particles will have a certain impact on the conductivity, it can significantly improve the tensile strength of the high-conductivity copper alloy wire while ensuring high conductivity, and a good balance between high strength and high conductivity is achieved. Comparative Example 1 only incorporates nano Y2O3 particles with a particle size range of 30-50 nm, and Comparative Example 2 only incorporates nano CeO2 particles with a particle size range of 10-20 nm, and in terms of tensile strength, the tensile strength of Comparative Example 1 is 552.6 MPa, and the conductivity is 72.4% IACS, and the tensile strength of Comparative Example 2 is 549.1 MPa, and the conductivity is 75.7% IACS, both of which are lower than the tensile strength and conductivity of Examples 1-3, indicating that the incorporation of single nano Y2O3 particles or nano CeO2 particles has limited effect on the improvement of the tensile strength of the copper alloy wire, and is also prone to a significant decrease in conductivity, while the simultaneous incorporation of nano Y2O3 particles and nano CeO2 particles can synergistically play the role of reinforcing phase particles, form multiple-scale strengthening sites in the copper alloy matrix, more effectively inhibit the growth of copper grains, increase the resistance to dislocation movement, and reduce the influence of electron scattering, thereby maintaining a high level of conductivity while ensuring high tensile strength.

[0038] From the test results of Examples 1-3 and Comparative Examples 4-6, it can be seen that the high-conductivity copper alloy wire obtained in Examples 1-3 has better conductivity and tensile strength than Comparative Examples 4-6 which add copper-plated carbon fibers, nickel-plated carbon fibers or carbon fibers, indicating that coating a nickel layer and a copper layer on the surface of the carbon fiber in sequence can effectively improve the interfacial bonding strength between the carbon fiber and the copper alloy matrix, promote the transmission of electrons at the carbon fiber-copper matrix interface, reduce the scattering loss of electrons at the interface, improve the conductivity of the high-conductivity copper alloy wire, and better optimize the mechanical properties of the high-conductivity copper alloy wire.

[0039] From the test results of Examples 1-3 and Comparative Examples 7-10, it can be seen that when the addition amount of the composite plated carbon fiber is less than or exceeds 0.8-2.4% of the weight of the pre-composite powder, the conductivity and mechanical properties of the high-conductivity copper alloy wire will be affected, wherein when the addition amount of the composite plated carbon fiber is less than 0.8% of the weight of the pre-composite powder, the conductivity and mechanical properties are insufficiently enhanced, and when the addition amount of the composite plated carbon fiber is greater than 2.4% of the weight of the pre-composite powder, the conductivity and mechanical properties are deteriorated.

[0040] It is to be understood that the above description is intended to be illustrative and not restrictive. Many other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the application should, therefore, be determined not with reference to the above description, but instead with reference to the appended claims, along with their full scope of equivalents.

Claims

1. A process for producing a high-conductivity copper alloy wire, characterized by, The method comprises the following steps: The nano Y2O3 particles and the nano CeO2 particles are mixed uniformly, and then the obtained mixed powder is added into anhydrous ethanol, and CuCrZr alloy powder is added under argon protection, and then stirring, vacuum drying and grinding are performed to obtain a pre-composite powder; The pre-composite powder and the composite plated carbon fiber are placed in a ball mill tank, the adding amount of the composite plated carbon fiber is 0.8-2.4% of the weight of the pre-composite powder, stainless steel grinding balls are added under the weight ratio of ball to material (10-15):1, and high-energy ball milling is performed at a ball milling speed of 200-400 rpm for 6-12 hours to obtain an alloy composite powder. The alloy composite powder is subjected to pressing, sintering, heat treatment, extrusion molding and aging treatment to obtain a high-conductivity copper alloy wire. The composite plated carbon fiber is carbon fiber which is plated with a nickel layer and a copper layer on the surface in sequence.

2. The process for preparing a high-conductivity copper alloy wire according to claim 1, wherein The preparation of the CuCrZr alloy powder comprises the following steps: The copper powder, the chromium powder and the zirconium powder are placed in a ball mill tank, stainless steel grinding balls are added under the weight ratio of ball to material (10-15):1 under argon protection, and high-energy ball milling is performed at a ball milling speed of 200-400 rpm for 24-40 hours to obtain the CuCrZr alloy powder.

3. The process for preparing a high-conductivity copper alloy wire according to claim 2, wherein The composition of the CuCrZr alloy powder comprises: The chromium powder is 0.6-0.8 wt%, the zirconium powder is 0.1-0.3 wt%, and the balance is copper powder, and the copper powder, the chromium powder and the zirconium powder are all spherical particles.

4. The process for preparing a high conductive copper alloy wire according to claim 1, wherein The specific preparation steps of the pre-composite powder comprise: The nano Y2O3 particles and the nano CeO2 particles are mixed according to the weight ratio of 1:(0.5-1.5), and then the mixed powder is obtained after mixing uniformly; 0.5-3 parts by weight of the mixed powder is added into 200-300 parts by weight of anhydrous ethanol, ultrasonic dispersion is performed for 10-30 minutes to obtain a mixed powder suspension, 100-150 parts by weight of CuCrZr alloy powder is slowly added into the mixed powder suspension under argon protection, and continuous stirring is performed for 1-3 hours to make the CuCrZr alloy powder fully infiltrate in the mixed powder suspension to obtain a mixed slurry; The mixed slurry is placed in a vacuum drying box and dried at 70-90°C for 2-4 hours, and then ground and sieved to obtain the pre-composite powder.

5. The process for preparing a high conductive copper alloy wire according to claim 1, wherein The specific preparation steps of the alloy composite powder comprise: The pre-composite powder and the composite plated carbon fiber are placed in a ball mill tank, the adding amount of the composite plated carbon fiber is 0.8-2.4% of the weight of the pre-composite powder, stainless steel grinding balls are added under the weight ratio of ball to material (10-15):1 under argon protection, and high-energy ball milling is performed at a ball milling speed of 200-400 rpm for 6-12 hours to obtain an alloy composite powder.

6. The process for preparing a high-conductivity copper alloy wire according to claim 5, wherein The specific preparation steps of the composite plated carbon fiber comprise: The carbon fiber is subjected to roughening, sensitization and activation treatment to obtain pretreated carbon fiber, the pretreated carbon fiber is added into a plating solution for full infiltration, and then placed in a water bath at 75-90°C for continuous stirring for 30-60 minutes, and then subjected to suction filtration and drying to obtain nickel-plated carbon fiber. The direct current stabilized power supply is adopted, the nickel-plated carbon fiber is used as the cathode, the high-purity copper plate is used as the anode, the nickel-plated carbon fiber and the high-purity copper plate are put into the electroplating solution, the current density is controlled to be 0.5-1.5 A / dm 2 , the temperature is controlled to be 20-30 DEG C, the electroplating time is controlled to be 60-90 min, after the electroplating is completed, the water washing and drying are carried out, and the composite plated carbon fiber is obtained.

7. The process for preparing a high conductive copper alloy wire according to claim 6, wherein The plating solution uses deionized water as a solvent and comprises the following components: 20-30 g / L of nickel sulfate, 25-35 g / L of sodium hypophosphite, 10-20 g / L of ammonium chloride, and 10-20 g / L of sodium citrate, and the pH value of the plating solution is 3-5; the electroplating solution comprises the following components: 40-60 g / L of copper sulfate, 80-120 g / L of potassium citrate, 0.3-0.4 g / L of OP-10 emulsifier, and 10-15 g / L of potassium nitrate.

8. The process for producing a high-conductivity copper alloy wire according to claim 7, wherein The specific preparation steps of the high-conductivity copper alloy wire include: The alloy composite powder is put into a mold for pressing, the pressing pressure is 100-200 MPa, and an alloy composite blank is obtained; the alloy composite blank is put into a sintering furnace for sintering, the temperature is raised to 920-1000 DEG C at a temperature raising rate of 5-10 DEG C / min under argon protection, the pressure is 100-300 MPa, and the temperature is kept for 1-2 h; after the temperature keeping, the furnace is cooled down, and an alloy composite block is obtained; The alloy composite block is put into a heat treatment furnace and heated to 800-900 DEG C, then quickly moved into a hydraulic machine for extrusion molding; after the extrusion molding, the temperature is kept at 450-550 DEG C for 2-4 h; after the temperature keeping, the temperature is cooled down to room temperature, and a high-conductivity copper alloy wire is obtained.

9. The process for producing a high-conductivity copper alloy wire according to claim 8, wherein The extrusion ratio of the extrusion molding is 20-40.

10. A high-conductivity copper alloy wire, characterized by, The high-conductivity copper alloy wire is prepared by the preparation process of the high-conductivity copper alloy wire according to any one of the above claims 1-9.