A tungsten-tantalum-nickel-titanium-vanadium alloy, a preparation method and application thereof

Abstract

The application belongs to the field of tungsten alloy preparation, and particularly relates to a tungsten-tantalum-nickel-titanium-vanadium alloy and a preparation method and application thereof. The alloy comprises tungsten, tantalum, nickel, titanium and vanadium, and the mass ratio of the alloy is 120-200:10-40:10-40:2-18. The preparation method is to mix tungsten powder, tantalum powder, nickel-titanium alloy powder and vanadium powder to obtain mixed powder, and then to form the mixed powder through die pressing and to densify the mixed powder through vacuum sintering. The application uses nickel-titanium alloy powder as a binder phase, thereby realizing the toughening of tungsten particles by tantalum and vanadium elements and improving the mechanical properties of the tungsten alloy. The tungsten-tantalum-nickel-titanium-vanadium alloy developed and prepared by the application can be used as a radiation shielding device, a core of a penetrator, a shell of a shaped charge, a gyro outer rotor body and the like.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of tungsten alloy preparation, and particularly relates to a tungsten-tantalum-nickel-titanium-vanadium alloy and a preparation method and application thereof. BACKGROUND

[0002] Tungsten (W) was first discovered by human beings in the eighteenth century. As a strategic metal, W is widely used in modern industry, national defense and high-tech due to its high density, high strength, high hardness, excellent electrical conductivity and thermal conductivity. The development of science and technology puts forward higher requirements for the strength and toughness of tungsten.

[0003] The addition of tantalum element can effectively improve the performance of tungsten alloy through solid solution strengthening. Tantalum, like tungsten, belongs to the body-centered cubic (BCC) structure, can be infinitely solid-solved with tungsten, and the ordered phase formed in the tungsten-tantalum solid solution can change the symmetry of the tungsten core structure, increase the mobility of dislocations, and improve the performance of tungsten particles. The addition of tantalum can reduce the solubility of tungsten in the binder phase, and play a role in fine grain strengthening. The addition of vanadium element can effectively reduce the elastic modulus of W and improve the ductility of the alloy.

[0004] The current tungsten alloy system (W-Ni-Fe, W-Ni-Cu) will form a large amount of intermetallic compounds between the matrix phase and the solid solution elements after adding solid solution elements. These intermetallic compounds not only consume the solid solution elements and reduce the solid solubility of the solid solution elements in the tungsten particles, but also greatly reduce the performance of the alloy because most of the intermetallic compounds are hard and brittle. Using nickel-titanium as the binder phase of the alloy can effectively solid-solution strengthen the tungsten particles. SUMMARY

[0005] In view of the deficiencies in the prior art, the first object of the present application is to provide a tungsten-tantalum-nickel-titanium-vanadium alloy with solid solution strengthening. The addition of tantalum can introduce ordered phases in the tungsten crystal to produce solid solution strengthening, while reducing the dissolution and precipitation of tungsten in the binder phase to produce fine grain strengthening and improve the strength of the alloy. The addition of vanadium reduces the elastic modulus of W and improves the ductility. The use of nickel-titanium as the binder phase ensures that tantalum and vanadium are solid-solution strengthened into tungsten particles to produce a synergistic strengthening effect.

[0006] The second object of the present application is to provide a preparation method of a tungsten-tantalum-nickel-titanium-vanadium alloy. The method can realize the densification of the alloy at a relatively low temperature, has the advantages of simple process flow, short production cycle, etc., and is suitable for industrial production.

[0007] The third object of the present application is to provide the application of a tungsten-tantalum-nickel-titanium-vanadium alloy. The alloy is used as a raw material in radiation shielding, counterweight and gyro outer rotor body of large-caliber kinetic energy penetrator, which can greatly prolong the service life.

[0008] The tungsten-tantalum-nickel-titanium-vanadium alloy has a mass ratio of tungsten, tantalum, nickel titanium, and vanadium of 120-200:10-40:10-40:2-18.

[0009] The preparation method of the tungsten-tantalum-nickel-titanium-vanadium alloy comprises the following steps: mixing tungsten powder, tantalum powder, vanadium powder, and nickel-titanium alloy powder to obtain mixed powder, pressing the mixed powder to obtain a compact, and sintering the compact in a vacuum environment.

[0010] As a preferred scheme, the mass ratio of the tungsten powder, the tantalum powder, the nickel-titanium alloy powder, and the vanadium powder is 120-200:10-40:10-40:2-18, preferably 140-175:12-30:20-30:3-12, and further preferably 145-170:15-30:22-28:4-11.

[0011] When applied in industry, the mass ratio of the tungsten powder, the tantalum powder, the nickel-titanium alloy powder, and the vanadium powder is further preferably 150-165:16-28.5:24-26:4.5-10.5. This includes the scheme that the mass ratio of the tungsten powder, the tantalum powder, the nickel-titanium alloy powder, and the vanadium powder is 160-164:16-20:18-22:8-12, and also includes the scheme that the mass ratio of the tungsten powder, the tantalum powder, the nickel-titanium alloy powder, and the vanadium powder is 150-154:27-28.5:24-26:4.5-5.5.

[0012] As one of the best limited schemes, the mass ratio of the tungsten powder, the tantalum powder, the nickel-titanium alloy powder, and the vanadium powder is 160-164:16-20:18-22:8-12. This includes the scheme that the mass ratio of the tungsten powder, the tantalum powder, the nickel-titanium alloy powder, and the vanadium powder is 162:18:20:10.

[0013] As one of the best limited schemes, the mass ratio of the tungsten powder, the tantalum powder, the nickel-titanium alloy powder, and the vanadium powder is 150-154:27-28.5:24-26:4.5-5.5. This includes the scheme that the mass ratio of the tungsten powder, the tantalum powder, the nickel-titanium alloy powder, and the vanadium powder is 152:28:25:5.

[0014] In the nickel-titanium alloy powder, the mass ratio of nickel to titanium is (45-55):(45-55).

[0015] The preparation method of the tungsten-tantalum-nickel-titanium-vanadium alloy comprises the following steps: mixing tungsten powder, tantalum powder, vanadium powder, and nickel-titanium alloy powder to obtain mixed powder, pressing the mixed powder to obtain a compact, and sintering the compact in a vacuum environment.

[0016] The key of the preparation method of the present application is that a proper amount of tantalum which can realize infinite solid solution with tungsten is added. The ordered phase formed in the tungsten-tantalum solid solution can improve the symmetric nuclear structure of tungsten, improve the strength of tungsten particles, and at the same time, reduce the solubility of tungsten in the matrix phase, hinder the tungsten particle dissolution and precipitation process, refine the tungsten particles, and play a fine-grain strengthening effect. Adding too much tantalum powder has no positive effect on the overall strength. In the sintering process, the oxygen in the tantalum powder will be adsorbed by titanium to form titanium oxide particles, which will destroy the structure of the binder phase and reduce the mechanical properties of the alloy.

[0017] Vanadium element which can improve the ductility of the alloy is also added to further improve the processability of the alloy. The addition of trace vanadium does not affect the microstructure and uniformity of the alloy.

[0018] It is found that the preliminary weighing work in the vacuum glove box can effectively reduce the oxidation of tungsten and tantalum in the mixing process, reduce the loss of titanium in the sintering process, and reduce the generation of metal compound.

[0019] As a preferred scheme, the tungsten powder is spherical powder with an average particle size of 3-5 μm and a purity of ≧99.8%; the tantalum powder is spherical powder with an average particle size of 3-10 μm and a purity of ≧99.9%; and the rhenium powder is spherical powder with an average particle size of 3-10 μm and a purity of ≧99.9%. The raw materials used in the present application are all spherical powders, because spherical powders have the highest specific surface area under the same mass, can provide the highest sintering activity, and can improve the diffusion capacity between the added elements.

[0020] As a preferred scheme, the mixing is carried out in a three-dimensional mixer for 12-14 h. The three-dimensional mixer can obtain uniformly mixed tungsten-tantalum-nickel-titanium-vanadium powder.

[0021] After mixing, the mass percentage of oxygen in the uniformly mixed tungsten-tantalum-nickel-titanium-vanadium powder is less than or equal to 600 ppm.

[0022] As a preferred scheme, the pressing forming method is die pressing forming. The present application can obtain reliable and dense compacts by using die pressing forming.

[0023] As a preferred scheme, the pressing forming method is die pressing forming, the forming pressure is 450 MPa-650 MPa, preferably 480-520 MPa, and the pressure holding time is 5-10 s. In the technical scheme of the present application, if the pressure value of die pressing is too low, the edges of the powder compact cannot be formed, and if the pressure value is too high, the compact will be layered, so the maximum pressure should not exceed 650 MPa.

[0024] As a preferred scheme, the vacuum degree during sintering is ≦10 -3Pa; since titanium is easy to absorb oxygen, the vacuum degree needs to be strictly controlled during the sintering process of the tungsten-tantalum-nickel-titanium-vanadium alloy to avoid oxidation during the sintering process.

[0025] As a preferred scheme, the sintering process is: heating at a heating rate of 5-20℃ / min to 800-1000℃, preferably 850-900℃, and holding for 10-40min; then heating at a cooling rate of 2-10℃ / min to 1100-1200℃, preferably 1100-1150℃, and holding for 60-300min; then heating at a heating rate of 2-10℃ / min to 1300-1400℃, preferably 1300-1350℃, and holding for 30-90min; finally, cooling at a cooling rate of 5-35℃ / min to room temperature. The technical scheme of the present application first heats the alloy powder to 800-1000℃, so that a preliminary sintering neck is formed between the powders, on the other hand, the temperature in the furnace can be stabilized. Further increasing the sintering temperature to 1300-1400℃ can quickly realize the densification of the blank. At the same time, holding at 1100-1200℃ can further improve the uniformity of the alloy organization and the mechanical properties of the alloy.

[0026] The present application also provides a tungsten-tantalum-nickel-titanium-vanadium alloy obtained by the above preparation method. The tungsten-tantalum-nickel-titanium-vanadium alloy is strengthened by the solid solution of tantalum and vanadium elements, and no intermetallic compound is generated, and the particle size of the alloy matrix is ≤20μm.

[0027] Preferably, the tensile strength of the tungsten-tantalum-nickel-titanium-vanadium alloy is greater than or equal to 800MPa (after optimization, it can be greater than or equal to 970MPa), and the tensile strain is greater than 15%.

[0028] The present application also provides an application of a tungsten-tantalum-nickel-titanium-vanadium alloy, which is used as a raw material for radiation shielding, counterweight and large-caliber kinetic energy penetration device gyro outer rotor body, which not only greatly improves the service life, but also greatly widens the application range of tantalum alloy.

[0029] Compared with the prior art, the present application has the following beneficial effects:

[0030] 1) The alloy system of the present application uses tantalum to strengthen tungsten particles, supplemented by an appropriate amount of vanadium to improve the toughness of the alloy. After the addition of two kinds of solid solution elements, the strength and toughness of the alloy are improved. The strength of the alloy increases with the increase of the content of tantalum element, but the toughness does not change significantly with the further increase of the content of vanadium element. Under the synergistic effect of the two elements, the sintered body shows good strength and toughness. The alloy designed in the present application can prepare a tungsten-tantalum-molybdenum alloy with a strength of more than 970MPa.

[0031] 2) The present application adds solid solution element tantalum by using a three-dimensional mixer and is formed by die molding; the designed alloy system successfully realizes solid solution strengthening of tungsten in a traditional sintering mode.

[0032] 3) The tungsten-tantalum-nickel-titanium-vanadium alloy provided by the present application can be used for radiation shielding, counterweight, large-caliber kinetic energy penetrator, gyro outer rotor body and the like, greatly widening the application of tantalum alloy. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The original morphology of the tungsten element powder, the tantalum element powder, the vanadium element powder and the nickel-titanium alloy powder used in Example 1.

[0034] Figure 2 The morphology of the tungsten-tantalum-nickel-titanium-vanadium alloy obtained in Example 1;

[0035] Figure 3 The morphology of the tungsten-tantalum-nickel-titanium-vanadium alloy obtained in Example 2;

[0036] Figure 4 The morphology of the tungsten-tantalum-nickel-titanium-vanadium alloy obtained in Example 3;

[0037] Figure 5 The morphology of the tungsten-tantalum-nickel-titanium-vanadium alloy obtained in Example 4;

[0038] Figure 6 The morphology of the tungsten-tantalum-nickel-titanium-vanadium alloy obtained in Example 5;

[0039] Figure 7 The macroscopic morphology after die molding of Comparative Example 2 and Comparative Example 3, wherein (a) is the macroscopic morphology after die molding of Comparative Example 2, and (b) is the macroscopic morphology after die molding of Comparative Example 3.

[0040] Figure 8 The tensile strength and average relative density statistical diagram of the tungsten-tantalum-nickel-titanium-vanadium alloy obtained in Example 1, Example 2, Example 3, Example 4, Example 5, Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 4.

[0041] Figure 1 consisting of Figure 1 (a), Figure 1 (b), Figure 1 (c), Figure 1 (d). Wherein Figure 1 (a) is a tungsten powder morphology, Figure 1 (b) is a tantalum powder morphology, Figure 1 (c) is a vanadium powder morphology, Figure 1 (d) is a mixed powder morphology. From Figure 1It can be seen that the W powder presents an equiaxed polyhedral shape, the Ta powder and the V powder mostly present irregular polygonal shapes, and the NiTi alloy powder presents a regular spherical shape.

[0042] Figure 2 Comparison of the morphology of the tungsten-tantalum-nickel-titanium-vanadium alloy prepared in Example 1 Figure 3 It can be seen that the reduction of the sintering time and the sintering temperature makes the binder phase unevenly distributed, large molten pools appear, the uniformity of the material is reduced, and the performance of the alloy is reduced.

[0043] From Figure 2 , Figure 3 , Figure 4 , Figure 5 Obvious liquid phase sintering characteristics can be observed.

[0044] From Figure 6 It can be seen that in Example 6, the dissolution and precipitation of tungsten particles are not sufficient due to the too low sintering temperature.

[0045] Figure 7 (a) is the forming condition of the green body when the pressure is too low in the powder forming process. It can be observed that the edge of the green body is irregular, a large amount of powder is separated from the green body, and the overall density of the sintered body is low. Figure 7 (b) is the forming condition of the green body when the pressure is too high in the powder forming process. The green body is layered.

[0046] Figure 8 It can be found in Table 1 that the performance of the alloy is significantly improved due to the addition of vanadium. However, the addition of excessive V element makes the proportion of NiTi as the liquid phase component insufficient, the ability to dissolve W particles is poor, and the lack of binder phase leads to too high tungsten-tungsten connectivity, which greatly reduces the mechanical performance of the alloy. DETAILED DESCRIPTION

[0047] In order to have a clearer understanding of the technical features, objectives and beneficial effects of the present application, the technical solutions of the present application will be described in detail below, but it cannot be understood as limiting the scope of the present application.

[0048] Example 1

[0049] A preparation method of a tungsten-tantalum-nickel-titanium-vanadium alloy, comprising the following steps:

[0050] Step 1: Obtain mixed powder using a three-dimensional mixer

[0051] In a vacuum glove box, take tungsten powder 162 g, average particle size 3-5 microns, purity greater than 99.8%; tantalum powder 18 g, average particle size 3-10 microns, purity greater than 99.9%; take vanadium powder 5 g, average particle size 3-10 microns, purity greater than 99.9%; take nickel-titanium alloy powder 25 g (in the nickel-titanium alloy powder, the mass ratio of nickel to titanium is 55:45), average particle size 5-23 microns, purity greater than 99.9%, put the above powders together into a tungsten carbide mixing tank. Take the mixing tank out of the vacuum glove box and put it into a three-dimensional mixer for 12 hours of mixing (after mixing, the mass percentage of oxygen is less than or equal to 500 ppm).

[0052] Step 2: Obtain a green body using mold pressing

[0053] Put 180 g of mixed powder into a mold and press at a pressure of 500 MPa for 5 s.

[0054] Step 3: Sintering of tungsten-tantalum-nickel-titanium-vanadium alloy

[0055] The sintering process uses an AL-2000-MG high vacuum heat treatment furnace of Sichuan Lide Technology Co., Ltd. During the sintering process, the vacuum degree in the furnace is maintained at 10 -3 Pa below; heat at a rate of 10 ℃ / min to 900 ℃, keep for 30 min, then heat at a rate of 5 ℃ / min to 1200 ℃, keep for 180 min, then heat at a rate of 5 ℃ / min to 1320 ℃, keep for 120 min, then cool at a rate of 20 ℃ / min to room temperature to obtain a tungsten-tantalum-nickel-titanium-vanadium alloy.

[0056] The average relative density of the tungsten-tantalum-nickel-titanium-vanadium alloy prepared in this example is 98.0%, the tensile strength is 924 MPa, and the total elongation is 9.5%.

[0057] Example 2

[0058] Step 1: Obtain mixed powder using a three-dimensional mixer

[0059] In a vacuum glove box, take tungsten powder 162 g, average particle size 3-5 microns, purity greater than 99.8%; tantalum powder 18 g, average particle size 3-10 microns, purity greater than 99.9%; take vanadium powder 5 g, average particle size 3-10 microns, purity greater than 99.9%; take nickel-titanium alloy powder 25 g (in the nickel-titanium alloy powder, the mass ratio of nickel to titanium is 55:45), average particle size 5-23 microns, purity greater than 99.9%, put the above powders together into a tungsten carbide mixing tank. Take the mixing tank out of the vacuum glove box and put it into a three-dimensional mixer for 12 hours of mixing (after mixing, the mass percentage of oxygen is less than or equal to 500 ppm).

[0060] Step 2: Obtain a green body by using die compaction

[0061] 180 g of the mixed powder was put into a mold and pressed at a pressure of 500 MPa for 5 s.

[0062] Step 3: Sintering of the tungsten-tantalum-nickel-titanium-vanadium alloy

[0063] The sintering process used an AL-2000-MG high vacuum heat treatment furnace of Sichuan Lide Technology Co., Ltd. During the sintering process, the vacuum degree in the furnace was maintained at 10 -3 Pa below; the temperature was raised to 800℃ at a rate of 10℃ / min, maintained for 30 min, then raised to 1200℃ at a rate of 5℃ / min, maintained for 60 min, then raised to 1300℃ at a rate of 5℃ / min, maintained for 120 min, and then cooled to room temperature with the furnace, to obtain the tungsten-tantalum-nickel-titanium-vanadium alloy.

[0064] The average relative density of the tungsten-tantalum-nickel-titanium-vanadium alloy prepared in this example was 93.2%, the tensile strength was 902 MPa, and the total elongation was 9.0%.

[0065] Example 3

[0066] Step 1: Obtain a mixed powder by using a three-dimensional mixer

[0067] In a vacuum glove box, 162 g of tungsten powder with an average particle size of 3-5 microns and a purity of greater than 99.8%, 18 g of tantalum powder with an average particle size of 3-10 microns and a purity of greater than 99.9%, 10 g of vanadium powder with an average particle size of 3-10 microns and a purity of greater than 99.9%, and 20 g of nickel-titanium alloy powder (the mass ratio of nickel to titanium in the nickel-titanium alloy powder was 55:45) with an average particle size of 5-23 microns and a purity of greater than 99.9% were taken and put together into a tungsten carbide mixing tank. The mixing tank was taken out of the vacuum glove box and put into a three-dimensional mixer for mixing for 12 hours (after mixing, the mass percentage of oxygen was less than or equal to 500 ppm).

[0068] Step 2: Obtain a green body by using die compaction

[0069] 180 g of the mixed powder was put into a mold and pressed at a pressure of 500 MPa for 5 s.

[0070] Step 3: Sintering of the tungsten-tantalum-nickel-titanium-vanadium alloy

[0071] The sintering process used an AL-2000-MG high vacuum heat treatment furnace of Sichuan Lide Technology Co., Ltd. During the sintering process, the vacuum degree in the furnace was maintained at 10 -3Pa below; temperature is raised to 900°C at a rate of 10°C / min, and kept for 30 min, then raised to 1200°C at a rate of 5°C / min, and kept for 180 min, then raised to 1320°C at a rate of 5°C / min, and kept for 120 min, and then cooled to room temperature at a rate of 20°C / min, to obtain the tungsten-tantalum-nickel-titanium-vanadium alloy.

[0072] The average relative density of the tungsten-tantalum-nickel-titanium-vanadium alloy prepared in this example is 98.6%, the tensile strength is 966 MPa, and the total elongation is 10.1%.

[0073] Example 4

[0074] A method for preparing a tungsten-tantalum-nickel-titanium-vanadium alloy, comprising the following steps:

[0075] Step 1: obtaining mixed powder using a three-dimensional mixer

[0076] In a vacuum glove box, take 152 g of tungsten powder with an average particle size of 3-5 microns and a purity of more than 99.8%, 28 g of tantalum powder with an average particle size of 3-10 microns and a purity of more than 99.9%, 5 g of vanadium powder with an average particle size of 3-10 microns and a purity of more than 99.9%, and 25 g of nickel-titanium alloy powder with an average particle size of 5-23 microns and a purity of more than 99.9%, and put them together into a tungsten carbide mixing tank. Take the mixing tank out of the vacuum glove box and put it into a three-dimensional mixer for 12 hours of mixing (after mixing, the mass percentage of oxygen is less than or equal to 500 ppm).

[0077] Step 2: obtaining a green body using die compaction

[0078] Put 180 g of mixed powder into a mold and press at a pressure of 500 MPa for 5 s.

[0079] Step 3: sintering of the tungsten-tantalum-nickel-titanium-vanadium alloy

[0080] The sintering process uses an AL-2000-MG high-vacuum heat treatment furnace of Sichuan Lide Technology Co., Ltd. During the sintering process, the vacuum degree in the furnace is maintained at 10 -3 Pa below; temperature is raised to 900°C at a rate of 10°C / min, and kept for 30 min, then raised to 1200°C at a rate of 5°C / min, and kept for 180 min, then raised to 1320°C at a rate of 5°C / min, and kept for 120 min, and then cooled to room temperature at a rate of 20°C / min, to obtain the tungsten-tantalum-nickel-titanium-vanadium alloy.

[0081] The average relative density of the tungsten-tantalum-nickel-titanium-vanadium alloy prepared in this example is 98.1%, the tensile strength is 982 MPa, and the total elongation is 10.9%.

[0082] Example 5

[0083] A method for preparing a tungsten-tantalum-nickel-titanium-vanadium alloy, comprising the following steps:

[0084] Step 1: obtaining mixed powder using a three-dimensional mixer

[0085] In a vacuum glove box, take 162 g of tungsten powder with an average particle size of 3-5 microns and a purity of greater than 99.8%, 18 g of tantalum powder with an average particle size of 3-10 microns and a purity of greater than 99.9%, 5 g of vanadium powder with an average particle size of 3-10 microns and a purity of greater than 99.9%, and 25 g of nickel-titanium alloy powder (the mass ratio of nickel to titanium in the nickel-titanium alloy powder is 55:45) with an average particle size of 5-23 microns and a purity of greater than 99.9%. Put the above powders together into a tungsten carbide mixing tank. Take the mixing tank out of the vacuum glove box and put it into a three-dimensional mixer for 12 hours of mixing (after mixing, the mass percentage of oxygen is less than or equal to 500 ppm).

[0086] Step 2: obtaining a green body using die molding

[0087] Put 180 g of mixed powder into a mold and press at a pressure of 500 MPa for 5 s.

[0088] Step 3: sintering of the tungsten-tantalum-nickel-titanium-vanadium alloy

[0089] The sintering process uses an AL-2000-MG high vacuum heat treatment furnace of Sichuan Lide Technology Co., Ltd. During the sintering process, the vacuum degree in the furnace is maintained at 10 -3 Pa or below; heat at a rate of 10 ℃ / min to 900 ℃, maintain for 30 min, then heat at a rate of 5 ℃ / min to 1000 ℃, maintain for 180 min, then heat at a rate of 5 ℃ / min to 1200 ℃, maintain for 120 min, then cool at a rate of 20 ℃ / min to room temperature, to obtain a tungsten-tantalum-nickel-titanium-vanadium alloy.

[0090] The average relative density of the tungsten-tantalum-nickel-titanium-vanadium alloy prepared in this example is 98.0%, the tensile strength is 346 MPa, and the total elongation is 2.5%.

[0091] Comparative Example 1

[0092] The comparative example is identical to example 1 except for step 1 : in the vacuum glove box, take 162 g of tungsten powder having an average particle size of 3-5 microns and a purity of greater than 99.8%; take 18 g of tantalum powder having an average particle size of 3-10 microns and a purity of greater than 99.9%; take 30 g of nickel-titanium alloy powder having an average particle size of 5-23 microns and a purity of greater than 99.9%, and place the powders together in a tungsten carbide mixing jar. Take the mixing jar out of the vacuum glove box and place it in a three-dimensional mixer, and mix for 12 hours (after mixing, the mass percentage of oxygen is less than or equal to 500 ppm).

[0093] The material produced in the comparative example has an average relative density of 97.6%, a tensile strength of 810 MPa, and a total elongation of 9.2%.

[0094] Comparative Example 2

[0095] The comparative example is identical to example 1 except for step 2: place 180 g of the mixed powder into a mold, and press at a pressure of 300 MPa for 5 s

[0096] The material produced in the comparative example has an average relative density of 88.6%, a tensile strength of 870 MPa, and a total elongation of 9.5%.

[0097] Comparative Example 3

[0098] The comparative example is identical to example 1 except for step 2: place 180 g of the mixed powder into a mold, and press at a pressure of 600 MPa for 5 s

[0099] The material produced in the comparative example has an average relative density of 98%, a tensile strength of 912 MPa, and a total elongation of 10.1%.

[0100] Comparative Example 4

[0101] The comparative example is identical to example 1 except for step 1 : in the vacuum glove box, take 162 g of tungsten powder having an average particle size of 3-5 microns and a purity of greater than 99.8%; take 18 g of tantalum powder having an average particle size of 3-10 microns and a purity of greater than 99.9%; take 20 g of vanadium powder having an average particle size of 3-10 microns and a purity of greater than 99.9%; take 10 g of nickel-titanium alloy powder (in the nickel-titanium alloy powder, the mass ratio of nickel to titanium is 55:45) having an average particle size of 5-23 microns and a purity of greater than 99.9%, and place the powders together in a tungsten carbide mixing jar. Take the mixing jar out of the vacuum glove box and place it in a three-dimensional mixer, and mix for 12 hours (after mixing, the mass percentage of oxygen is less than or equal to 500 ppm).

[0102] The material produced in this comparative example had an average relative density of 97.6%, a tensile strength of 410 MPa and a total elongation of 2.2%.

Claims

1. A method for preparing a tungsten-tantalum-nickel-titanium-vanadium alloy, characterized in that: In the alloy, the mass ratio of tungsten, tantalum, nickel-titanium, and vanadium is 120~200:10~40:10~40:2~18; the mass ratio of nickel to titanium is (45~55):(45~55); the preparation method is as follows: tungsten powder, tantalum powder, vanadium powder, and nickel-titanium alloy powder are mixed to obtain a mixed powder, the mixed powder is pressed into a compact, and sintered in a vacuum environment to obtain the alloy; the mass ratio of tungsten powder, tantalum powder, nickel-titanium alloy powder, and vanadium powder is 120~200:10~40:10~40:2~18; in the nickel-titanium alloy powder, the mass ratio of nickel to titanium is (45~55):(45~55); The pressing and molding method is compression molding, with a molding pressure of 480~520MPa and a holding time of 5~10s; The vacuum degree during sintering is ≤10. -3 Pa; The sintering process is as follows: the temperature is increased to 800-1000℃ at a heating rate of 5-20℃ / min and held for 10-40min; then the temperature is increased to 1100-1200℃ at a heating rate of 2-10℃ / min and held for 60-300min; then the temperature is increased to 1300-1400℃ at a heating rate of 2-10℃ / min and held for 30-90min; finally, the temperature is decreased to room temperature at a cooling rate of 5-35℃ / min.

2. The method for preparing the tungsten-tantalum-nickel-titanium-vanadium alloy according to claim 1, characterized in that: The mass ratio of tungsten powder, tantalum powder, nickel-titanium alloy powder and vanadium powder is 140~175:12~30:20~30:3~12.

3. The method for preparing the tungsten-tantalum-nickel-titanium-vanadium alloy according to claim 2, characterized in that: The mass ratio of the tungsten powder, tantalum powder, nickel-titanium alloy powder and vanadium powder is 145~170:15~30:22~28:4~11.

4. The method for preparing the tungsten-tantalum-nickel-titanium-vanadium alloy according to claim 1, characterized in that: The mass ratio of tungsten powder, tantalum powder, nickel-titanium alloy powder and vanadium powder is 160~164:16~20:18~22:8~12; or the mass ratio of tungsten powder, tantalum powder, nickel-titanium alloy powder and vanadium powder is 150~154:27~28.5:24~26:4.5~5.

5.

5. The method for preparing a tungsten-tantalum-nickel-titanium-vanadium alloy according to claim 1, characterized in that: The tungsten powder has an average particle size of 3~5µm and a purity of ≥99.8%. The tantalum powder has an average particle size of 3~10µm and a purity of ≥99.9%. The nickel-titanium alloy powder has an average particle size of 5~20µm and a purity of ≥99.9%. The vanadium powder has an average particle size of 3~5µm and a purity of ≥99.9%.

6. The method for preparing a tungsten-tantalum-nickel-titanium-vanadium alloy according to claim 1, characterized in that: Each raw material is prepared in a vacuum or protective atmosphere and then mixed in a three-dimensional mixer for 10-16 hours to obtain a uniformly mixed powder.

7. An application of the tungsten-tantalum-nickel-titanium-vanadium alloy prepared by the method described in claim 1, characterized in that: The applications include at least one of the following: radiation shield, armor-piercing projectile core, shaped charge projectile casing, and gyroscope outer rotor.

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