A high-strength tungsten alloy wire and its preparation method

Abstract

The present invention belongs to the technical field of powder metallurgy, and particularly relates to a high-strength tungsten alloy wire and a preparation method thereof. By means of the method of ball milling and mixing in coordination with microwave sintering, the doping of lanthanum oxide is made uniform. By coordinating the logarithmic strain of the rotary hammer, the annealing process, etc., the recrystallization temperature of tungsten grains is reduced, and the tungsten grains grow uniformly, thereby improving the plasticity of the tungsten wire, and a high-strength tungsten alloy wire is prepared. The wire diameter of the high-strength tungsten alloy wire is less than 30 μm, the tensile strength is ≥6200 MPa, and the qualification rate is ≥80%.

Description

Technical Field

[0001] The present invention belongs to the technical field of powder metallurgy, and particularly relates to a high-strength tungsten alloy wire and a preparation method thereof. Background Art

[0002] Low-strength tungsten wires are extremely prone to wire breakage during the drawing process, which affects the continuous production of drawing and reduces the qualified rate of products. At present, doping lanthanum oxide is an effective measure to improve the strength of tungsten wires. However, lanthanum oxide is difficult to be uniformly dispersed in the tungsten matrix and is prone to lanthanum oxide coarsening, resulting in frequent wire breakage during the drawing process of tungsten wires. The doping and sintering processes are the key factors affecting the uniformity of lanthanum oxide.

[0003] In addition, with the advancement of the thinning process of silicon wafers, the trend of tungsten wire thinning has become more and more obvious. However, when using traditional processes to prepare tungsten wires, the wire breakage rate increases significantly with the decrease of the wire diameter. Especially after the wire diameter is less than 30 μm, the qualified rate of wire materials decreases significantly. It is found that the limit wire diameter of tungsten wires is restricted by their plasticity, and the plasticity of tungsten wires is mainly affected by the tungsten grain size. The annealing process is an important means to control the tungsten grain size. By annealing, the tungsten grain size can be effectively increased, thereby improving the plasticity of tungsten wires. However, the traditional annealing process has problems such as a relatively high recrystallization temperature and uneven tungsten grain size. Therefore, the production of high-strength ultra-fine tungsten alloy wires is still a huge challenge. Summary of the Invention

[0004] To solve the problems existing in the prior art, the main object of the present invention is to propose a high-strength tungsten alloy wire and a preparation method thereof.

[0005] According to the first aspect of the present invention, the following technical solutions are provided:

[0006] A preparation method of a high-strength tungsten alloy wire, comprising the following steps:

[0007] S1. Adding tungsten powder, lanthanum oxide, and grinding balls into a ball mill can to perform ball milling to obtain a mixed powder;

[0008] S2. Loading the mixed powder into a mold for isostatic pressing to obtain a tungsten green body;

[0009] S3. Placing the tungsten green body into a microwave oven for sintering to obtain a tungsten blank;

[0010] S4. Heating the tungsten blank and then performing rolling to obtain a tungsten rod 1;

[0011] S5. Annealing the tungsten rod 1 to obtain a tungsten rod 2;

[0012] S6. Forging the tungsten rod 2 to obtain a tungsten rod 1;

[0013] S7. Annealing the tungsten rod 1 to obtain a tungsten rod 2;

[0014] S8. Draw the tungsten rod 2 to obtain a high-strength tungsten alloy wire.

[0015] According to the second aspect of the present invention, the present invention provides the following technical solution:

[0016] A high-strength tungsten alloy wire is prepared by using the preparation method of the above-mentioned high-strength tungsten alloy wire. The wire diameter of the high-strength tungsten alloy wire is less than 30 μm, the tensile strength is ≥ 6200 MPa, and the qualified rate is ≥ 80%.

[0017] The beneficial effects of the present invention are as follows:

[0018] The present invention provides a high-strength tungsten alloy wire and a preparation method thereof. Through the method of ball milling and mixing in coordination with microwave sintering, the lanthanum oxide doping is made uniform. By coordinating the logarithmic strain of the rotary hammer, the annealing process, etc., the recrystallization temperature of the tungsten grains is reduced, and the tungsten grains grow uniformly, thereby improving the plasticity of the tungsten wire. A high-strength tungsten alloy wire is prepared. The wire diameter of the high-strength tungsten alloy wire is less than 30 μm, the tensile strength is ≥ 6200 MPa, and the qualified rate is ≥ 80%. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts.

[0020] Figure 1 It is the metallographic diagram of the tungsten rod 2 prepared in Example 1 of the present invention;

[0021] Figure 2 It is the metallographic diagram of the tungsten rod 2 prepared in Comparative Example 2 of the present invention;

[0022] Figure 3 It is the metallographic diagram of the tungsten rod 2 prepared in Comparative Example 5 of the present invention;

[0023] Figure 4 It is the metallographic diagram of the tungsten rod 2 prepared in Comparative Example 6 of the present invention.

[0024] The realization, functional features and advantages of the object of the present invention will be further described in conjunction with the embodiments with reference to the drawings. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The technical solutions in the embodiments will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0026] According to the first aspect of the present invention, the following technical solutions are provided:

[0027] A method for preparing a high-strength tungsten alloy wire, comprising the following steps:

[0028] S1. Add tungsten powder, lanthanum oxide, and grinding balls into a ball mill tank for ball milling to obtain a mixed powder;

[0029] S2. Load the mixed powder into a mold for isostatic pressing to obtain a tungsten green body;

[0030] S3. Put the tungsten green body into a microwave oven for sintering to obtain a tungsten blank;

[0031] S4. Heat the tungsten blank and then perform rolling to obtain tungsten rod 1;

[0032] S5. Anneal tungsten rod 1 to obtain tungsten rod 2;

[0033] S6. Forge tungsten rod 2 to obtain tungsten rod 1;

[0034] S7. Anneal tungsten rod 1 to obtain tungsten rod 2;

[0035] S8. Draw tungsten rod 2 to obtain a high-strength tungsten alloy wire.

[0036] Through the coordinated ball milling and mixing and microwave sintering processes, the present invention effectively reduces the agglomeration phenomenon of lanthanum oxide, reduces the wire breakage rate during the drawing process, and improves the tensile strength and qualification rate of the tungsten wire. By coordinately regulating the logarithmic strain of the rotary hammer, the annealing time, and the annealing temperature, the recrystallization temperature of tungsten grains is reduced, and the tungsten grains grow uniformly, thereby improving the plasticity of the tungsten wire.

[0037] Preferably, in the step S1, the mass fraction of lanthanum oxide in the mixed powder is 0.65 - 0.75 wt%; the grinding balls are agate ball mill beads, the mass ratio of the mixed powder to the grinding balls is (8 - 10):1, the diameter of the grinding balls is 3.5 - 4.0 mm, the ball mill rotation speed is 240 - 250 rpm, and the ball milling time is 3 - 3.5 h. Specifically, the mass fraction of lanthanum oxide in the mixed powder can be, for example, any one of 0.65 wt%, 0.66 wt%, 0.67 wt%, 0.68 wt%, 0.69 wt%, 0.70 wt%, 0.71 wt%, 0.72 wt%, 0.73 wt%, 0.74 wt%, 0.75 wt% or the range between any two of them; the mass ratio of the mixed powder to the grinding balls can be, for example, any one of 8:1, 8.5:1, 9:1, 9.5:1, 10:1 or the range between any two of them; the ball mill rotation speed can be, for example, any one of 240 rpm, 241 rpm, 242 rpm, 243 rpm, 244 rpm, 245 rpm, 246 rpm, 247 rpm, 248 rpm, 249 rpm, 250 rpm or the range between any two of them; the ball milling time can be, for example, any one of 3 h, 3.25 h, 3.5 h or the range between any two of them.

[0038] Preferably, in the step S2, the isostatic pressure is 120 - 130 MPa. Specifically, the isostatic pressure can be, for example, any one of 120 MPa, 121 MPa, 122 MPa, 123 MPa, 124 MPa, 125 MPa, 126 MPa, 127 MPa, 128 MPa, 129 MPa, 130 MPa or the range between any two of them.

[0039] Preferably, in the step S3, the green tungsten blank is placed in the cylinder of the microwave oven and sintered in an atmosphere of H2 + N2 with a H2 volume fraction of 5 vol% to obtain a tungsten blank with a diameter of 18.5 ± 0.3 mm, where the cylinder rotates at a speed of 5 rpm (to ensure uniform heating of the green tungsten blank), the sintering temperature is 1600 - 1850 °C, and the sintering time is 20 - 25 min. Specifically, the sintering temperature can be, for example, any one of 1600 °C, 1650 °C, 1700 °C, 1750 °C, 1800 °C, 1850 °C or the range between any two of them, and the sintering time can be, for example, any one of 20 min, 21 min, 22 min, 23 min, 24 min, 25 min or the range between any two of them.

[0040] Preferably, in the step S4, the tungsten billet is heated to 1700-1800 °C for rolling to obtain a tungsten rod 1 with a diameter of 9±0.5 mm. Specifically, the heating temperature of the tungsten billet can be, for example, any one of 1700 °C, 1710 °C, 1720 °C, 1730 °C, 1740 °C, 1750 °C, 1760 °C, 1770 °C, 1780 °C, 1790 °C, 1800 °C or the range between any two of them.

[0041] Preferably, in the step S5, the tungsten rod 1 is annealed to reduce the internal stress of the tungsten rod, wherein the annealing temperature is 2100-2300 °C, the tungsten rod 1 moves along its axial direction during annealing, and the annealing speed is 0.25-0.35 m / min to obtain a tungsten rod 2. Specifically, the annealing temperature can be, for example, any one of 2100 °C, 2150 °C, 2200 °C, 2250 °C, 2300 °C or the range between any two of them, and the annealing speed can be, for example, any one of 0.25 m / min, 0.26 m / min, 0.27 m / min, 0.28 m / min, 0.29 m / min, 0.30 m / min, 0.31 m / min, 0.32 m / min, 0.33 m / min, 0.34 m / min, 0.35 m / min or the range between any two of them.

[0042] Preferably, in the step S6, the tungsten rod 2 is swaged to obtain a tungsten rod 1, and its logarithmic strain is 0.95-1.30 (the annealing recrystallization temperature of the tungsten rod 1 with different logarithmic strains is different). The logarithmic strain ε = ln(S0 / S n ), S0 is the cross-sectional area of the tungsten rod 2, and S n is the cross-sectional area of the tungsten rod 1 obtained after swaging the tungsten rod 2. Specifically, the logarithmic strain can be, for example, any one of 0.95, 1.00, 1.05, 1.10, 1.15, 1.20, 1.25, 1.30 or the range between any two of them.

[0043] Preferably, in step S7, the annealing temperature is 2400~2500°C. During annealing, the tungsten rod 1 moves along its axial direction, and the annealing speed is 0.35~0.50 m / min. Specifically, the annealing temperature can be, for example, any one of 2400°C, 2410°C, 2420°C, 2430°C, 2440°C, 2450°C, 2460°C, 2470°C, 2480°C, 2490°C, 2500°C or the range between any two of them, and the annealing speed can be, for example, any one of 0.35 m / min, 0.36 m / min, 0.37 m / min, 0.38 m / min, 0.39 m / min, 0.40 m / min, 0.41 m / min, 0.42 m / min, 0.43 m / min, 0.44 m / min, 0.45 m / min, 0.46 m / min, 0.47 m / min, 0.48 m / min, 0.49 m / min, 0.50 m / min or the range between any two of them. Further preferably, the tungsten grain structure of the tungsten rod 2 is uniform, the average particle size of the tungsten grains is 35~40 μm, and the hardness HV30 of the tungsten rod 2 is 385~410.

[0044] According to the second aspect of the present invention, the present invention provides the following technical solution:

[0045] A high-strength tungsten alloy wire is prepared by using the preparation method of the high-strength tungsten alloy wire described above. The wire diameter of the high-strength tungsten alloy wire is less than 30 μm, the tensile strength ≥ 6200 MPa, and the qualified rate ≥ 80% (the length of continuous wire drawing without break for a single time greater than 160 km is regarded as qualified).

[0046] Preferably, the high-strength tungsten alloy wire is a tungsten wire with a wire diameter of 28 μm, the tensile strength > 6200 MPa, and the qualified rate > 80%;

[0047] Preferably, the high-strength tungsten alloy wire is a tungsten wire with a wire diameter of 25 μm, the tensile strength > 6400 MPa, and the qualified rate > 80%;

[0048] Preferably, the high-strength tungsten alloy wire is a tungsten wire with a wire diameter of 22 μm, the tensile strength > 6550 MPa, and the qualified rate > 80%;

[0049] The technical solution of the present invention will be further described below in conjunction with specific embodiments.

[0050] Example 1

[0051] A preparation method of a high-strength tungsten alloy wire includes the following steps:

[0052] S1. Add tungsten powder, lanthanum oxide, and grinding balls into a ball mill jar for ball milling to obtain a mixed powder. The mass fraction of lanthanum oxide in the mixed powder is 0.70 wt%. The grinding balls are agate ball mill beads. The mass ratio of the mixed powder to the grinding balls is 8:1. The diameter of the grinding balls is 3.5 mm. The ball milling speed is 240 rpm, and the ball milling time is 3 h.

[0053] S2. Load the mixed powder into a mold for isostatic pressing to obtain a tungsten green body. The isostatic pressing pressure is 120 MPa.

[0054] S3. Place the tungsten green body into a cylinder of a microwave oven and sinter it in an atmosphere of H2 + N2 with a H2 volume fraction of 5 vol% to prepare a tungsten blank with a diameter of 18.5 ± 0.3 mm. The cylinder rotates at a speed of 5 rpm. The sintering temperature is 1800 °C, and the sintering time is 20 min.

[0055] S4. Heat the tungsten blank to 1700 °C for rolling to obtain a tungsten rod 1 with a diameter of 9 ± 0.5 mm.

[0056] S5. Anneal the tungsten rod 1. The annealing temperature is 2250 °C, and the annealing speed is 0.30 m / min to obtain a tungsten rod 2.

[0057] S6. Forge the tungsten rod 2 using a rotary hammer to obtain a tungsten rod 1 with a logarithmic strain of 1.15.

[0058] S7. Anneal the tungsten rod 1. The annealing temperature is 2400 °C, and the annealing speed is 0.45 m / min to obtain a tungsten rod 2 (as shown). The tungsten grain structure of the tungsten rod 2 is uniform. The average grain diameter of the tungsten grains is 38 μm. The hardness HV30 of the tungsten rod 2 is 392. Figure 1 shown). The tungsten grain structure of the tungsten rod 2 is uniform. The average grain diameter of the tungsten grains is 38 μm. The hardness HV30 of the tungsten rod 2 is 392.

[0059] S8. Draw the tungsten rod 2 to prepare tungsten wires of type 28. A total of 20 rolls of tungsten wires are produced. The average tensile strength is 6324 MPa, the range is 84 MPa, the ratio of the range to the average value is 1.33%, and 17 rolls have a length greater than 160 km. The qualified rate is 85%.

[0060] Example 2

[0061] A method for preparing a high-strength tungsten alloy wire, comprising the following steps:

[0062] S1. Add tungsten powder, lanthanum oxide, and grinding balls into a ball mill jar for ball milling to obtain a mixed powder. The mass fraction of lanthanum oxide in the mixed powder is 0.75 wt%. The grinding balls are agate ball mill beads. The mass ratio of the mixed powder to the grinding balls is 10:1. The diameter of the grinding balls is 4.0 mm. The ball milling speed is 240 rpm, and the ball milling time is 3 h.

[0063] S2. Load the mixed powder into a mold and perform isostatic pressing to obtain a tungsten green compact; the isostatic pressure is 130 MPa;

[0064] S3. Place the tungsten green compact into the cylinder of a microwave oven and sinter it in an H2+N2 atmosphere with an H2 volume fraction of 5 vol% to obtain a tungsten blank with a diameter of 18.5±0.3 mm. The cylinder rotates at a speed of 5 rpm, the sintering temperature is 1750 °C, and the sintering time is 25 min;

[0065] S4. Heat the tungsten blank to 1800 °C and roll it to obtain a tungsten rod 1 with a diameter of 9±0.5 mm;

[0066] S5. Anneal the tungsten rod 1, where the annealing temperature is 2200 °C and the annealing speed is 0.30 m / min to obtain a tungsten rod 2;

[0067] S6. Forge the tungsten rod 2 using a rotary hammer to obtain a tungsten rod 1, with a logarithmic strain of 1.24;

[0068] S7. Anneal the tungsten rod 1, with an annealing temperature of 2450 °C and an annealing speed of 0.35 m / min to obtain a tungsten rod 2; the tungsten grain structure of the tungsten rod 2 is uniform, the average grain size of the tungsten grains is 36 μm, and the hardness HV30 of the tungsten rod 2 is 400;

[0069] S8. Draw the tungsten rod 2 to prepare 25-type tungsten wire. A total of 19 rolls of tungsten wire are produced, with an average tensile strength of 6490 MPa, a range of 75 MPa, and the ratio of the range to the average value is 1.16%. Among them, 16 rolls have a length greater than 160 km, and the qualified rate is 84%.

[0070] Example 3

[0071] A method for preparing a high-strength tungsten alloy wire, comprising the following steps:

[0072] S1. Add tungsten powder, lanthanum oxide, and grinding balls to a ball mill tank and perform ball milling to obtain a mixed powder; the mass fraction of lanthanum oxide in the mixed powder is 0.65 wt%; the grinding balls are agate ball mill beads, the mass ratio of the mixed powder to the grinding balls is 8:1, the diameter of the grinding balls is 3.5 mm, the ball milling speed is 250 rpm, and the ball milling time is 3.5 h;

[0073] S2. Load the mixed powder into a mold and perform isostatic pressing to obtain a tungsten green compact; the isostatic pressure is 130 MPa;

[0074] S3. Place the tungsten green compact into the cylinder of a microwave oven and sinter it in an H2+N2 atmosphere with an H2 volume fraction of 5 vol% to obtain a tungsten blank with a diameter of 18.5±0.3 mm. The cylinder rotates at a speed of 5 rpm, the sintering temperature is 1700 °C, and the sintering time is 20 min;

[0075] S4. Heat the tungsten billet to 1750 °C and roll it to obtain a tungsten rod 1 with a diameter of 9 ± 0.5 mm;

[0076] S5. Anneal the tungsten rod 1, where the annealing temperature is 2200 °C and the annealing speed is 0.35 m / min to obtain a tungsten rod 2;

[0077] S6. Forge the tungsten rod 2 using a rotary hammer to obtain a tungsten rod 1 with a logarithmic strain of 0.95;

[0078] S7. Anneal the tungsten rod 1 at an annealing temperature of 2400 °C and an annealing speed of 0.50 m / min to obtain a tungsten rod 2; The tungsten grain structure of the tungsten rod 2 is uniform, the average particle size of the tungsten grains is 40 μm, and the hardness HV30 of the tungsten rod 2 is 398;

[0079] S8. Draw the tungsten rod 2 to prepare a tungsten wire of type 22. A total of 20 coils of tungsten wire are produced, with an average tensile strength of 6610 MPa, a range of 43 MPa, and the ratio of the range to the average value is 0.65%. Among them, 17 coils have a length greater than 160 km, and the qualification rate is 85%.

[0080] Comparative Example 1

[0081] The difference from Example 1 is that according to the traditional production process, a tungsten alloy wire with a wire diameter of 28 μm is prepared. Specifically: mix tungsten powder and lanthanum oxide using a high-energy mixer, sinter and hot-roll using the intermediate-frequency sintering method to obtain a tungsten rod, and the logarithmic strain during rotary forging is 0.75.

[0082] The tungsten grains of the tungsten rod 2 prepared in this comparative example are uneven in size, and the hardness fluctuates greatly. A total of 20 coils of tungsten wire are produced, with an average tensile strength of 5546 MPa, a range of 152 MPa, and the ratio of the range to the average value is 2.74%. Among them, 11 coils have a length greater than 160 km, and the qualification rate is 55%.

[0083] Comparative Example 2

[0084] The difference from Example 1 is that in step S1, tungsten powder and lanthanum oxide are added to a high-energy powder mixer in the proportion of Example 1 for mixing.

[0085] The tungsten grains of the tungsten rod 2 (as shown in Figure 2 ) prepared in this comparative example are uneven in size, and the hardness fluctuates greatly. A total of 20 coils of tungsten wire are produced, with an average tensile strength of 5752 MPa, a range of 127 MPa, and the ratio of the range to the average value is 2.21%. Among them, 13 coils have a length greater than 160 km, and the qualification rate is 65%.

[0086] Comparative Example 3

[0087] The difference from Example 1 is that in step S3, the cylinder of the microwave oven does not rotate.

[0088] For the tungsten rod 2 prepared in this comparative example, the tungsten grain sizes are uneven, and the hardness fluctuates greatly. A total of 20 coils of tungsten wire were produced. The average tensile strength was 5960 MPa, the range was 96 MPa, the ratio of the range to the average value was 1.61%, 13 coils had a length greater than 160 km, and the qualified rate was 65%.

[0089] Comparative Example 4

[0090] The difference from Example 1 is that step S5 is not carried out.

[0091] During the forging process of this comparative example, the tungsten rod cracked severely and could not be deformed further.

[0092] Comparative Example 5

[0093] The difference from Example 1 is that in step S6, the logarithmic strain is 1.54.

[0094] For the tungsten rod 2 prepared in this comparative example (as Figure 3 shown), the tungsten grains are on the small side, HV30 is 448. A total of 20 coils of tungsten wire were produced. The average tensile strength was 6443 MPa, the range was 58 MPa, the ratio of the range to the average value was 0.90%, 7 coils had a length greater than 160 km, and the qualified rate was 35%.

[0095] Comparative Example 6

[0096] The difference from Example 1 is that in step S7, the annealing temperature is 2700 °C.

[0097] For the tungsten rod 2 prepared in this comparative example (as Figure 4 shown), the tungsten grains are on the large side, HV30 is 356. A total of 20 coils of tungsten wire were produced. The average tensile strength was 5068 MPa, the range was 86 MPa, the ratio of the range to the average value was 1.70%, 11 coils had a length greater than 160 km, and the qualified rate was 55%.

[0098] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention accordingly. Any equivalent structural transformation made using the content of the specification of the present invention under the inventive concept of the present invention, or any direct / indirect application in other related technical fields, is included in the patent protection scope of the present invention.

Claims

1. A method for preparing a high-strength tungsten alloy wire, characterized in that, It includes the following steps: S1. Add tungsten powder, lanthanum oxide, and grinding balls into a ball mill jar for ball milling to obtain a mixed powder; the mass fraction of lanthanum oxide in the mixed powder is 0.71 - 0.75wt%; S2. Load the mixed powder into a mold for isostatic pressing to obtain a green tungsten blank; S3. Place the green tungsten blank into a microwave oven for sintering to obtain a tungsten blank; place the green tungsten blank into the cylinder of the microwave oven and sinter it in an atmosphere of H2 + N2 with a volume fraction of H2 being 5vol%, where the cylinder rotates at a speed of 5rpm; S4. Heat the tungsten blank and then roll it to obtain tungsten rod 1; S5. Anneal tungsten rod 1 to reduce the internal stress of the tungsten rod, where the annealing temperature is 2100 - 2250°C to obtain tungsten rod 2; S6. Swage tungsten rod 2 to obtain tungsten rod 1, and its logarithmic strain is 0.95 - 1.30; S7. Anneal tungsten rod 1 to obtain tungsten rod 2; the tungsten grain microstructure of tungsten rod 2 is uniform, the average grain diameter of the tungsten grains is 35 - 40μm, and the hardness HV30 of tungsten rod 2 is 385 - 410; S8. Draw tungsten rod 2 to obtain a high-strength tungsten alloy wire, the wire diameter of the high-strength tungsten alloy wire is less than 30μm, the tensile strength ≥6200MPa, and the qualified rate ≥80%.

2. The preparation method of the high-strength tungsten alloy wire according to claim 1, wherein, In the step S1, the grinding balls are agate ball mill beads, the mass ratio of the mixed powder to the grinding balls is (8 - 10):1, the diameter of the grinding balls is 3.5 - 4.0mm, the ball milling speed is 240 - 250rpm, and the ball milling time is 3 - 3.5h.

3. The preparation method of the high-strength tungsten alloy wire according to claim 1, characterized in that, In the step S2, the isostatic pressure is 120 - 130MPa.

4. The preparation method of the high-strength tungsten alloy wire according to claim 1, characterized in that, In the step S3, a tungsten blank with a diameter of 18.5 ± 0.3mm is prepared, the sintering temperature is 1600 - 1850°C, and the sintering time is 20 - 25min.

5. The preparation method of the high-strength tungsten alloy wire according to claim 1, characterized in that, In the step S4, heat the tungsten blank to 1700 - 1800°C for rolling to obtain tungsten rod 1 with a diameter of 9 ± 0.5mm.

6. The preparation method of the high-strength tungsten alloy wire according to claim 1, characterized in that In the step S5, when annealing, tungsten rod 1 moves along its axial direction, and the annealing speed is 0.25 - 0.35m / min to obtain tungsten rod 2.

7. The method for preparing the high-strength tungsten alloy wire according to claim 1, wherein In the step S7, the annealing temperature is 2400 - 2500°C, when annealing, tungsten rod 1 moves along its axial direction, and the annealing speed is 0.35 - 0.50m / min.

8. A high-strength tungsten alloy wire, characterized in that, It is prepared by using the preparation method of the high-strength tungsten alloy wire according to any one of claims 1 - 7.

Images