High-strength high-toughness beryllium copper micro-wire and manufacturing method thereof

Abstract

The present application relates to beryllium copper microfilament technical field, specifically to a kind of high-strength high toughness beryllium copper microfilament and its manufacturing method.The application comprises the following steps:S1: primary smelting and extrusion: lanthanum powder, scandium powder, copper-nickel alloy, pure aluminum, beryllium wire smelting extrusion, to obtain first blank;S2: secondary smelting and hot rolling: first blank smelting, slagging, hot rolling into second blank;S3: multiple drawing: after first solid solution, second blank is drawn multiple times, to obtain beryllium copper wire blank;S4: post-processing: beryllium copper wire blank is second solid solution and aging treatment, to obtain high-strength high toughness beryllium copper microfilament.The beneficial effect is: by introducing lanthanum and scandium, the strength and toughness of microfilament are improved by complementary effect, and react with aluminum, slow down the influence of low aluminum solid solubility.At the same time, secondary smelting and multiple drawing treatment further improve the strength of beryllium copper microfilament.

Description

Technical Field

[0001] This invention relates to the field of beryllium copper microwire technology, specifically to a high-strength, high-toughness beryllium copper microwire and its manufacturing method. Background Technology

[0002] Beryllium copper microwires are a high-performance copper alloy material widely used in various high-end fields due to their superior physical and mechanical properties. These applications include advanced weapon systems, computer hardware, fiber optic communication equipment, and sockets connecting integrated circuit boards and printed circuit boards.

[0003] However, existing beryllium copper microwires generally have low strength and toughness, making them prone to breakage and resulting in a short service life. Therefore, this patent innovates on raw material composition, raw material ratio, and manufacturing process steps to develop and prepare high-strength and high-toughness beryllium copper microwires, thereby solving the problems encountered by existing products during use and having significant implications for extending the service life of beryllium copper microwires. Summary of the Invention

[0004] The purpose of this invention is to provide a high-strength, high-toughness beryllium copper microwire and its manufacturing method, so as to solve the problems mentioned in the background art.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0006] A method for manufacturing high-strength, high-toughness beryllium copper microwires includes the following steps:

[0007] S1: Primary melting and extrusion: Lanthanum powder, scandium powder, copper-nickel alloy, pure aluminum, and beryllium wire are mixed and melted in a high-purity argon atmosphere to obtain a primary melt; the primary melt is cast into an ingot and extruded to obtain a first billet with a diameter of 40-50mm;

[0008] S2: Secondary melting and hot rolling: The surface of the first billet is polished, washed with ethanol, dried, and then remelted in a high-purity argon atmosphere. The slag is removed to obtain a secondary melt. The secondary melt is cast into an ingot and hot rolled into a second billet with a diameter of 8-10 mm.

[0009] S3: Multiple drawing: After the second billet is solution-treated once, it is drawn multiple times to obtain a beryllium copper wire billet with a diameter of 0.9-1.2mm;

[0010] S4: Post-processing: The beryllium copper wire blank is subjected to secondary solution treatment and aging treatment to obtain high-strength and high-toughness beryllium copper microwires.

[0011] More optimized: the high-strength and high-toughness beryllium copper microwire raw material contains the following components by mass fraction: 1.8-2.0% beryllium, 2.5-3.0% nickel, 0.15-0.2% aluminum, 0.01-0.02% scandium and 0.02-0.04% lanthanum, with the remainder being copper and non-removable impurities, wherein the mass ratio of lanthanum to scandium is (1.8-2.0):(0.9-1.0).

[0012] In a more optimized manner: In step S1, the specific steps are as follows: A: Lanthanum powder and scandium powder are placed into a copper rod with pre-drilled holes, and the copper sheet is used to seal the opening to obtain a mixed material; B: The mixed material is smelted with copper-nickel alloy, pure aluminum, and beryllium wire in a high-purity argon atmosphere to obtain a primary melt; the primary melt is cast into an ingot and extruded to obtain a first billet with a diameter of 40-50mm.

[0013] In a more optimized manner: In step S1, the process parameters for the first melting are: speed 8-10 kg / min, temperature 1300-1350℃, time 30-50 min, and high-purity argon gas flow rate 20-30 L / min. The process parameters for the first melt casting are: casting temperature 1250-1280℃. The extrusion uses a 1650T horizontal extrusion press, with an extrusion temperature of 750-800℃, an extrusion speed of 3-4 mm / s, and an extrusion ratio of 25-30.

[0014] In a more optimized manner: In step S2, the process parameters for secondary melting are: speed 5-6 kg / min, temperature 1360-1400℃, time 40-50 min, high-purity argon gas flow rate 25-30 L / min, and slag removal 3-4 times during the process; the process parameters for secondary melt casting are: casting temperature 1200-1250℃; and the process parameters for hot rolling are: temperature 800-850℃, speed 100-200 m / min.

[0015] In a more optimized manner: In step S3, the process parameters for the first solution treatment are: temperature 680-700℃, time 90-100min; the process parameters for the multiple drawing processes are: drawing is performed using a 560-type disc drawing machine, including 1-10 drawing passes; wherein, the drawing speed for the 1st-3rd drawing passes is 5-6m / min, the die angle is 5-6°, and the total pass yield is 70-80%; the drawing speed for the 4th-6th drawing passes is 3-4m / min, the die angle is 7-8°, and the total pass yield is 25-50%; the drawing speed for the 7th-10th drawing passes is 1.5-2.5m / min, the die angle is 8-10°, and the total pass yield is 10-20%, with vegetable oil used as a lubricant throughout the process.

[0016] In a more optimized manner: in step S4, the temperature of the secondary solution is 500-560℃, the solution time is 90-100 min, the aging temperature is 320-400℃, the aging time is 1-2 h, and both the solution and aging are carried out in a high-purity argon atmosphere with a gas flow rate of 25-30 L / min.

[0017] In this technical solution, the strength and toughness of beryllium copper microwires are enhanced by jointly introducing the rare earth elements lanthanum and scandium. Simultaneously, impurities are effectively removed and grains are refined through secondary melting and multiple drawing processes with specific parameters, further enhancing the material's mechanical properties. Details are as follows:

[0018] The introduction of 0.15%-0.2% Al by mass allows for the formation of Ni3Al and BeNi precipitates in beryllium copper microwires during aging. The interaction between these two phases is significantly enhanced compared to the formation of a single BeNi phase. Simultaneously, it effectively delays the coarsening of the BeNi phase, thereby improving the aging resistance of the beryllium copper alloy. However, the addition of Al to beryllium copper microwires presents a solid solution problem, leading to a decrease in strength. To address this aluminum solid solution issue, this application further introduces the rare earth elements lanthanum and scandium, along with a synergistic secondary melting and multiple drawing process to further improve the performance of the beryllium copper microwires.

[0019] Firstly, rare earth elements La and Sc can react with Al at high temperatures to generate waste residue. Furthermore, compared to other rare earth elements, the addition of La can effectively reduce the secondary dendrite arm spacing of the microfilaments and promote the formation of equiaxed crystals, resulting in a significant grain refinement strengthening effect. Sc can effectively improve the elongation of beryllium copper microfilaments; however, Sc will precipitate in beryllium copper microfilaments, leading to a decrease in tensile properties. To balance toughness and strength, the mass ratio of lanthanum to scandium is limited to (1.8-2.0):(0.9-1.0) in the design, thus ensuring the strength and toughness of the beryllium copper microfilaments.

[0020] Secondly, the secondary melting process is a homogenization process targeting elemental segregation in the alloy ingot, which can effectively suppress segregation. Polishing before secondary melting is to remove oxide scale. Similarly, slag removal can reduce the influence of impurities.

[0021] Third, multiple drawing processes induce multi-system slip in the beryllium copper microwires. The displacement moves along the slip surface, increasing dislocation density. Furthermore, the interaction between dislocations in different slip systems causes dislocation entanglement, increasing resistance to dislocation movement and resulting in work hardening and increased hardness. The introduction of scandium in this design improves elongation, ensuring the drawability of the multiple drawing processes (up to 10 times). A high number of drawing cycles effectively improves the homogenization and mechanical properties of the beryllium copper microwires. During the drawing process, by limiting the progressively decreasing pass rate and progressively increasing half-die angle, the surface quality of the beryllium copper microwires is ensured, making the drawing process smoother, reducing internal stress, and minimizing wire breakage. Detailed Implementation

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0023] It should be noted that there are no special restrictions on the manufacturers of the raw materials involved in this invention. Exemplary examples include: the vegetable oil lubricant is WILKE Engine Lubriccating oil CLP 220; the lanthanum powder has a purity of 99.9% and is model DK-La-100; the scandium powder has a purity of 99.9% and is model JL-Sc; the copper-nickel alloy is NiCu30 alloy wire; the aluminum has a purity of 99.5% and is model 1A50; and the beryllium wire has a purity of 99.9% and is model HIP-56.

[0024] Example 1: A method for manufacturing high-strength, high-toughness beryllium copper microwires, comprising the following steps:

[0025] S1: Primary melting and extrusion: Lanthanum powder and scandium powder are placed into a copper rod with pre-drilled holes, sealed with copper sheets, and mixed with copper-nickel alloy, pure aluminum, and beryllium wire. The mixture is then melted at 1300℃ for 30 minutes in a high-purity argon atmosphere at a melting rate of 8 kg / min and a high-purity argon gas flow rate of 20 L / min to obtain a primary melt. The melt is then cooled to 1250℃ and poured into a casting mold. Subsequently, a 1650T horizontal extruder is used for extrusion at a temperature of 750℃ and a speed of 3 mm / s. The extrusion ratio of the extruder is 25 to obtain a first billet with a diameter of 40 mm.

[0026] S2: Secondary melting and hot rolling: The surface of the first billet is polished, washed with ethanol, dried, and then melted at 1360℃ for 40 minutes in a high-purity argon atmosphere. The melting speed is controlled at 5 kg / min, the gas flow rate of high-purity argon is 25 L / min, and slag is removed 3 times during the process to obtain a secondary melt. The melt is cooled to 1200℃ and poured into a casting mold. Then, it is hot rolled at 800℃ using a wire rod mill at a rolling speed of 100 m / min to obtain a second billet with a diameter of 8 mm.

[0027] S3: Multiple drawing: The second billet is solution-treated at 680℃ for 90 minutes and water-cooled at 35℃. The solution-treated second billet is then drawn using a 560-type disc drawing machine, including 1-10 drawing passes. Among them, the drawing speed of the first 1-3 draws is 5m / min, the half-die angle is 5°, and the total pass rate is 70%; the drawing speed of the 4-6 draws is 3m / min, the half-die angle is 7°, and the total pass rate is 50%; the drawing speed of the 7-10 draws is 1.5m / min, the half-die angle is 8°, and the total pass rate is 10%. Vegetable oil is used as a lubricant throughout the process to obtain a beryllium copper wire blank with a diameter of 0.9mm.

[0028] S4: Post-treatment: The beryllium copper wire blank was solution-treated at 500℃ for 90 min, then water-cooled at 35℃; aged at 320℃ for 1 h, and air-cooled. Both solution treatment and aging were carried out in a high-purity argon atmosphere with a gas flow rate of 25 L / min. This resulted in high-strength and high-toughness beryllium copper microwires.

[0029] The high-strength, high-toughness beryllium copper microwire raw material contains the following elements by mass fraction: 1.8% beryllium, 2.5% nickel, 0.15% aluminum, 0.02% lanthanum, and 0.01% scandium, with the remainder being copper.

[0030] Example 2: A method for manufacturing high-strength, high-toughness beryllium copper microwires, comprising the following steps:

[0031] S1: Primary melting and extrusion: Lanthanum powder and scandium powder are placed into a copper rod with pre-drilled holes, sealed with copper sheets, and mixed with copper-nickel alloy, pure aluminum, and beryllium wire. The mixture is then melted at 1350℃ for 50 minutes in a high-purity argon atmosphere at a melting rate of 10 kg / min and a high-purity argon gas flow rate of 30 L / min to obtain a primary melt. The melt is then cooled to 1280℃ and poured into a casting mold. Subsequently, a 1650T horizontal extruder is used for extrusion at a temperature of 800℃ and a speed of 4 mm / s. The extrusion ratio of the extruder is 30, resulting in a first billet with a diameter of 50 mm.

[0032] S2: Secondary melting and hot rolling: The surface of the first billet is polished, washed with ethanol, dried, and then melted at 1400℃ for 50 minutes in a high-purity argon atmosphere. The melting speed is controlled at 6 kg / min, the gas flow rate of high-purity argon is 30 L / min, and slag is removed 4 times during the process to obtain a secondary melt. The melt is cooled to 1250℃ and poured into a casting mold. Then, it is hot rolled at 850℃ using a wire rod mill at a rolling speed of 200 m / min to obtain a second billet with a diameter of 10 mm.

[0033] S3: Multiple drawing: The second billet is solution-treated at 700℃ for 100 min, water-cooled at 35℃, and then drawn using a 560-type disc drawing machine, including 1-10 drawing passes; among them, the drawing speed of the first 1-3 draws is 6 m / min, the half-die angle is 6°, and the total pass processing rate is 80%; the drawing speed of the fourth 4-6 draws is 4 m / min, the half-die angle is 8°, and the total pass processing rate is 25%; the drawing speed of the seventh 7-10 draws is 2.5 m / min, the half-die angle is 10°, and the total pass processing rate is 20%. Vegetable oil is used as a lubricant throughout the process to obtain a beryllium copper wire blank with a diameter of 1.2 mm.

[0034] S4: Post-treatment: The beryllium copper wire blank was solution-treated at 560℃ for 100 min, then water-cooled at 35℃; aged at 400℃ for 1 h, and air-cooled. Both solution treatment and aging were carried out in a high-purity argon atmosphere with a gas flow rate of 30 L / min. This resulted in high-strength and high-toughness beryllium copper microwires.

[0035] The high-strength, high-toughness beryllium copper microwire raw material contains the following elements by mass fraction: 2.0% beryllium, 3.0% nickel, 0.2% aluminum, 0.04% lanthanum and 0.02% scandium, with the remainder being copper and non-removable impurities.

[0036] Example 3: A method for manufacturing high-strength, high-toughness beryllium copper microwires, comprising the following steps:

[0037] S1: Primary melting and extrusion: Lanthanum powder and scandium powder are placed into a copper rod with pre-drilled holes, sealed with copper sheets, and mixed with copper-nickel alloy, pure aluminum, and beryllium wire. The mixture is then melted at 1325℃ for 40 minutes in a high-purity argon atmosphere at a melting rate of 9 kg / min and a high-purity argon gas flow rate of 25 L / min to obtain a primary melt. The melt is then cooled to 1260℃ and poured into a casting mold. Subsequently, a 1650T horizontal extruder is used for extrusion at a temperature of 760℃ and a speed of 3.5 mm / s. The extrusion ratio of the extruder is 26, resulting in a first billet with a diameter of 45 mm.

[0038] S2: Secondary melting and hot rolling: The surface of the first billet is polished, washed with ethanol, dried, and then melted at 1370℃ for 45 minutes in a high-purity argon atmosphere. The melting speed is controlled at 5.5 kg / min, the gas flow rate of high-purity argon is 27 L / min, and slag is removed 4 times during the process to obtain a secondary melt. The melt is cooled to 1240℃ and poured into a casting mold. Then, it is hot rolled at 840℃ using a wire rod mill at a rolling speed of 150 m / min to obtain a second billet with a diameter of 9 mm.

[0039] S3: Multiple drawing: The second billet is solution-treated at 690℃ for 95 minutes and water-cooled at 35℃. The solution-treated second billet is then drawn using a 560-type disc drawing machine, including 1-10 drawing passes. Among them, the drawing speed of the first 1-3 draws is 5.5m / min, the half-die angle is 6°, and the total pass rate is 78%; the drawing speed of the 4-6 draws is 3.5m / min, the half-die angle is 8°, and the total pass rate is 40%; the drawing speed of the 7-10 draws is 2.5m / min, the half-die angle is 10°, and the total pass rate is 15%. Vegetable oil is used as a lubricant throughout the process to obtain a beryllium copper wire blank with a diameter of 1.02mm.

[0040] S4: Post-treatment: The beryllium copper wire blank was solution-treated at 550℃ for 95 min, then water-cooled at 35℃; aged at 380℃ for 1 h, and air-cooled. Both solution treatment and aging were carried out in a high-purity argon atmosphere with a gas flow rate of 26 L / min. This resulted in high-strength and high-toughness beryllium copper microwires.

[0041] The high-strength, high-toughness beryllium copper microwire raw material contains the following elements by mass fraction: 1.9% beryllium, 2.6% nickel, 0.16% aluminum, 0.03% lanthanum, and 0.015% scandium, with the remainder being copper and non-removable impurities.

[0042] Comparative Example 1: Compared with Example 1, the high-strength and high-toughness beryllium copper microwire raw material in Comparative Example 1 contains the following components by mass fraction: 1.9% beryllium, 2.6% nickel, 0.16% aluminum, 0.01% scandium, with the remainder being copper and non-removable impurities, and the rest of the process remains unchanged.

[0043] Comparative Example 2: Compared with Example 1, the high-strength and high-toughness beryllium copper microwire raw material described in Comparative Example 2 contains the following components by mass fraction: 1.9% beryllium, 2.6% nickel, 0.16% aluminum, 0.02% lanthanum, with the remainder being copper and non-removable impurities, and the rest of the process remains unchanged.

[0044] Comparative Example 3: Compared with Example 1, the high-strength and high-toughness beryllium copper microwire raw material described in Comparative Example 3 contains the following components by mass fraction: 1.9% beryllium, 2.6% nickel, 0.16% aluminum, 0.02% lanthanum and 0.005% scandium, with the remainder being copper and non-removable impurities. The rest of the process remains unchanged.

[0045] Comparative Example 4: Compared with Example 1, Comparative Example 4 did not undergo secondary smelting or slag removal, but the rest of the process remained unchanged.

[0046] Comparative Example 5: A method for manufacturing high-strength, high-toughness beryllium copper microwires, comprising the following steps:

[0047] S1: Primary melting and extrusion: Lanthanum powder and scandium powder are placed into a copper rod with pre-drilled holes, sealed with copper sheets, and mixed with copper-nickel alloy, pure aluminum, and beryllium wire. The mixture is then melted at 1300℃ for 30 minutes in a high-purity argon atmosphere at a melting rate of 8 kg / min and a high-purity argon gas flow rate of 20 L / min to obtain a primary melt. The melt is then cooled to 1250℃ and poured into a casting mold. Subsequently, a 1650T horizontal extruder is used for extrusion at a temperature of 750℃ and a speed of 3 mm / s. The extrusion ratio of the extruder is 25 to obtain a first billet with a diameter of 40 mm.

[0048] S2: Secondary melting and hot rolling: The surface of the first billet is polished, washed with ethanol, dried, and then melted at 1360℃ for 40 minutes in a high-purity argon atmosphere. The melting speed is controlled at 5 kg / min, the gas flow rate of high-purity argon is 25 L / min, and slag is removed 3 times during the process to obtain a secondary melt. The melt is cooled to 1200℃ and poured into a casting mold. Then, it is hot rolled at 800℃ using a wire rod mill at a rolling speed of 100 m / min to obtain a second billet with a diameter of 8 mm.

[0049] S3: Multiple drawing: The second billet is solution-treated at 680℃ for 90 minutes and water-cooled at 35℃. The solution-treated second billet is then drawn using a 560-type disc drawing machine, including 1-3 drawing passes. The wire drawing speed for the first drawing is 5 m / min, the half-die angle is 5°, and the pass yield is 70%. The wire drawing speed for the second drawing is 3 m / min, the half-die angle is 7°, and the pass yield is 50%. The wire drawing speed for the third drawing is 1.5 m / min, the half-die angle is 8°, and the pass yield is 10%. Vegetable oil is used as a lubricant throughout the process to obtain a beryllium copper wire billet with a diameter of 0.9 mm.

[0050] S4: Post-treatment: The beryllium copper wire blank was solution-treated at 500℃ for 90 min, then water-cooled at 35℃; aged at 320℃ for 1 h, and air-cooled. Both solution treatment and aging were carried out in a high-purity argon atmosphere with a gas flow rate of 25 L / min. This resulted in high-strength and high-toughness beryllium copper microwires.

[0051] The high-strength, high-toughness beryllium copper microwire raw material contains the following elements by mass fraction: 1.8% beryllium, 2.5% nickel, 0.15% aluminum, 0.02% lanthanum, and 0.01% scandium, with the remainder being copper.

[0052] Comparative Example 6: A method for manufacturing high-strength, high-toughness beryllium copper microwires, comprising the following steps:

[0053] S1: Primary melting and extrusion: Lanthanum powder and scandium powder are placed into a copper rod with pre-drilled holes, sealed with copper sheets, and mixed with copper-nickel alloy, pure aluminum, and beryllium wire. The mixture is then melted at 1300℃ for 30 minutes in a high-purity argon atmosphere at a melting rate of 8 kg / min and a high-purity argon gas flow rate of 20 L / min to obtain a primary melt. The melt is then cooled to 1250℃ and poured into a casting mold. Subsequently, a 1650T horizontal extruder is used for extrusion at a temperature of 750℃ and a speed of 3 mm / s. The extrusion ratio of the extruder is 25, resulting in a first billet with a diameter of 40 mm.

[0054] S2: Secondary melting and hot rolling: The surface of the first billet is polished, washed with ethanol, dried, and then melted at 1360℃ for 40 minutes in a high-purity argon atmosphere. The melting speed is controlled at 5 kg / min, the gas flow rate of high-purity argon is 25 L / min, and slag is removed 3 times during the process to obtain a secondary melt. The melt is cooled to 1200℃ and poured into a casting mold. Then, it is hot rolled at 800℃ using a wire rod mill at a rolling speed of 100 m / min to obtain a second billet with a diameter of 8 mm.

[0055] S3: Multiple drawing: The second billet is solution-treated at 680℃ for 90 minutes and water-cooled at 35℃. The solution-treated second billet is then drawn using a 560-type disc drawing machine, including 1-10 drawing passes. Among them, the drawing speed of the first 1-3 draws is 5m / min, the half-die angle is 8°, and the total pass processing rate is 70%; the drawing speed of the 4-6 draws is 3m / min, the half-die angle is 7°, and the total pass processing rate is 50%; the drawing speed of the 7-10 draws is 1.5m / min, the half-die angle is 5°, and the total pass processing rate is 10%. Vegetable oil is used as a lubricant throughout the process to obtain a beryllium copper wire blank with a diameter of 0.9mm.

[0056] S4: Post-treatment: The beryllium copper wire blank was solution-treated at 500℃ for 90 min, then water-cooled at 35℃; aged at 320℃ for 1 h, and air-cooled. Both solution treatment and aging were carried out in a high-purity argon atmosphere with a gas flow rate of 25 L / min. This resulted in high-strength and high-toughness beryllium copper microwires.

[0057] The high-strength, high-toughness beryllium copper microwire raw material contains the following elements by mass fraction: 1.8% beryllium, 2.5% nickel, 0.15% aluminum, 0.02% lanthanum, and 0.01% scandium, with the remainder being copper.

[0058] Test Experiment 1: The tensile strength of the beryllium copper microwires prepared in the examples and comparative examples was tested at 25°C at a speed of 1 mm / min. The test data are shown in Table 1.

[0059]

[0060]

[0061] Table 1

[0062] Test Experiment 2: The elongation of the beryllium copper microwires prepared in the examples and comparative examples was measured according to GB / T228-2002. The elongation also reflects the toughness of the material. The test data are shown in Table 2.

[0063]

[0064] Table 2

[0065] Conclusion: The above data show that in Comparative Example 1, the absence of the rare earth element lanthanum resulted in a decrease in the strength of the beryllium copper microwires, while the elongation was similar to that of Example 1. In Comparative Example 2, the absence of the rare earth element scandium resulted in a similar strength to that of Example 1, but a decrease in elongation. Scandium has low solubility in beryllium copper and exists as a precipitated phase, thus increasing its elongation. Lanthanum effectively reduces the secondary dendrite arm spacing of the beryllium copper microwires and promotes the formation of equiaxed crystals, producing a significant grain-refining strengthening effect and enhancing the strength of the beryllium copper microwires. Therefore, the simultaneous addition of both can enhance both the strength and toughness of the beryllium copper microwires.

[0066] In Comparative Example 3, the reduced amounts of lanthanum and scandium resulted in decreased tensile strength and elongation. This is because insufficient lanthanum and scandium prevented the formation of slag with aluminum, leaving some Al elements dissolved in the copper matrix, thus reducing the strength of the beryllium copper microwire. Furthermore, the reduced amounts of lanthanum and scandium significantly weakened their impact on the material. Comparative Example 4 omitted secondary smelting and slag removal, leading to performance degradation. Comparative Example 5 only underwent three drawing operations, which was insufficient, resulting in performance decline. In Comparative Example 6, the decreasing half-die angle during drawing reduced the surface quality and overall performance of the beryllium copper microwire.

[0067] Examples 1-3 rationally introduce elements such as lanthanum and scandium, which not only react with aluminum to form residues and reduce the impact of impurities, but also complement each other, improving both strength and toughness compared to traditional methods. Furthermore, through secondary melting and appropriate drawing processes, the strength and toughness of beryllium copper microwires are effectively enhanced.

[0068] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for manufacturing high-strength, high-toughness beryllium copper microwires, characterized in that: Includes the following steps: S1: Primary melting and extrusion: Lanthanum powder, scandium powder, copper-nickel alloy, pure aluminum, and beryllium wire are mixed and melted in a high-purity argon atmosphere to obtain a primary melt; the primary melt is cast into an ingot and extruded to obtain a first billet with a diameter of 40-50mm; S2: Secondary melting and hot rolling: The surface of the first billet is polished, washed with ethanol, dried, and then remelted in a high-purity argon atmosphere. The slag is removed to obtain a secondary melt. The secondary melt is cast into an ingot and hot rolled into a second billet with a diameter of 8-10 mm. S3: Multiple drawing: After the second billet is solution-treated once, it is drawn multiple times to obtain a beryllium copper wire billet with a diameter of 0.9-1.2mm; S4: Post-processing: The beryllium copper wire blank is subjected to secondary solution treatment and aging treatment to obtain high-strength and high-toughness beryllium copper microwires; The high-strength, high-toughness beryllium copper microwire raw material comprises the following components by mass fraction: 1.8-2.0% beryllium, 2.5-3.0% nickel, 0.15-0.2% aluminum, 0.03-0.06% rare earth elements, and the remainder being copper; The rare earth elements are lanthanum and scandium in a mass ratio of (1.8-2.0):(0.9-1.0); In step S3, the process parameters for the first solution treatment are: temperature 680-700℃, time 90-100min; the process parameters for the multiple drawing processes are: drawing is performed using a 560-type disc drawing machine, including 10 drawing passes; among them, the drawing speed for the first 1-3 draws is 5-6m / min, the die angle is 5-6°, and the total pass yield is 70-80%; the drawing speed for the 4-6 draws is 3-4m / min, the die angle is 7-8°, and the total pass yield is 25-50%; the drawing speed for the 7-10 draws is 1.5-2.5m / min, the die angle is 8-10°, and the total pass yield is 10-20%, with vegetable oil used as a lubricant throughout the process.

2. The method for manufacturing a high-strength, high-toughness beryllium copper microwire according to claim 1, characterized in that: In step S1, the specific steps are as follows: A: Lanthanum powder and scandium powder are placed into a copper rod with pre-drilled holes, and the copper sheet is used to seal the opening to obtain a mixed material; B: The mixed materials, copper-nickel alloy, pure aluminum, and beryllium wire are smelted in a high-purity argon atmosphere to obtain a primary melt; the primary melt is cast into an ingot and extruded to obtain a first billet with a diameter of 40-50mm.

3. The method for manufacturing a high-strength, high-toughness beryllium copper microwire according to claim 1, characterized in that: In step S1, the process parameters for one melting are: speed of 8-10 kg / min, temperature of 1300-1350℃, time of 30-50 min, and high-purity argon gas flow rate of 20-30 L / min.

4. The method for manufacturing a high-strength, high-toughness beryllium copper microwire according to claim 1, characterized in that: In step S1, the process parameters for the primary melt casting ingot are: casting temperature of 1250-1280℃; extrusion is carried out using a 1650T horizontal extrusion press, extrusion temperature of 750-800℃, extrusion speed of 3-4mm / s, and extrusion ratio of 25-30.

5. The method for manufacturing a high-strength, high-toughness beryllium copper microwire according to claim 1, characterized in that: In step S2, the process parameters for secondary melting are: speed 5-6 kg / min, temperature 1360-1400℃, time 40-50 min, high-purity argon gas flow rate 25-30 L / min, and slag removal 3-4 times during the process; the process parameters for secondary melt casting are: casting temperature 1200-1250℃; and the process parameters for hot rolling are: temperature 800-850℃, speed 100-200 m / min.

6. The method for manufacturing a high-strength, high-toughness beryllium copper microwire according to claim 1, characterized in that: In step S4, the temperature for the second solution is 500-560℃ and the time is 90-100 min. The aging temperature is 320-400℃ and the aging time is 1-2 h. Both the solution and aging are carried out in a high-purity argon atmosphere with a gas flow rate of 25-30 L / min.

7. The high-strength, high-toughness beryllium copper microwire obtained by the manufacturing method of a high-strength, high-toughness beryllium copper microwire according to any one of claims 1-6.

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