An ultra-high temperature high-strength tantalum alloy and a preparation method thereof

Abstract

The application provides a preparation method of ultrahigh-temperature high-strength tantalum alloy. Ta particles, W particles and Hf particles are used as raw materials to prepare an ultrahigh-temperature high-strength tantalum alloy with a component ratio of Ta: 75-79 wt.%, W: 15-20 wt.% and Hf: 1-5 wt.% in a vacuum arc furnace, and the material is homogenized by adopting a vacuum high-temperature long-time annealing mode. The prepared Ta-W-Hf ultrahigh-temperature alloy is single-phase BCC structure, the yield strength of the Ta-W-Hf alloy in room temperature compression test is 822-1032 MPa, and more than 40% compression strain is maintained; the yield strength of Ta-20W-5Hf in 2000 DEG C high-temperature compression test is 340 MPa, and the alloy has excellent high-temperature strength, and the system alloy is expected to be used as a new generation of ultrahigh-temperature bearing material and has great application potential in important high-temperature parts of the aerospace industry.

Description

Technical Field

[0001] This invention belongs to the field of structural materials, specifically relating to an ultra-high temperature high-strength tantalum alloy and its preparation method. Background Technology

[0002] In the aerospace field, with the continuous increase in aircraft speed, more stringent requirements are being placed on the high-temperature resistance and mechanical properties of materials under high-temperature environments. Traditional nickel-based single-crystal superalloys have melting points of 1400–1500℃, which cannot meet the service requirements at higher temperatures. While emerging refractory high-entropy alloys NbMoTaW and NbMoTaWV still have high strength at 1600℃, they suffer from severe room-temperature brittleness and poor oxidation resistance, making them difficult to apply in practice. Tantalum-tungsten alloys have melting points exceeding 2000℃. Commercially available materials such as Ta-2.5W, Ta-7.5W, and Ta-10W all exhibit tensile strains exceeding 20% ​​at room temperature and possess excellent cold-working properties. Recent studies have shown that Ta-20W has compressive strains exceeding 20% ​​at room temperature and a high-temperature strength of 236 MPa at 2000℃. Tantalum-tungsten alloys have enormous potential for application in the aerospace field as ultra-high-temperature materials.

[0003] To meet higher high-temperature strength requirements, solid solution strengthening is considered to enhance the room-temperature and high-temperature strength of Ta-W alloys. The refractory metal element Hf can dissolve in the Ta-W matrix and also has a high affinity for oxygen, effectively binding and absorbing oxygen near grain boundaries, which is beneficial for improving the high-temperature strength of the material. Currently, there are no reports on Ta-W-Hf alloys; alloying control of tantalum alloys holds promise for further improving their room-temperature and high-temperature strength. Summary of the Invention

[0004] The purpose of this invention is to provide a simple method for preparing an ultra-high temperature high-strength tantalum alloy, and the prepared tantalum alloy has excellent high-temperature strength.

[0005] To achieve the above objectives, the preparation method of the present invention includes the following steps:

[0006] Step 1: Mix 75-80% Ta particles, 15-20% W powder and 1-5% Hf particles evenly by mass percentage to obtain tantalum alloy raw material;

[0007] Step 2: Place the tantalum alloy raw material in the water-cooled crucible of the non-consumable electrode arc furnace. After closing the furnace door, close the venting valve (i.e., the vacuum breaking valve), turn on the mechanical pump to evacuate to 20 Pa, and then open the molecular pump and its two control valves to achieve a vacuum level of 2 × 10⁻⁶ Pa inside the furnace. -3 Pa~6×10 -3After Pa, close the vacuum gauge, molecular pump and its near-furnace valve (high valve), and at the same time open the argon valve to fill the furnace with argon. When the furnace pressure reaches 0.04-0.05 MPa, close the argon valve. After the molecular pump speed drops to 0, close the far-furnace valve (diffusion valve) of the molecular pump and the mechanical pump.

[0008] Step 3: Place the tungsten needle 3-5mm directly above the titanium ball to start arc melting of the titanium ball. The melting current is 300-350A. Then place the tungsten needle 3-5mm directly above the tantalum alloy raw material, turn on the electromagnetic stirring system, start arc melting, and the melting current is 500-600A. After melting 10 times, turn off the power and cool for 10-15 minutes. Open the vacuum valve and open the furnace door to obtain a smooth surface and uniformly shaped disc structure sample.

[0009] Step 4: Place the arc-melted sample in a high-vacuum, high-temperature furnace, and use a mechanical pump and a diffusion pump to bring the furnace pressure to 1×10⁻⁶. -3 Pa ~ 5 × 10 -3 After Pa, the sample was annealed by heating from room temperature to 1600℃ at a heating rate of 10℃ / min and holding for 15 hours. Then, it was cooled to room temperature in the furnace to obtain the Ta-W-Hf alloy.

[0010] In step 1, the purity of Ta particles, W powder, and Hf particles is greater than 99.95%.

[0011] Before melting in the non-consumable electrode arc furnace in step 2, turn on the cooling water, open the vent valve and open the furnace door, wipe the copper crucible station with 20% hydrochloric acid and ethanol, and put in the tantalum alloy raw material prepared in step 1 after cleaning.

[0012] In step 3, to ensure sample uniformity, the sample is flipped between each two melting processes, with at least a 5-minute interval between each melting process.

[0013] The ultra-high temperature high-strength tantalum alloy prepared by the above method, the Ta-W-Hf system alloy, has a typical single-phase BCC structure.

[0014] The prepared ultra-high temperature high-strength tantalum alloy, Ta-W-Hf series alloy, has a yield strength of 822-1032 MPa in room temperature compression test, and the material still retains more than 40% of the compressive strain.

[0015] The prepared ultra-high temperature high-strength tantalum alloy, Ta-20W-5Hf alloy, has a yield strength of 340MPa in an ultra-high temperature compression test at 2000℃.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] This invention selects Hf element to replace Ta in solid-solution Ta-W alloys, and regulates the alloy properties by adjusting the Hf content. The results show that the prepared Ta-W-Hf alloys are all single-phase BCC structures. In room temperature compression tests, the yield strengths of Ta-20W-3Hf and Ta-20W-5Hf ultra-high temperature alloys are 961 MPa and 1032 MPa, respectively, which are significantly improved compared with the previously reported Ta-20W, and can still maintain more than 40% of the compressive strain. In ultra-high temperature compression tests at 2000℃, the yield strength of Ta-20W-5Hf is about 340 MPa, which is better than the 236 MPa of Ta-20W. Attached Figure Description

[0018] Figure 1 This is the XRD pattern of the Ta-W-Hf superheated alloy obtained in Example 1 of this invention.

[0019] Figure 2 The stress-strain curves of the Ta-W-Hf system obtained in Example 1 of this invention are obtained from room temperature compression tests.

[0020] Figure 3 The stress-strain curve of the Ta-20W-5Hf sample prepared in Example 1 of this invention is obtained by compression testing at 2000℃.

[0021] Figure 4 The surface morphology of the Ta-20W-5Hf sample obtained in Example 1 of this invention is shown. Detailed Implementation

[0022] Example 1:

[0023] Step 1: Mix 75% Ta particles, 20% W powder and 5% Hf particles evenly by mass percentage to obtain tantalum alloy raw material. The purity of Ta particles, W powder and Hf particles is greater than 99.95%.

[0024] Step 2: Melt using a non-consumable electrode arc furnace. Turn on the cooling water, open the vent valve and furnace door. Wipe the copper crucible area with 20% hydrochloric acid and ethanol. After cleaning, place the tantalum alloy raw material in the water-cooled crucible of the non-consumable electrode arc furnace. After closing the furnace door, close the vent valve (also known as the vacuum valve). Turn on the mechanical pump to evacuate to 20 Pa to create a suitable environment for the molecular pump. Then, open the molecular pump and its two control valves to achieve a vacuum of 4 × 10⁻⁶ Pa inside the furnace. -3 After Pa, close the vacuum gauge, molecular pump and its near-furnace valve (high valve), and at the same time open the argon valve to fill the furnace with argon. When the furnace pressure reaches 0.04 MPa, close the argon valve. After the molecular pump speed drops to 0, close the far-furnace valve (diffusion valve) of the molecular pump and the mechanical pump.

[0025] Step 3: Place the tungsten needle 3mm directly above the titanium ball to start arc melting of the titanium ball. The melting current is 300A. This further absorbs the residual oxygen in the furnace cavity and also serves to check the sealing of the furnace body. Next, place the tungsten needle 3mm directly above the tantalum alloy raw material, turn on the electromagnetic stirring system, and start arc melting. The melting current is 500A. After melting 10 times, the sample should be turned over between every two meltings to ensure the uniformity of the sample. There should be at least a 5-minute interval between every two meltings to ensure that the temperature of the water-cooled crucible does not become too high and soften or break, causing danger. At the end of the last melting, quickly reduce the current and turn it off to ensure that the sample does not have any dents. Turn off the power and cool for 15 minutes. Open the vacuum valve and open the furnace door to obtain a smooth, uniformly shaped disc structure sample.

[0026] Step 4: Place the arc-melted sample in a high-vacuum, high-temperature furnace, and use a mechanical pump and a diffusion pump to bring the furnace pressure to 5 × 10⁻⁶. -3 After Pa, the sample was annealed by heating from room temperature to 1600℃ at a heating rate of 10℃ / min and holding for 15 hours. Then, it was cooled to room temperature in the furnace to obtain the Ta-W-Hf alloy.

[0027] from Figure 1 It can be seen that after Hf is dissolved in the solid, the Ta-W-Hf superheated alloy still maintains the single-phase body-centered cubic (BCC) structure.

[0028] from Figure 2 As can be seen from the data, the yield strength of the Ta-W-Hf series samples is 822-1032 MPa. The above results show that Hf can significantly improve the strength of the material at room temperature and the compressive strain exceeds 40%.

[0029] from Figure 3 As can be seen, Ta-20W-5Hf has a yield strength of 340MPa and exhibits excellent high-temperature strength.

[0030] from Figure 4 It can be seen that Ta-20W-5Hf forms equiaxed grains with uniform size distribution.

[0031] Example 2:

[0032] Step 1: Mix 77% Ta particles, 20% W powder and 3% Hf particles evenly by mass percentage to obtain tantalum alloy raw material. The purity of Ta particles, W powder and Hf particles is greater than 99.95%.

[0033] Step 2: Melt using a non-consumable electrode arc furnace. Turn on the cooling water, open the vent valve and furnace door. Wipe the copper crucible area with 20% hydrochloric acid and ethanol. After cleaning, place the tantalum alloy raw material in the water-cooled crucible of the non-consumable electrode arc furnace. After closing the furnace door, close the vent valve (also known as the vacuum valve). Turn on the mechanical pump to evacuate to 20 Pa to create a suitable environment for the molecular pump. Then, open the molecular pump and its two control valves to achieve a vacuum of 4 × 10⁻⁶ Pa inside the furnace. -3 After Pa, close the vacuum gauge, molecular pump and its near-furnace valve (high valve), and at the same time open the argon valve to fill the furnace with argon. When the furnace pressure reaches 0.05 MPa, close the argon valve. After the molecular pump speed drops to 0, close the far-furnace valve (diffusion valve) of the molecular pump and the mechanical pump.

[0034] Step 3: Place the tungsten needle 4mm directly above the titanium ball to start arc melting of the titanium ball. The melting current is 320A to further absorb the residual oxygen in the furnace cavity and also to check the sealing of the furnace body. Then place the tungsten needle 4mm directly above the tantalum alloy raw material, turn on the electromagnetic stirring system, and start arc melting. The melting current is 550A. After melting 10 times, the sample should be turned over between every two meltings to ensure the uniformity of the sample. There should be at least a 5-minute interval between every two meltings to ensure that the temperature of the water-cooled crucible does not become too high and soften and break, causing danger. At the end of the last melting, quickly reduce the current and turn it off to ensure that the sample does not have any dents. Turn off the power and cool for 15 minutes. Open the vacuum valve and open the furnace door to obtain a smooth and uniformly shaped disc structure sample.

[0035] Step 4: Place the arc-melted sample in a high-vacuum, high-temperature furnace, and use a mechanical pump and a diffusion pump to bring the furnace pressure to 5 × 10⁻⁶. -3 After Pa, the sample was annealed by heating from room temperature to 1600℃ at a heating rate of 10℃ / min and holding for 15 hours. Then, it was cooled to room temperature in the furnace to obtain the Ta-W-Hf alloy.

[0036] Example 3:

[0037] Step 1: Mix 79% Ta particles, 20% W powder and 1% Hf particles evenly by mass percentage to obtain tantalum alloy raw material. The purity of Ta particles, W powder and Hf particles is greater than 99.95%.

[0038] Step 2: Melt using a non-consumable electrode arc furnace. Turn on the cooling water, open the vent valve and furnace door. Wipe the copper crucible area with 20% hydrochloric acid and ethanol. After cleaning, place the tantalum alloy raw material in the water-cooled crucible of the non-consumable electrode arc furnace. After closing the furnace door, close the vent valve (also known as the vacuum valve). Turn on the mechanical pump to evacuate to 20 Pa to create a suitable environment for the molecular pump. Then, open the molecular pump and its two control valves to achieve a vacuum of 4 × 10⁻⁶ Pa inside the furnace. -3After Pa, close the vacuum gauge, molecular pump and its near-furnace valve (high valve), and at the same time open the argon valve to fill the furnace with argon. When the furnace pressure reaches 0.04 MPa, close the argon valve. After the molecular pump speed drops to 0, close the far-furnace valve (diffusion valve) of the molecular pump and the mechanical pump.

[0039] Step 3: Place the tungsten needle 5mm directly above the titanium ball to start arc melting of the titanium ball. The melting current is 350A. This further absorbs the residual oxygen in the furnace cavity and also serves to check the sealing of the furnace body. Next, place the tungsten needle 5mm directly above the tantalum alloy raw material, turn on the electromagnetic stirring system, and start arc melting. The melting current is 530A. After melting 10 times, the sample should be turned over between every two meltings to ensure the uniformity of the sample. There should be at least a 5-minute interval between every two meltings to ensure that the temperature of the water-cooled crucible does not become too high and soften or break, causing danger. At the end of the last melting, quickly reduce the current and turn it off to ensure that the sample does not have any dents. Turn off the power and cool for 15 minutes. Open the vacuum valve and open the furnace door to obtain a smooth, uniformly shaped disc structure sample.

[0040] Step 4: Place the arc-melted sample in a high-vacuum, high-temperature furnace, and use a mechanical pump and a diffusion pump to bring the furnace pressure to 5 × 10⁻⁶. -3 After Pa, the sample was annealed by heating from room temperature to 1600℃ at a heating rate of 10℃ / min and holding for 15 hours. Then, it was cooled to room temperature in the furnace to obtain the Ta-W-Hf alloy.

[0041] Example 4

[0042] Step 1: Mix 80% Ta particles, 15% W powder and 5% Hf particles evenly by mass percentage to obtain tantalum alloy raw material. The purity of Ta particles, W powder and Hf particles is greater than 99.95%.

[0043] Step 2: Melt using a non-consumable electrode arc furnace. Turn on the cooling water, open the vent valve and furnace door. Wipe the copper crucible area with 20% hydrochloric acid and ethanol. After cleaning, place the tantalum alloy raw material in the water-cooled crucible of the non-consumable electrode arc furnace. After closing the furnace door, close the vent valve (also known as the vacuum valve). Turn on the mechanical pump to evacuate to 20 Pa to create a suitable environment for the molecular pump. Then, open the molecular pump and its two control valves to achieve a vacuum of 2 × 10⁻⁶ Pa inside the furnace. -3 After Pa, close the vacuum gauge, molecular pump and its near-furnace valve (high valve), and at the same time open the argon valve to fill the furnace with argon. When the furnace pressure reaches 0.05 MPa, close the argon valve. After the molecular pump speed drops to 0, close the far-furnace valve (diffusion valve) of the molecular pump and the mechanical pump.

[0044] Step 3: Place the tungsten needle 4mm directly above the titanium ball to start arc melting of the titanium ball. The melting current is 310A. This further absorbs the residual oxygen in the furnace cavity and also serves to check the sealing of the furnace body. Next, place the tungsten needle 4mm directly above the tantalum alloy raw material, turn on the electromagnetic stirring system, and start arc melting. The melting current is 600A. After melting 10 times, the sample should be turned over between every two meltings to ensure the uniformity of the sample. There should be at least a 5-minute interval between every two meltings to ensure that the temperature of the water-cooled crucible does not become too high and soften or break, causing danger. At the end of the last melting, quickly reduce the current and turn it off to ensure that the sample does not have any dents. Turn off the power and cool for 13 minutes. Open the vacuum valve and open the furnace door to obtain a smooth, uniformly shaped disc structure sample.

[0045] Step 4: Place the arc-melted sample in a high-vacuum, high-temperature furnace, and use a mechanical pump and a diffusion pump to bring the furnace pressure to 3 × 10⁻⁶. -3 After Pa, the sample was annealed by heating from room temperature to 1600℃ at a heating rate of 10℃ / min and holding for 15 hours. Then, it was cooled to room temperature in the furnace to obtain the Ta-W-Hf alloy.

[0046] Example 5

[0047] Step 1: Mix 76% Ta particles, 19% W powder and 5% Hf particles evenly by mass percentage to obtain tantalum alloy raw material. The purity of Ta particles, W powder and Hf particles is greater than 99.95%.

[0048] Step 2: Melt using a non-consumable electrode arc furnace. Turn on the cooling water, open the vent valve and furnace door. Wipe the copper crucible area with 20% hydrochloric acid and ethanol. After cleaning, place the tantalum alloy raw material in the water-cooled crucible of the non-consumable electrode arc furnace. After closing the furnace door, close the vent valve (also known as the vacuum valve). Turn on the mechanical pump to evacuate to 20 Pa to create a suitable environment for the molecular pump. Then, open the molecular pump and its two control valves to achieve a vacuum of 5 × 10⁻⁶ Pa inside the furnace. -3 After Pa, close the vacuum gauge, molecular pump and its near-furnace valve (high valve), and at the same time open the argon valve to fill the furnace with argon. When the furnace pressure reaches 0.04 MPa, close the argon valve. After the molecular pump speed drops to 0, close the far-furnace valve (diffusion valve) of the molecular pump and the mechanical pump.

[0049] Step 3: Place the tungsten needle 5mm directly above the titanium ball to start arc melting of the titanium ball. The melting current is 330A. This further absorbs the residual oxygen in the furnace cavity and also serves to check the sealing of the furnace body. Next, place the tungsten needle 5mm directly above the tantalum alloy raw material, turn on the electromagnetic stirring system, and start arc melting. The melting current is 580A. After melting 10 times, the sample should be turned over between every two meltings to ensure the uniformity of the sample. There should be at least a 5-minute interval between every two meltings to ensure that the temperature of the water-cooled crucible does not become too high and soften or break, causing danger. At the end of the last melting, quickly reduce the current and turn it off to ensure that the sample does not have any dents. Turn off the power and cool for 10 minutes. Open the vacuum valve and open the furnace door to obtain a smooth, uniformly shaped disc structure sample.

[0050] Step 4: Place the arc-melted sample in a high-vacuum, high-temperature furnace, and use a mechanical pump and a diffusion pump to bring the furnace pressure to 1×10⁻⁶. -3 After Pa, the sample was annealed by heating from room temperature to 1600℃ at a heating rate of 10℃ / min and holding for 15 hours. Then, it was cooled to room temperature in the furnace to obtain the Ta-W-Hf alloy.

[0051] Example 6

[0052] Step 1: Mix 78% Ta particles, 18% W powder and 4% Hf particles evenly by mass percentage to obtain tantalum alloy raw material. The purity of Ta particles, W powder and Hf particles is greater than 99.95%.

[0053] Step 2: Melt using a non-consumable electrode arc furnace. Turn on the cooling water, open the vent valve and furnace door. Wipe the copper crucible area with 20% hydrochloric acid and ethanol. After cleaning, place the tantalum alloy raw material in the water-cooled crucible of the non-consumable electrode arc furnace. After closing the furnace door, close the vent valve (also known as the vacuum valve). Turn on the mechanical pump to evacuate to 20 Pa to create a suitable environment for the molecular pump. Then, open the molecular pump and its two control valves to achieve a vacuum of 6 × 10⁻⁶ Pa inside the furnace. -3 After Pa, close the vacuum gauge, molecular pump and its near-furnace valve (high valve), and at the same time open the argon valve to fill the furnace with argon. When the furnace pressure reaches 0.05 MPa, close the argon valve. After the molecular pump speed drops to 0, close the far-furnace valve (diffusion valve) of the molecular pump and the mechanical pump.

[0054] Step 3: Place the tungsten needle 3mm directly above the titanium ball to start arc melting of the titanium ball. The melting current is 340A. This further absorbs the residual oxygen in the furnace cavity and also serves to check the sealing of the furnace body. Next, place the tungsten needle 3mm directly above the tantalum alloy raw material, turn on the electromagnetic stirring system, and start arc melting. The melting current is 520A. After melting 10 times, the sample should be turned over between every two meltings to ensure the uniformity of the sample. There should be at least a 5-minute interval between every two meltings to ensure that the temperature of the water-cooled crucible does not become too high and soften or break, causing danger. At the end of the last melting, quickly reduce the current and turn it off to ensure that the sample does not have any depressions. Turn off the power and cool for 12 minutes. Open the vacuum valve and open the furnace door to obtain a smooth, uniformly shaped disc structure sample.

[0055] Step 4: Place the arc-melted sample in a high-vacuum, high-temperature furnace, and use a mechanical pump and a diffusion pump to bring the furnace pressure to 2 × 10⁻⁶. -3 After Pa, the sample was annealed by heating from room temperature to 1600℃ at a heating rate of 10℃ / min and holding for 15 hours. Then, it was cooled to room temperature in the furnace to obtain the Ta-W-Hf alloy.

[0056] This invention utilizes a non-consumable electrode arc melting method to prepare ultra-high temperature alloys of this system in the laboratory, followed by prolonged high-temperature annealing to ultimately obtain a Ta-W-Hf system of ultra-high temperature high-strength tantalum alloys. The results show that the solid solution of Hf into the Ta-W alloy significantly enhances the material's strength at room temperature. The yield strength of Ta-20W-5Hf in room temperature compression tests reaches 1032 MPa, while maintaining over 40% of the compressive strain. In high-temperature compression tests at 2000℃, the yield strength reaches 340 MPa, demonstrating excellent high-temperature strength. This invention employs a non-consumable electrode arc melting and high-temperature annealing method, which has the advantages of simple equipment requirements, easily achievable experimental conditions, and relatively low cost. It enables the exploration and development of new Ta-based alloy systems in the laboratory, and the obtained Ta-W-Hf alloys exhibit excellent room-temperature and high-temperature mechanical properties.

Claims

1. A method for preparing an ultra-high temperature high-strength tantalum alloy, characterized in that... Includes the following steps: Step 1: Mix 75-80% Ta particles, 15-20% W powder and 1-5% Hf particles evenly by mass percentage to obtain tantalum alloy raw material; Step 2: Place the tantalum alloy raw material in the water-cooled crucible of the non-consumable electrode arc furnace. After closing the furnace door, close the venting valve (i.e., the vacuum breaking valve), turn on the mechanical pump to evacuate to 20 Pa, and then open the molecular pump and its two control valves to achieve a vacuum level of 2 × 10⁻⁶ Pa inside the furnace. -3 Pa ~ 6×10 -3 After Pa, close the vacuum gauge, molecular pump and its near-furnace valve (high valve), and at the same time open the argon valve to fill the furnace with argon. When the furnace pressure reaches 0.04~0.05 MPa, close the argon valve. After the molecular pump speed drops to 0, close the far-furnace valve (diffusion valve) of the molecular pump and the mechanical pump. Step 3: Place the tungsten needle 3-5mm directly above the titanium ball to start arc melting of the titanium ball. The melting current is 300-350A. Then place the tungsten needle 3-5mm directly above the tantalum alloy raw material, turn on the electromagnetic stirring system, start arc melting, and the melting current is 500-600A. After melting 10 times, turn off the power and cool for 10-15 minutes. Open the vacuum valve and open the furnace door to obtain a smooth surface and uniformly shaped disc structure sample. To ensure sample uniformity, the sample should be flipped between each melting process, and there should be at least a 5-minute interval between each melting process. Step 4: Place the arc-melted sample in a high-vacuum, high-temperature furnace, and use a mechanical pump and a diffusion pump to bring the furnace pressure to 1×10⁻⁶. -3 Pa~5×10 -3 After Pa, the sample was annealed by heating from room temperature to 1600℃ at a heating rate of 10℃ / min and holding for 15 hours. Then, it was cooled to room temperature in the furnace to obtain the Ta-W-Hf alloy.

2. The method for preparing ultra-high temperature high-strength tantalum alloy according to claim 1, characterized in that: In step 1, the purity of Ta particles, W powder and Hf particles is greater than 99.95%.

3. The method for preparing ultra-high temperature high-strength tantalum alloy according to claim 1, characterized in that: Before melting in the non-consumable electrode arc furnace in step 2, turn on the cooling water, open the vent valve and open the furnace door, wipe the copper crucible station with 20% hydrochloric acid and ethanol, and put in the tantalum alloy raw material prepared in step 1 after cleaning.

4. A high-temperature, high-strength tantalum alloy prepared by the method according to any one of claims 1 to 3, characterized in that: Ta-W-Hf alloys exhibit a typical single-phase BCC structure.

5. A high-temperature, high-strength tantalum alloy prepared by the method according to any one of claims 1 to 3, characterized in that: The Ta-W-Hf alloys exhibit a yield strength of 822~1032 MPa in room temperature compression tests, and the material retains more than 40% of its compressive strain.

6. A high-temperature, high-strength tantalum alloy prepared by the method according to any one of claims 1 to 3, characterized in that: The yield strength of the Ta-20wt%W-5wt%Hf alloy in the ultra-high temperature compression test at 2000℃ is 340 MPa.

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