High-strength and high-plasticity ultra-fine copper alloy wire, preparation method and application thereof

Abstract

This invention belongs to the field of copper alloy wire technology, and particularly relates to a high-strength, high-ductility, ultrafine copper alloy wire, its preparation method, and its application. The process includes batching and casting, single extrusion, solution treatment, continuous extrusion, drawing, and online graded continuous annealing. It can produce high-strength, high-conductivity, and high-ductility copper alloy wires with a diameter of 0.08–0.20 mm and a precipitation density of 1 × 10⁻⁶ precipitates of 5–20 nm in both transverse and longitudinal directions. 23 ~5×10 23 m ‑3 The average grain size in both transverse and longitudinal sections is 0.2–1 μm, with a corresponding tensile strength of 450–680 MPa, electrical conductivity of 65%–92% IACS, elongation of 10%–20%, and a bending cycle of 1×10⁻⁶. 10 ~5×10 10 Secondly, its performance fully meets the urgent needs of emerging industries such as aerospace, 5G communications, and new energy vehicles for high-end copper alloy conductor materials.

Description

Technical Field

[0001] This invention belongs to the field of copper alloy wire technology, and particularly relates to a high-strength, high-plasticity ultrafine copper alloy wire, its preparation method, and its application. Background Technology

[0002] With the rapid development of modern science and technology, aerospace, 5G communication, medical, and new energy vehicles have increasingly higher requirements for the functional characteristics of information terminal products. Not only are fast current and signal transmission required, but cables also do not need to generate significant heat during operation and do not need to occupy too much space. Weight reduction is also a key requirement. This requires conductor materials to have high strength, high conductivity, and excellent elongation, i.e., high plasticity.

[0003] Currently, widely used conductor materials include copper, aluminum, copper-silver alloys, copper-tin alloys, and copper-chromium alloys. Copper and aluminum have high conductivity and good ductility, but lower strength and poor resistance to thermal softening, so they are mostly used in environments with lower requirements for strength and temperature. Compared with pure metal conductors, alloy conductor materials can have higher strength, better oxidation resistance, and better temperature resistance, but they have low ductility and poor flexibility, making them difficult to wire later. According to the size effect, the smaller the size, the worse the ductility of the material. Especially for age-hardening alloys, in order to achieve high strength and high conductivity, high-temperature solution treatment and aging treatment are required. It is difficult to control the grain size and aging precipitation simultaneously. In most cases, the ductility of the material is sacrificed to achieve high strength and high conductivity. Therefore, how to simultaneously obtain high strength and high conductivity while significantly improving the ductility of the alloy is a major technical challenge in the preparation of high-end conductor materials, and it is also an urgent need to meet the rapid development of emerging industries such as aerospace, 5G communication, and new energy vehicles.

[0004] Therefore, developing an ultrafine copper alloy wire that simultaneously possesses high strength, high conductivity, and high plasticity is of great significance for enriching and developing my country's high-performance copper alloy material system. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a high-strength, high-plasticity ultrafine copper alloy wire, its preparation method, and its application.

[0006] The technical solution of this invention is as follows: A high-strength, high-ductility ultrafine copper alloy wire, wherein the ultrafine copper alloy wire is mainly composed of the following raw materials in the indicated mass percentages: The composition consists of any two of the following elements: Cr 0.1%–1.0%, Zr 0.02%–0.15%, Ag 0.05%–0.2%, Mg 0.02%–0.2%, Sn 0.02%–0.2%, and Si 0.002%–0.05%, with the remainder being Cu. Alternatively, Ag 0.05%–0.1%, Ni 1.0%–2.0% and Be 0.15%–0.3%, with the remainder being Cu.

[0007] Furthermore, the diameter of the ultrafine copper alloy wire is 0.08–0.20 mm.

[0008] Furthermore, the copper alloy wire has a precipitate density of 5–20 nm in both the transverse and longitudinal cross-sections of 1 × 10⁻⁶. 23 ~5×10 23 m -3 The average grain size in both transverse and longitudinal sections is 0.2–1 μm.

[0009] Furthermore, the copper alloy wire has a conductivity of 65–92% IACS, an elongation of 10–20%, and a bending cycle of 1×10⁻⁶. 10 ~5×10 10 Second-rate.

[0010] The technical solution of the present invention also provides a method for preparing the above-mentioned high-strength and high-ductility ultrafine copper alloy wire, comprising the following steps: Step S1: Batching and casting. The prepared raw materials are melted in a vacuum induction furnace and then semi-continuously cast. The melting temperature is 1200-1400℃, and the casting temperature is controlled at 1200-1350℃. After holding at the temperature for 30 minutes, the copper alloy ingot is cast. Step S2, single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating. The holding temperature is 800-900℃ and the holding time is 4-6h. Then the temperature is raised to 920-960℃ and held for 1-6h. After that, a single extrusion is performed at an extrusion ratio of 60-100. After extrusion, the copper alloy rod is cooled by water cooling to obtain copper alloy rod. Step S3, solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 900-1000℃, and the temperature is held for 1-6 hours before being cooled by water cooling. Step S4: Continuous extrusion. The copper alloy rod treated in step S3 is subjected to surface oxidation removal, followed by continuous extrusion. The extrusion roller is heated to 450-550℃, the extrusion speed is 12-20 r / min, the number of extrusion passes is 10-15, the extrusion ratio is 10-35, and the rod is cooled with a mixture of alcohol and water. Step S5: Drawing treatment. The bar material after step S4 is surface treated and then cold-drawn at a processing rate of 80-99.9% to obtain copper alloy wire. Step S6: Online graded continuous annealing treatment. The copper alloy wire obtained in step S5 is placed in an online continuous annealing furnace for graded online annealing treatment to obtain the final copper alloy wire. During the online continuous annealing treatment, the first-stage annealing temperature is controlled at 600-700℃, the second-stage annealing temperature is controlled at 400-500℃, and the winding speed is controlled at 50-120m / min to obtain the final copper alloy wire.

[0011] Furthermore, in step S6, the final copper alloy wire has a diameter of 0.08–0.20 mm and a precipitation density of 1 × 10⁻⁶ precipitates of 5–20 nm in both the transverse and longitudinal cross-sections. 23 ~5×10 23 m -3 The average grain size in both transverse and longitudinal sections is 0.2–1 μm.

[0012] Furthermore, the final copper alloy wire in step S6 has a tensile strength of 450–680 MPa, a conductivity of 65%–92% IACS, an elongation of 10%–20%, and a bending cycle of 1×10⁻⁶. 10 ~5×10 10 Second-rate.

[0013] Furthermore, the specific process of step S1 is as follows: Before melting, electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, and any two of pure silver, copper-silicon master alloy, pure magnesium, and pure tin are added to a vacuum induction furnace. The temperature is raised to 1250-1350℃. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1200-1250℃. After holding at this temperature for 30 minutes, semi-continuous casting is carried out to obtain copper alloy ingots.

[0014] Furthermore, the specific process of step S1 is as follows: Before melting, electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, pure silver, electrolytic nickel and copper-beryllium master alloy are added to a vacuum induction furnace, the temperature is raised to 1300-1400℃, and after the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1250-1350℃, and semi-continuous casting is carried out after holding at this temperature for 30 minutes.

[0015] The present invention also provides the application of the ultrafine copper alloy wire or the ultrafine copper alloy wire prepared by the preparation method described above in wires, cables and precision connectors.

[0016] Compared with the prior art, the beneficial effects of the preparation method and application of the high-strength, high-ductility ultrafine copper alloy wire provided by the present invention are as follows: 1. The ultrafine copper alloy wire provided by this invention has a diameter of 0.08–0.20 mm, a tensile strength of up to 680 MPa, a conductivity of up to 92% IACS, an elongation of up to 20%, and a bending life of up to 5 × 10⁻⁶ cycles. 10 Secondly, with a single wire diameter of no more than 0.2mm, it simultaneously possesses ultra-high strength, high conductivity, and excellent fatigue resistance, as well as good high temperature resistance, resulting in excellent overall performance. 2. In the preparation method of the ultrafine copper alloy wire provided by the present invention: 1) For age-hardened copper alloys, the strength of the alloy mainly comes from the precipitation of nanoscale precipitates during the aging process. In order to achieve the effect of age precipitation, high-temperature solid solution treatment is required, at which time the internal grain structure of the alloy appears particularly coarse. According to the size effect theory, when the wire diameter is in the micrometer range, the smaller the size, the worse the plasticity of the material, which reduces the flexibility of the material and is not conducive to the layout in subsequent use. Based on the phase inhibition of high strength, plasticity and conductivity of the ultrafine wire, this invention first performs continuous extrusion of the solid solution alloy material with large plastic deformation. Due to the strong shear deformation that occurs during continuous extrusion, there will be thermal changes inside the material, and shear deformation and phase transformation will occur simultaneously. However, since the material extrusion process is relatively short, some solute atoms inside the material are still not fully precipitated. At this time, the material structure is a fine grain structure, nanoscale precipitates and some solute atoms dissolved in the matrix. In order to allow solute atoms to precipitate during the subsequent deformation aging process, the solute atoms are subjected to intense pull deformation. At this time, the grains are clearly broken and have a large number of dislocation defects and deformation energy, which provide the driving force for subsequent aging precipitation.

[0017] 2) In order to effectively control the subsequent aging precipitation and grain size of the material, this invention uses a self-developed graded online continuous annealing device, which can realize online continuous partitioned annealing treatment of the material. It can first perform rapid annealing treatment at a higher temperature to induce recrystallization of the alloy, and then perform rapid annealing treatment at a lower temperature to induce precipitation of a large number of precipitates. The strength and conductivity of the alloy are significantly improved. By controlling the grain size through temperature and annealing rate, the alloy can have micro-nano-scale grain size, effectively solving the technical bottleneck of the difficulty in coordinating the control of high strength, high plasticity and high conductivity of alloy materials. Detailed Implementation

[0018] The technical solution 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] A high-strength, high-ductility ultrafine copper alloy wire, wherein the ultrafine copper alloy wire is mainly composed of the following raw materials in the indicated mass percentages: The composition consists of any two of the following elements: Cr 0.1%–1.0%, Zr 0.02%–0.15%, Ag 0.05%–0.2%, Mg 0.02%–0.2%, Sn 0.02%–0.2%, and Si 0.002%–0.05%, with the remainder being Cu. Alternatively, Ag 0.05%–0.1%, Ni 1.0%–2.0% and Be 0.15%–0.3%, with the remainder being Cu.

[0020] In this invention, the diameter of the ultrafine copper alloy wire is 0.08 to 0.20 mm.

[0021] In this invention, the copper alloy wire has a precipitate density of 1×10⁻⁶ precipitates with a cross-sectional area of ​​5–20 nm. 23 ~5×10 23 m -3 The average grain size in both transverse and longitudinal sections is 0.2–1 μm.

[0022] In this invention, the copper alloy wire has a conductivity of 65%–92% IACS, an elongation of 10%–20%, and a bending cycle of 1×10⁻⁶. 10 ~5×10 10 Second-rate.

[0023] The preparation method of the above-mentioned high-strength and high-ductility ultrafine copper alloy wire in this invention includes the following steps: Step S1: Batching and casting. The prepared raw materials are melted in a vacuum induction furnace and then semi-continuously cast. The melting temperature is 1200-1400℃, and the casting temperature is controlled at 1200-1350℃. After holding at the temperature for 30 minutes, the copper alloy ingot is cast. Step S2, single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating. The holding temperature is 800-900℃ and the holding time is 4-6h. Then the temperature is raised to 920-960℃ and held for 1-6h. After that, a single extrusion is performed at an extrusion ratio of 60-100. After extrusion, the copper alloy rod is cooled by water cooling to obtain copper alloy rod. Step S3, solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 900-1000℃, and the temperature is held for 1-6 hours before being cooled by water cooling. Step S4: Continuous extrusion. The copper alloy rod treated in step S3 is subjected to surface oxidation removal, followed by continuous extrusion. The extrusion roller is heated to 450-550℃, the extrusion speed is 12-20 r / min, the number of extrusion passes is 10-15, the extrusion ratio is 10-35, and the rod is cooled with a mixture of alcohol and water. Step S5: Drawing treatment. The bar material after step S4 is surface treated and then cold-drawn at a processing rate of 80% to 99.9% to obtain copper alloy wire. Step S6: Online graded continuous annealing treatment. The copper alloy wire obtained in step S5 is placed in an online annealing furnace for graded online continuous annealing treatment to obtain the final copper alloy wire. During the online continuous annealing treatment, the first-stage annealing temperature is controlled at 600-700℃, the second-stage annealing temperature is controlled at 400-500℃, and the winding speed is controlled at 50-120m / min to obtain the final copper alloy wire.

[0024] In step S6 of this invention, the final copper alloy wire has a diameter of 0.08–0.20 mm and a precipitate density of 1 × 10⁻⁶ nm in both the transverse and longitudinal cross-sections, with a precipitate density of 5–20 nm. 23 ~5×10 23 m -3 The average grain size in both transverse and longitudinal sections is 0.2–1 μm.

[0025] The final copper alloy wire in step S6 of this invention has a tensile strength of 450–680 MPa, a conductivity of 65%–92% IACS, an elongation of 10%–20%, and a bending cycle of 1×10⁻⁶. 10 ~5×10 10 Second-rate.

[0026] The specific process of step S1 in this invention is as follows: Before smelting, electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, and any two of pure silver, copper-silicon master alloy, pure magnesium, and pure tin are added to a vacuum induction furnace. The temperature is raised to 1250-1350°C. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1200-1250°C. After holding at this temperature for 30 minutes, semi-continuous casting is carried out to obtain copper alloy ingots.

[0027] The specific process of step S1 in this invention is as follows: Before melting, electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, pure silver, electrolytic nickel and copper-beryllium master alloy are added to a vacuum induction furnace, the temperature is raised to 1300-1400℃, and after the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1250-1350℃, and semi-continuous casting is carried out after holding at this temperature for 30 minutes.

[0028] The ultrafine copper alloy wire described in this invention or the ultrafine copper alloy wire prepared by the described preparation method is used in wires, cables and precision connectors. Example 1

[0029] The copper alloy in this embodiment is smelted using the following raw materials: electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, pure silver, and pure magnesium; the composition of the alloy is shown in Example 1 of Table 1.

[0030] Step S1, Batching and Casting: Before smelting, electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, pure silver and pure magnesium are added to a vacuum induction furnace. The temperature is raised to 1350℃. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1250℃. After holding at the temperature for 30 minutes, semi-continuous casting is carried out to obtain copper alloy ingots. Step S2, Single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating, and the holding temperature is 800℃ for 6 hours. Then the temperature is raised to 920℃ and held for 6 hours. After that, a single extrusion is performed at an extrusion ratio of 100. After extrusion, the copper alloy rod is cooled by water cooling to obtain copper alloy rod. Step S3, Solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 900℃, and after holding at the temperature for 6 hours, it is cooled by water cooling. Step S4, Continuous extrusion: The copper alloy rod treated in step S3 is subjected to surface oxidation removal, and then continuous extrusion is performed. The extrusion roller heating temperature is 550℃, the extrusion speed is 12r / min, the extrusion passes are 15, the extrusion ratio is 35, and the rod is cooled with a mixture of alcohol and water. Step S5, drawing process: The bar material after step S4 is surface treated, and then cold drawn at a processing rate of 80% to obtain copper alloy wire. Step S6, Online graded continuous annealing: The copper alloy wire obtained in step S5 is placed in an online annealing furnace for graded online continuous annealing to obtain the final copper alloy wire; during the online continuous annealing process, the first-stage annealing temperature is controlled at 600℃, the second-stage annealing temperature is controlled at 500℃, and the take-up speed is controlled at 120m / min.

[0031] The microstructure and properties of the ultrafine copper alloy wire were tested after the above-mentioned smelting, casting, extrusion, solution treatment, continuous extrusion, drawing and online graded continuous annealing processes, as shown in Example 1 in Tables 1, 2 and 3. Example 2

[0032] The copper alloy in this embodiment was smelted using the following raw materials: electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, pure tin, and pure magnesium. The composition of the alloy is shown in Example 2 of Table 1.

[0033] Step S1, Batching and Casting: Before smelting, electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, pure tin and pure magnesium are added to the vacuum induction furnace. The temperature is raised to 1250℃. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1200℃. After holding at the temperature for 30 minutes, semi-continuous casting is carried out to produce copper alloy ingots. Step S2, Single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating, and the holding temperature is 900℃ for 4 hours. Then the temperature is raised to 960℃ and held for 1 hour. After that, a single extrusion is performed at an extrusion ratio of 60. After extrusion, the copper alloy rod is cooled by water cooling to obtain copper alloy rod. Step S3, Solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 1000℃, the holding time is 1 hour, and then it is cooled by water cooling. Step S4, Continuous extrusion: The copper alloy rod treated in step S3 is subjected to surface oxidation removal, and then continuous extrusion is performed. The extrusion roller is heated to 450℃, the extrusion speed is 20r / min, the extrusion passes are 10, the extrusion ratio is 10, and the rod is cooled with a mixture of alcohol and water. Step S5, drawing process: The bar material after step S4 is surface treated, and then cold drawn at a processing rate of 99.9% to obtain copper alloy wire. Step S6, Online graded continuous annealing treatment: The copper alloy wire obtained in step S5 is placed in an online annealing furnace for graded online continuous annealing treatment to obtain the final copper alloy wire; during the online continuous annealing treatment, the first-stage annealing temperature is controlled at 700℃, the second-stage annealing temperature is controlled at 400℃, and the take-up speed is controlled at 50m / min.

[0034] The microstructure and properties of the ultrafine copper alloy wire were tested after the above-mentioned smelting, casting, extrusion, solution treatment, continuous extrusion, drawing and online graded continuous annealing processes, as shown in Example 2 in Tables 1, 2 and 3. Example 3

[0035] The copper alloy in this embodiment was smelted using the following raw materials: electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, pure tin, and pure silver. The composition of the alloy is shown in Table 1, Example 3.

[0036] Step S1, Melting and Casting: Before melting, electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, pure tin and pure silver are added to a vacuum induction furnace. The temperature is raised to 1300℃. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1225℃. After holding at the temperature for 30 minutes, semi-continuous casting is carried out to produce copper alloy ingots. Step S2, Single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating, and the holding temperature is 850℃ for 4 hours. Then the temperature is raised to 940℃ and held for 4 hours. After that, a single extrusion is performed at an extrusion ratio of 80. After extrusion, the copper alloy rod is cooled by water cooling to obtain copper alloy rod. Step S3, Solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 950℃, and after holding at the temperature for 4 hours, it is cooled by water cooling. Step S4, Continuous extrusion: The copper alloy rod treated in step S3 is subjected to surface oxidation removal, and then continuous extrusion is performed. The extrusion roller is heated to 500℃, the extrusion speed is 15r / min, the number of extrusion passes is 13, the extrusion ratio is 25, and the rod is cooled with a mixture of alcohol and water. Step S5, drawing process: The bar material after step S4 is surface treated, and then cold drawn at a processing rate of 95% to obtain copper alloy wire. Step S6, Online graded continuous annealing treatment: The copper alloy wire obtained in step S5 is placed in an online annealing furnace for graded online continuous annealing treatment to obtain the final copper alloy wire; during the online continuous annealing treatment, the first-stage annealing temperature is controlled at 650℃, the second-stage annealing temperature is controlled at 450℃, and the take-up speed is controlled at 70m / min.

[0037] The microstructure and properties of the ultrafine copper alloy wire were tested after the above-mentioned smelting, casting, extrusion, solution treatment, continuous extrusion, drawing and online graded continuous annealing processes, as shown in Example 3 in Tables 1, 2 and 3. Example 4

[0038] The alloy in this embodiment was smelted using the following raw materials: electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, copper-silicon master alloy, and pure silver. The composition of the alloy is shown in Example 4 of Table 1.

[0039] Step S1, Batching and Casting: Before smelting, electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, copper-silicon master alloy and pure silver are added to a vacuum induction furnace. The temperature is raised to 1300℃. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1200℃. After holding at the temperature for 30 minutes, semi-continuous casting is carried out to obtain copper alloy ingots. Step S2, Single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating, and the holding temperature is 875℃ for 4 hours. Then the temperature is raised to 940℃ and held for 6 hours. After that, a single extrusion is performed at an extrusion ratio of 70. After extrusion, the copper alloy rod is cooled by water cooling to obtain copper alloy rod. Step S3, Solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 1000℃, the holding time is 4h, and then it is cooled by water cooling. Step S4, Continuous extrusion: The copper alloy rod treated in step S3 is subjected to surface oxidation removal, and then continuous extrusion is performed. The extrusion roller is heated to 500℃, the extrusion speed is 20r / min, the number of extrusion passes is 14, the extrusion ratio is 30, and the rod is cooled with a mixture of alcohol and water. Step S5, drawing process: The bar material after step S4 is surface treated, and then cold drawn at a processing rate of 97% to obtain copper alloy wire. Step S6, Online graded continuous annealing treatment: The copper alloy wire obtained in step S5 is placed in an online annealing furnace for graded online continuous annealing treatment to obtain the final copper alloy wire; during the online continuous annealing treatment, the first-stage annealing temperature is controlled at 650℃, the second-stage annealing temperature is controlled at 500℃, and the take-up speed is controlled at 90m / min.

[0040] The microstructure and properties of the ultrafine copper alloy wire were tested after the above-mentioned smelting, casting, extrusion, solution treatment, continuous extrusion, drawing and online graded continuous annealing processes, as shown in Example 4 in Tables 1, 2 and 3. Example 5

[0041] The alloy in this embodiment was smelted using the following raw materials: electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, copper-silicon master alloy, and pure magnesium. The composition of the alloy is shown in Example 5 of Table 1.

[0042] Step S1, Batching and Casting: Before smelting, electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, copper-silicon master alloy and pure magnesium are added to a vacuum induction furnace. The temperature is raised to 1300℃. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1250℃. After holding at the temperature for 30 minutes, semi-continuous casting is carried out to obtain copper alloy ingots. Step S2, Single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating, and the holding temperature is 900℃ for 4 hours. Then the temperature is raised to 950℃ and held for 6 hours. After that, a single extrusion is performed at an extrusion ratio of 90. After extrusion, the copper alloy rod is cooled by water cooling to obtain copper alloy rod. Step S3, Solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 950℃, and after holding at the temperature for 4 hours, it is cooled by water cooling. Step S4, Continuous extrusion: The copper alloy rod treated in step S3 is subjected to surface oxidation removal, and then continuous extrusion is performed. The extrusion roller heating temperature is 525℃, the extrusion speed is 20r / min, the extrusion passes are 12, the extrusion ratio is 20, and the rod is cooled with a mixture of alcohol and water. Step S5, drawing process: The bar material after step S4 is surface treated, and then cold drawn at a processing rate of 95% to obtain copper alloy wire. Step S6, Online graded continuous annealing treatment: The copper alloy wire obtained in step S5 is placed in an online annealing furnace for graded online continuous annealing treatment to obtain the final copper alloy wire; during the online continuous annealing treatment, the first-stage annealing temperature is controlled at 600℃, the second-stage annealing temperature is controlled at 500℃, and the take-up speed is controlled at 100m / min.

[0043] The microstructure and properties of the ultrafine copper alloy wire were tested after the above-mentioned smelting, casting, extrusion, solution treatment, continuous extrusion, drawing and online graded continuous annealing processes, as shown in Example 5 in Tables 1, 2 and 3. Example 6

[0044] The alloy in this embodiment was smelted using the following raw materials: electrolytic copper, electrolytic nickel, copper-beryllium master alloy, and pure silver. The composition of the alloy is shown in Example 6 of Table 1.

[0045] Step S1, Batching and Casting: Before smelting, electrolytic copper, electrolytic nickel, copper-beryllium master alloy and pure silver are added to a vacuum induction furnace. The temperature is raised to 1300℃. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1250℃. After holding at the temperature for 30 minutes, semi-continuous casting is carried out to obtain copper alloy ingots. Step S2, Single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating, and the holding temperature is 850℃ for 5 hours. Then the temperature is raised to 950℃ and held for 4 hours. After that, a single extrusion is performed at an extrusion ratio of 100. After extrusion, the copper alloy rod is cooled by water cooling to obtain the copper alloy rod. Step S3, Solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 970℃, and after holding at the temperature for 4 hours, it is cooled by water cooling. Step S4, Continuous extrusion: The copper alloy rod treated in step S3 is subjected to surface oxidation removal, and then continuous extrusion is performed. The extrusion roller is heated to 500℃, the extrusion speed is 15r / min, the number of extrusion passes is 13, the extrusion ratio is 25, and the rod is cooled with a mixture of alcohol and water. Step S5, drawing process: The bar material after step S4 is surface treated, and then cold drawn at a processing rate of 97% to obtain copper alloy wire. Step S6, Online graded continuous annealing: The copper alloy wire obtained in step S5 is placed in an online annealing furnace for graded continuous annealing to obtain the final copper alloy wire; during the online continuous annealing process, the first-stage annealing temperature is controlled at 650℃, the second-stage annealing temperature is controlled at 450℃, and the take-up speed is controlled at 120m / min.

[0046] The microstructure and properties of the ultrafine copper alloy wire were tested after the above-mentioned smelting, casting, extrusion, solution treatment, continuous extrusion, drawing and online graded continuous annealing processes, as shown in Example 6 in Tables 1, 2 and 3. Example 7

[0047] The alloy in this embodiment was smelted using the following raw materials: electrolytic copper, electrolytic nickel, copper-beryllium master alloy, and pure silver. The composition of the alloy is shown in Example 7 of Table 1.

[0048] Step S1, Batching and Casting: Before smelting, electrolytic copper, electrolytic nickel, copper-beryllium master alloy and pure silver are added to a vacuum induction furnace. The temperature is raised to 1400℃. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1350℃. After holding at the temperature for 30 minutes, semi-continuous casting is carried out to obtain copper alloy ingots. Step S2, Single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating, and the holding temperature is 900℃ for 4 hours. Then the temperature is raised to 920℃ and held for 4 hours. After that, a single extrusion is performed at an extrusion ratio of 60. After extrusion, the copper alloy rod is cooled by water cooling to obtain copper alloy rod. Step S3, Solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 950℃, and after holding at the temperature for 6 hours, it is cooled by water cooling. Step S4, Continuous extrusion: The copper alloy rod treated in step S3 is subjected to surface oxidation removal, and then continuous extrusion is performed. The extrusion roller is heated to 450℃, the extrusion speed is 20r / min, the number of extrusion passes is 11, the extrusion ratio is 15, and the rod is cooled with a mixture of alcohol and water. Step S5, drawing process: The bar material after step S4 is surface treated, and then cold drawn at a processing rate of 99% to obtain copper alloy wire. Step S6, Online graded continuous annealing treatment: The copper alloy wire obtained in step S5 is placed in an online annealing furnace for graded online continuous annealing treatment to obtain the final copper alloy wire; during the online continuous annealing treatment, the first-stage annealing temperature is controlled at 700℃, the second-stage annealing temperature is controlled at 450℃, and the take-up speed is controlled at 50m / min.

[0049] The microstructure and properties of the ultrafine copper alloy wire were tested after the above-mentioned smelting, casting, extrusion, solution treatment, continuous extrusion, drawing and online graded continuous annealing processes, as shown in Example 7 in Tables 1, 2 and 3. Example 8

[0050] The alloy in this embodiment was smelted using the following raw materials: electrolytic copper, electrolytic nickel, copper-beryllium master alloy, and pure silver. The composition of the alloy is shown in Example 8 of Table 1.

[0051] Step S1, Batching and Casting: Before smelting, electrolytic copper, electrolytic nickel, copper-beryllium master alloy and pure silver are added to a vacuum induction furnace. The temperature is raised to 1350℃. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1300℃. After holding at the temperature for 30 minutes, semi-continuous casting is carried out to obtain copper alloy ingots. Step S2, Single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating, and the holding temperature is 800℃ for 6 hours. Then the temperature is raised to 920℃ and held for 6 hours. After that, a single extrusion is performed at an extrusion ratio of 80. After extrusion, the copper alloy rod is cooled by water cooling to obtain copper alloy rod. Step S3, Solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 1000℃, and after holding at the temperature for 6 hours, it is cooled by water cooling. Step S4, Continuous extrusion: The copper alloy rod treated in step S3 is subjected to surface oxidation removal, followed by continuous extrusion. The extrusion roller is heated to 450℃, the extrusion speed is 20r / min, the extrusion is performed in a single pass, the extrusion ratio is 25, and the rod is cooled with a mixture of alcohol and water. Step S5, drawing process: The bar material after step S4 is surface treated, and then cold drawn at a processing rate of 96% to obtain copper alloy wire. Step S6, Online graded continuous annealing treatment: The copper alloy wire obtained in step S5 is placed in an online annealing furnace for graded online continuous annealing treatment to obtain the final copper alloy wire; during the online continuous annealing treatment, the first-stage annealing temperature is controlled at 640℃, the second-stage annealing temperature is controlled at 470℃, and the take-up speed is controlled at 90m / min.

[0052] The microstructure and properties of the ultrafine copper alloy wire were tested after the above-mentioned smelting, casting, extrusion, solution treatment, continuous extrusion, drawing and online graded continuous annealing processes, as shown in Example 8 in Tables 1, 2 and 3.

[0053] Table 1 Dimensions and composition of ultrafine copper alloy wires in Examples 1-8

[0054] Table 2 Physical properties of ultrafine copper alloy wires in Examples 1-8

[0055] Table 3 Microstructure characteristics of ultrafine copper alloy wires in Examples 1-8

[0056] Therefore, as described above, the method for preparing high-strength, high-plasticity ultrafine copper alloy wire provided by this invention involves melting and casting, extrusion, solution treatment, continuous extrusion, drawing, and online graded continuous annealing of prepared raw materials to obtain copper alloy wires with a diameter of 0.08–0.2 mm. In the specific preparation process, copper alloy wires containing different component contents are obtained by configuring different raw materials and adding different amounts. Furthermore, based on the target component content of the copper alloy wire, parameters such as temperature, time, and speed at each stage are adaptively controlled. The resulting ultrafine alloy copper wire has a maximum tensile strength of 680 MPa, a maximum elongation of 20%, a conductivity of 92% IACS, and a single wire bending count of 5 × 10⁻⁶. 10 Secondly, from the perspective of microstructure characteristics, the precipitation density of precipitates in the 5-20 nm cross-section of copper alloy wire can reach up to 5 × 10⁻⁶. 23 m -3 The average grain size in both the transverse and longitudinal cross-sections can be as low as 0.2 μm and will not exceed 1 μm, thus ensuring that the ultra-fine copper alloy wire with a diameter of no more than 0.2 mm has high strength, high plasticity, high toughness and high conductivity, so that the prepared ultra-fine copper alloy wire can be used in wires, cables and precision connectors in aerospace, 5G communication, medical and new energy vehicles.

[0057] The foregoing has shown and described the basic principles and main features of the present invention and its advantages. It will be apparent to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects. The scope of the present invention is defined by the appended claims rather than the foregoing description, and therefore all changes falling within the meaning and scope of the equivalents of the claims are intended to be included within the present invention.

[0058] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for preparing a high-strength, high-ductility, ultrafine copper alloy wire, characterized in that, Includes the following steps: Step S1: Batching and casting. The prepared raw materials are melted in a vacuum induction furnace and then semi-continuously cast. The melting temperature is 1300℃, and the casting temperature is controlled at 1250℃. After holding at the temperature for 30 minutes, the copper alloy ingot is cast. Step S2, single extrusion: The copper alloy ingot obtained in step S1 is placed in a box furnace for heating. The holding temperature is 900℃ and the holding time is 4h. Then the temperature is raised to 950℃ and held for 6h. After that, a single extrusion is performed at an extrusion ratio of 90. After extrusion, the copper alloy rod is cooled by water to obtain copper alloy rod. Step S3, solution treatment: The copper alloy rod obtained in step S2 is placed in a box annealing furnace for solution treatment. The solution treatment temperature is 950℃, and after holding at the temperature for 4 hours, it is cooled by water cooling. Step S4: Continuous extrusion. The copper alloy rod treated in step S3 is subjected to surface oxidation removal, followed by continuous extrusion. The extrusion roller is heated to 525℃, the extrusion speed is 20r / min, the number of extrusion passes is 12, the extrusion ratio is 20, and the rod is cooled with a mixture of alcohol and water. Step S5: Drawing treatment. The bar material after step S4 is surface treated and then cold-drawn at a processing rate of 95% to obtain copper alloy wire. Step S6: Online graded continuous annealing treatment. The copper alloy wire obtained in step S5 is placed in an online annealing furnace for graded continuous annealing treatment to obtain the final copper alloy wire. During the online continuous annealing process, the first-stage annealing temperature is controlled at 600℃, the second-stage annealing temperature is controlled at 500℃, and the take-up speed is controlled at 100m / min. The ultrafine copper alloy wire is mainly composed of the following raw materials by mass percentage: Cr 0.6%, Zr 0.06%, Mg 0.08% and Si 0.05%, with the remainder being Cu; In step S6, the final copper alloy wire has a precipitate density of 5-20 nm in both the transverse and longitudinal cross-sections, and a precipitate density of 5 × 10⁻⁶. 23 m -3 The average grain size in both the transverse and longitudinal sections is 0.6 μm. The final copper alloy wire in step S6 has a diameter of 0.08 mm.

2. The method for preparing high-strength, high-ductility, ultrafine copper alloy wire according to claim 1, characterized in that: The final copper alloy wire in step S6 has a tensile strength of 590 MPa, a conductivity of 75% IACS, and an elongation of 11%.

3. The method for preparing high-strength, high-ductility, ultrafine copper alloy wire according to claim 1, characterized in that, The specific process of step S1 is as follows: Before melting, electrolytic copper, copper-chromium master alloy, copper-zirconium master alloy, copper-silicon master alloy and pure magnesium are added to a vacuum induction furnace. The temperature is raised to 1300℃. After the melt is completely melted, it is stirred evenly. The casting temperature is controlled at 1250℃. After holding at the temperature for 30 minutes, semi-continuous casting is carried out to obtain copper alloy ingots.

4. The application of the ultrafine copper alloy wire according to claim 1 or the ultrafine copper alloy wire prepared by any one of the preparation methods of 1-3 in wires, cables and precision connectors.

Images