A high-toughness ZrNbTa-based refractory high-entropy alloy and a preparation method thereof

Abstract

This invention relates to a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy and its preparation method, belonging to the field of metallic materials technology. The atomic percentage expression of the refractory high-entropy alloy is denoted as Zr. a Nb b Ta c M d M is one or more of Al, Fe, Co, Cr, Ni, Cu, Mg, Be, Si, C, O, N, B, and rare earth elements, with 10≤a≤50, 15≤b≤53, 17≤c≤60, 0≤d≤15, a≠b≠c, 50≤b+c≤80, c≥b / 2, and a+b+c+d=100; the high-entropy alloy is a double BCC phase with a modulus mismatch ≥0.274. By optimizing the alloy composition, a high modulus mismatch is achieved, and the microstructure is controlled to obtain a double BCC structure, thereby achieving both high strength and high uniform deformation capability.

Description

Technical Field

[0001] This invention relates to a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy and its preparation method, belonging to the field of metallic materials technology. Background Technology

[0002] High-entropy alloys typically consist of five or more major elements, with the molar fraction of each major element maintained between 5% and 35%. The content of minor elements generally does not exceed 5%. High-entropy alloys utilize a combination of metallic elements, selectively adding and controlling the proportions according to desired performance requirements, thereby achieving improvements in the alloy's mechanical properties and regulation of its physical properties. The mechanical properties exhibited by high-entropy alloys, such as high strength and high toughness, have attracted widespread attention in the industrial manufacturing field.

[0003] Refractory high-entropy alloys refer to high-entropy alloys with refractory metallic elements as the main components. These refractory metallic elements primarily include high-melting-point (>1650℃) metallic elements such as Ti, Zr, V, Nb, Hf, Ta, and W. Refractory high-entropy alloys typically maintain high high-temperature strength and hardness while also exhibiting good oxidation and corrosion resistance. These advantageous properties make them promising candidates for key components in high-temperature environments such as aerospace and energy sectors, and they are considered promising candidates for next-generation high-temperature alloys. However, refractory high-entropy alloys generally lack the ability to deform uniformly at room temperature. CN115386774A discloses a ZrHfVNbTa-based refractory high-entropy alloy, which improves the uniform deformation capability of the refractory high-entropy alloy through deformation-induced martensitic phase transformation; however, this alloy suffers from a low yield strength (450MPa), severely limiting its application. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy and its preparation method. By optimizing the alloy's composition, a high modulus mismatch is achieved, and the microstructure is controlled to obtain a double BCC structure, thereby achieving both high strength and high uniform deformation capability.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows.

[0006] A high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy, wherein the atomic percentage expression of the refractory high-entropy alloy is denoted as Zr a Nb b Ta c M dM is one or more of Al, Fe, Co, Cr, Ni, Cu, Mg, Be, Si, C, O, N, B and rare earth elements, 10≤a≤50, 15≤b≤53, 17≤c≤60, 0≤d≤15, a≠b≠c, 50≤b+c≤80, c≥b / 2, and a+b+c+d=100; the high-entropy alloy is a double BCC phase with a modulus mismatch ≥0.274.

[0007] Preferably, the dual BCC phases are TaZr phase and TaNb phase, respectively.

[0008] Preferably, 20≤a≤45, 25≤b≤50, 25≤c≤55, and 0≤d≤5.

[0009] Preferably, 60≤b+c≤75.

[0010] Preferably, M is one or more of Al, Fe, Cr, and Cu.

[0011] Preferably, the refractory high-entropy alloy has a yield strength of 800–1100 MPa, a tensile strength of 900–1250 MPa, a uniform elongation of 6%–18%, and a fracture strain of 20%–35%.

[0012] A method for preparing a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy according to the present invention includes the following steps:

[0013] Using metallic elements Zr, Nb, Ta, and M as raw materials, alloying and smelting are first carried out under an inert protective gas atmosphere to obtain a uniform refractory high-entropy alloy ingot. Then, the ingot is held at 50–200°C below the BCC matrix phase transformation temperature for 12–24 hours and cooled to obtain a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy.

[0014] Preferably, an electric arc melting furnace is used for alloying smelting.

[0015] Preferably, the alloying and melting process is carried out 3 to 5 times.

[0016] Preferably, the inert protective gas is argon.

[0017] Beneficial effects

[0018] This invention provides a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy. By controlling the proportions of Zr, Nb, and Ta elements to generate large atomic size mismatches, it promotes amplitude modulation decomposition, thereby obtaining a refractory high-entropy alloy with a dual-toughness BCC structure. High uniform elongation is obtained by utilizing the coordinated deformation of the two phases. At the same time, by controlling the content of the high-modulus element Ta, the modulus mismatch degree of the high-entropy alloy is ensured to be above 0.27. Ultimately, the highest uniform elongation of the refractory high-entropy alloy can reach more than 30%, while also possessing high tensile strength (the highest tensile strength can exceed 1100 MPa) and yield strength of more than 950 MPa.

[0019] This invention provides a method for preparing a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy. The preparation process of this refractory high-entropy alloy is simple, the raw materials are easy to obtain, and it is easy to realize industrial production. This is conducive to promoting the engineering application of refractory high-entropy alloys in aerospace, automotive, advanced manufacturing, new energy and other fields. Attached Figure Description

[0020] Figure 1 Zr prepared in Example 1 27 Nb 37 Ta 36 Optical microscope image of the grain boundaries of a refractory high-entropy alloy.

[0021] Figure 2 Zr prepared in Example 1 27 Nb 37 Ta 36 X-ray diffraction (XRD) pattern of a refractory high-entropy alloy.

[0022] Figure 3 Zr prepared in Example 1 27 Nb 37 Ta 36 Surface distribution of energy dispersive spectroscopy (EDS) of refractory high-entropy alloys.

[0023] Figure 4 Zr prepared in Example 1 27 Nb 37 Ta 36 Engineering stress-strain curves of quasi-static tensile stress in refractory high-entropy alloys. Detailed Implementation

[0024] To facilitate understanding of the present invention, the invention will be described more fully and in detail below with reference to the accompanying drawings and preferred embodiments, but the scope of protection of the present invention is not limited to the following specific embodiments.

[0025] Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention.

[0026] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0027] In the following examples and comparative examples:

[0028] (1) The main reagents used are shown in Table 1 below.

[0029] Table 1

[0030]

[0031] (2) Material preparation, performance testing and structural characterization

[0032] High vacuum arc melting-tilting casting system: manufactured by Shenyang Haozhiduo New Material Preparation Technology Co., Ltd.

[0033] Metallographic analysis: The metallographic structure of the prepared refractory high-entropy alloy was observed using a German Zeiss Axio observer A1m metallographic microscope. The material was first mounted using a hot mounting machine, then polished sequentially with 400#, 800#, 1200#, 2000#, 3000#, 5000#, and 7000# sandpaper, then polished with a silica suspension, and finally immersed in an etchant prepared by mixing 40% HF, 65%–68% HNO3 and H2O in a volume ratio of 1:3:40 for 2–30 seconds to prepare a sample for metallographic analysis.

[0034] Phase analysis: The X-ray diffraction patterns of the high-entropy alloy were determined using a Bruker AXS D8 advance X-ray diffractometer (Germany). The instrument's scanning angle range was 20–100°, using Cu target Kα rays. The operating voltage was 40 kV, the operating current was 40 mA, the scanning speed was 0.2 sec / step, the step size was 0.02° / step, and the measurement angle error was less than 0.01°.

[0035] Elemental analysis: High-entropy alloys were subjected to EDS energy dispersive spectroscopy analysis using a Hitachi S4800 cold field emission scanning electron microscope to analyze the elemental composition in different phase structures.

[0036] Quasi-static tensile mechanical property testing: A quasi-static tensile test at room temperature was conducted using a CMT4305 microcomputer-controlled universal testing machine, according to standard GB / T228.1-2010, with a strain rate of 10. -3 s -1 The test specimen was a non-standard I-shaped part, 1.0 mm thick, 3.14 mm wide, with a parallel section length of 10 mm and a gauge length of 5 mm. The mechanical properties such as tensile strength and uniform elongation were obtained based on the engineering stress-strain curve. Among them, tensile strength is the maximum engineering stress that the refractory high entropy alloy can bear, and uniform elongation is the engineering strain value corresponding to the load of the refractory high entropy alloy reaching the tensile strength.

[0037] Example 1

[0038] In this embodiment, the refractory high-entropy alloy comprises 27% Zr, 37% Nb, and 36% Ta by atomic percentage.

[0039] The preparation method of the refractory high-entropy alloy in this embodiment includes the following steps:

[0040] Zr, Nb, and Ta blocks with a purity greater than 99.9% were used as raw materials. First, the oxide scale on the surface of the elemental raw materials was removed by grinding with a grinding wheel, followed by ultrasonic cleaning with anhydrous ethanol. The raw materials were placed in an electric arc melting furnace at a ratio of 27% Zr, 37% Nb, and 36% Ta, arranged in order of increasing melting point. The vacuum was then reduced to 2.5 × 10⁻⁶. -3 The furnace is charged with argon gas at 0.6 atmospheres and then smelted. Before smelting, the Ti ingot is melted to absorb oxygen. After each smelting cycle, the furnace is allowed to cool before the next smelting cycle. Before the next smelting cycle, the ingot is flipped over, and then the titanium ingot is melted to absorb oxygen, repeating the previous steps. This arc smelting process is repeated five times, ensuring the ingot is fully melted each time. Magnetic stirring is added during the third and fourth smelting cycles to obtain a uniformly structured Zr. 27 Nb 37 Ta 36 High-entropy alloy ingot. Zr 27 Nb 37 Ta 36 The high-temperature BCC matrix phase transformation temperature of high-entropy alloys is 1305℃.

[0041] A high-entropy alloy ingot was sealed in a quartz tube filled with argon gas and held at 1250℃ for 24 hours to obtain Zr containing a two-phase structure. 27 Nb 37 Ta 36 Refractory high-entropy alloys.

[0042] For Zr 27 Nb 37 Ta36 Microstructure characterization of refractory high-entropy alloys, based on Figure 1 The characterization results show that the alloy has an equiaxed crystal structure, with coarse precipitates present at the grain boundaries and within the grains, and the precipitates are continuously distributed.

[0043] For Zr 27 Nb 37 Ta 36 Phase analysis of refractory high-entropy alloys was performed based on... Figure 2 The characterization results show that the alloy possesses two BCC phases. Combined with... Figure 3 The EDS energy spectrum shows that phase BCC1 is a TaZr-rich phase and phase BCC2 is a TaNb-rich phase, both of which are tough phases.

[0044] For Zr 27 Nb 37 Ta 36 Quasi-static tensile tests were conducted on refractory high-entropy alloys, based on... Figure 4 The test results show that the alloy has a tensile strength of 1040 MPa, a yield strength of 998 MPa, a uniform elongation of 11.5%, and a fracture strain of 31.2%, exhibiting obvious work hardening.

[0045] Example 2

[0046] In this embodiment, the refractory high-entropy alloy comprises 45% Zr, 35% Nb, and 25% Ta by atomic percentage.

[0047] The preparation method of the refractory high-entropy alloy in this embodiment includes the following steps:

[0048] Zr, Nb, and Ta blocks with a purity greater than 99.9% were used as raw materials. First, the oxide scale on the surface of the elemental raw materials was removed by grinding with a grinding wheel, followed by ultrasonic cleaning with anhydrous ethanol. The raw materials were placed in an electric arc melting furnace at a ratio of 45% Zr, 35% Nb, and 25% Ta, arranged in order of increasing melting point. The vacuum was then reduced to 2.5 × 10⁻⁶. -3 The furnace is charged with argon gas at 0.6 atmospheres and then smelted. Before smelting, the Ti ingot is melted to absorb oxygen. After each smelting cycle, the furnace is allowed to cool before the next smelting cycle. Before the next smelting cycle, the ingot is flipped over, and then the titanium ingot is melted to absorb oxygen, repeating the previous steps. This arc smelting process is repeated five times, ensuring the ingot is fully melted each time. Magnetic stirring is added during the third and fourth smelting cycles to obtain a uniformly structured Zr. 45 Nb 35 Ta 25 High-entropy alloy ingot. Zr 45 Nb 35 Ta 25The high-temperature BCC matrix phase transformation temperature of high-entropy alloys is 1317℃.

[0049] A high-entropy alloy ingot was sealed in a quartz tube filled with argon gas and held at 1150℃ for 12 hours to obtain Zr containing a two-phase structure. 45 Nb 35 Ta 25 Refractory high-entropy alloys.

[0050] For Zr 45 Nb 35 Ta 25 The microstructure of the refractory high-entropy alloy was characterized. According to the characterization results, the alloy has an equiaxed crystal structure with coarse precipitates at the grain boundaries and within the grains, and the precipitates are continuously distributed.

[0051] For Zr 45 Nb 35 Ta 25 Phase analysis of the refractory high-entropy alloy revealed that it possesses two BCC phases: BCC1 is a TaZr-rich phase, and BCC2 is a TaNb-rich phase. Both phases are ductile phases.

[0052] For Zr 45 Nb 35 Ta 25 A quasi-static tensile test was conducted on the refractory high-entropy alloy. According to the test results, the alloy has a tensile strength of 945 MPa, a yield strength of 895 MPa, a uniform elongation of 6.8%, and a fracture strain of 23.7%.

[0053] Example 3

[0054] In this embodiment, the refractory high-entropy alloy comprises, by atomic percentage, 25% Zr, 25% Nb, and 50% Ta.

[0055] The preparation method of the refractory high-entropy alloy in this embodiment includes the following steps:

[0056] Zr, Nb, and Ta blocks with a purity greater than 99.9% were used as raw materials. First, the oxide scale on the surface of the elemental raw materials was removed by grinding with a grinding wheel, followed by ultrasonic cleaning with anhydrous ethanol. The raw materials were placed in an electric arc melting furnace at a ratio of 25% Zr, 25% Nb, and 50% Ta, arranged in order of increasing melting point. The vacuum was then reduced to 2.5 × 10⁻⁶. -3The furnace is charged with argon gas at 0.6 atmospheres and then smelted. Before smelting, the Ti ingot is melted to absorb oxygen. After each smelting cycle, the furnace is allowed to cool before the next smelting cycle. Before the next smelting cycle, the ingot is flipped over, and then the titanium ingot is melted to absorb oxygen, repeating the previous steps. This arc smelting process is repeated five times, ensuring the ingot is fully melted each time. Magnetic stirring is added during the third and fourth smelting cycles to obtain a uniformly structured Zr. 25 Nb 25 Ta 50 High-entropy alloy ingot. Zr 25 Nb 25 Ta 50 The high-temperature BCC matrix phase transformation temperature of high-entropy alloys is 1325℃.

[0057] A high-entropy alloy ingot was sealed in a quartz tube filled with argon gas and held at 1200℃ for 12 hours to obtain Zr containing a two-phase structure. 25 Nb 25 Ta 50 Refractory high-entropy alloys.

[0058] For Zr 25 Nb 25 Ta 50 The microstructure of the refractory high-entropy alloy was characterized. According to the characterization results, the alloy has an equiaxed crystal structure with coarse precipitates at the grain boundaries and within the grains, and the precipitates are continuously distributed.

[0059] For Zr 25 Nb 25 Ta 50 Phase analysis of the refractory high-entropy alloy revealed that it possesses two BCC phases: BCC1 is a TaZr-rich phase, and BCC2 is a TaNb-rich phase. Both phases are ductile phases.

[0060] For Zr 25 Nb 25 Ta 50 A quasi-static tensile test was conducted on the refractory high-entropy alloy. According to the test results, the alloy has a tensile strength of 1140 MPa, a yield strength of 1060 MPa, a uniform elongation of 11.4%, and a fracture strain of 24.3%.

[0061] Example 4

[0062] In this embodiment, the refractory high-entropy alloy comprises, by atomic percentage, 30% Zr, 36% Nb, 32% Ta, and 2% Al.

[0063] The preparation method of the refractory high-entropy alloy in this embodiment includes the following steps:

[0064] Zr, Nb, Ta, and Al blocks, each with a purity greater than 99.9%, were used as raw materials. The oxide scale on the surface of the elemental raw materials was first removed by grinding with a grinding wheel, followed by ultrasonic cleaning with anhydrous ethanol. The raw materials were placed in an electric arc melting furnace at a ratio of 30% Zr, 36% Nb, 32% Ta, and 2% Al, arranged in order of increasing melting point. The vacuum was then reduced to 2.5 × 10⁻⁶. -3 The furnace is charged with argon gas at 0.6 atmospheres and then smelted. Before smelting, the Ti ingot is melted to absorb oxygen. After each smelting cycle, the furnace is allowed to cool before the next smelting cycle. Before the next smelting cycle, the ingot is flipped over, and then the titanium ingot is melted to absorb oxygen, repeating the previous steps. This arc smelting process is repeated five times, ensuring the ingot is fully melted each time. Magnetic stirring is added during the third and fourth smelting cycles to obtain a uniformly structured Zr. 30 Nb 36 Ta 32 Al2 high-entropy alloy ingot. Zr 30 Nb 36 Ta 32 The high-temperature BCC matrix phase transformation temperature of Al2 high-entropy alloy is 1440℃.

[0065] A high-entropy alloy ingot was sealed in a quartz tube filled with argon gas and held at 1250℃ for 12 hours to obtain Zr containing a two-phase structure. 30 Nb 36 Ta 32 Al2 refractory high-entropy alloy.

[0066] For Zr 30 Nb 36 Ta 32 The microstructure of the Al2 refractory high-entropy alloy was characterized. According to the characterization results, the alloy has an equiaxed crystal structure with coarse precipitates at the grain boundaries and within the grains, and the precipitates are continuously distributed.

[0067] For Zr 30 Nb 36 Ta 32 Phase analysis of the Al2 refractory high-entropy alloy revealed that the alloy has two BCC phases: BCC1 is a TaZr-rich phase, and BCC2 is a TaNb-rich phase. Both phases are ductile phases.

[0068] For Zr 30 Nb 36 Ta 32 Quasi-static tensile tests were conducted on Al2 refractory high-entropy alloys. The test results showed that the alloy had a tensile strength of 1037 MPa, a yield strength of 835 MPa, a uniform elongation of 7.2%, and a fracture strain of 26.3%.

[0069] Comparative Example 1

[0070] Based on Example 1, the smelted alloy ingot was placed in a vacuum quenching furnace and held at 1450°C for 6 hours. All other steps and conditions were the same as in Example 1, resulting in a solution-treated Zr. 27 Nb 37 Ta 36 Refractory high-entropy alloys.

[0071] For Zr 27 Nb 37 Ta 36 The microstructure of the refractory high-entropy alloy was characterized. According to the characterization results, the alloy has an equiaxed crystal structure, and no precipitated phases appear at the grain boundaries or within the grains.

[0072] For Zr 27 Nb 37 Ta 36 Phase analysis of the refractory high-entropy alloy revealed that it has a single-phase BCC structure.

[0073] For Zr 27 Nb 37 Ta 36 A quasi-static tensile test was conducted on the refractory high-entropy alloy. According to the test results, the tensile strength of the alloy is 840 MPa, the yield strength is 720 MPa, and the fracture strain is 4.8%.

[0074] Comparative Example 2

[0075] The refractory high-entropy alloy in this comparative example contains, by atomic percentage, 15% Zr, 30% Nb, and 55% Ta.

[0076] The preparation method of this comparative refractory high-entropy alloy includes the following steps:

[0077] Zr, Nb, and Ta blocks, all with a purity greater than 99.9%, were used as raw materials. First, the oxide scale on the surface of the elemental raw materials was removed by grinding with a grinding wheel, followed by ultrasonic cleaning with anhydrous ethanol. The raw materials were placed in an electric arc melting furnace at a ratio of 15% Zr, 30% Nb, and 55% Ta, arranged in order of increasing melting point. The furnace was then evacuated to a vacuum level of 2.5 × 10⁻⁶. -3 The furnace is charged with argon gas at 0.6 atmospheres and then smelted. Before smelting, the Ti ingot is melted to absorb oxygen. After each smelting cycle, the furnace is allowed to cool before the next smelting cycle. Before the next smelting cycle, the ingot is flipped over, and then the titanium ingot is melted to absorb oxygen, repeating the previous steps. This arc smelting process is repeated five times, ensuring the ingot is fully melted each time. Magnetic stirring is added during the third and fourth smelting cycles to obtain a uniformly structured Zr. 15 Nb 30 Ta55 High-entropy alloy ingot. Zr 15 Nb 30 Ta 55 The high-temperature BCC matrix phase transformation temperature of high-entropy alloys is 1176℃.

[0078] A high-entropy alloy ingot was sealed in a quartz tube filled with argon gas and held at 1100℃ for 12 hours to obtain Zr. 15 Nb 30 Ta 55 Refractory high-entropy alloys.

[0079] For Zr 15 Nb 30 Ta 55 The microstructure of the refractory high-entropy alloy was characterized. According to the characterization results, the alloy has an equiaxed crystal structure and no obvious second phase appears.

[0080] For Zr 15 Nb 30 Ta 55 Phase analysis of the refractory high-entropy alloy revealed that it has a single-phase BCC structure.

[0081] For Zr 15 Nb 30 Ta 55 A quasi-static tensile test was conducted on the refractory high-entropy alloy. According to the test results, the tensile strength of the alloy is 620 MPa, the yield strength is 530 MPa, and the fracture strain is 3.7%.

[0082] In summary, the invention includes, but is not limited to, the above embodiments. Any equivalent substitutions or partial improvements made under the spirit and principles of this invention shall be considered to be within the protection scope of this invention.

Claims

1. A high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy, characterized in that: The atomic percentage expression for the refractory high-entropy alloy is denoted as Zr. a Nb b Ta c M d M is one or more of Al, Fe, Co, Cr, Ni, Cu, Mg, Be, Si, C, O, N, B, and rare earth elements, 10≤a≤50, 15≤b≤53, 17≤c≤60, 0≤d≤15, a≠b≠c, 50≤b+c≤80, c≥b / 2, and a+b+c+d=100; the high-entropy alloy is a double BCC phase with a modulus mismatch ≥0.274; The dual BCC phases are TaZr phase and TaNb phase, respectively; The refractory high-entropy alloy is prepared by the following method, the steps of which include: using metallic elements Zr, Nb, Ta and M as raw materials, alloying and melting are first carried out under an inert protective gas atmosphere to obtain a refractory high-entropy alloy ingot with uniform microstructure, and then holding at 50~200℃ below the BCC parent phase transformation temperature for 12~24 h, and then cooling to obtain a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy.

2. The high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy as described in claim 1, characterized in that: 20≤a≤45, 25≤b≤50, 25≤c≤55, 0≤d≤5.

3. The high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy as described in claim 1, characterized in that: 60≤b+c≤75.

4. The high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy as described in claim 1, characterized in that: M is one or more of Al, Fe, Cr, and Cu.

5. A high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy as described in any one of claims 1 to 4, characterized in that: The refractory high-entropy alloy has a yield strength of 800~1100MPa, a tensile strength of 900~1250MPa, a uniform elongation of 6%~18%, and a fracture strain of 20%~35%.

6. A method for preparing a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy as described in any one of claims 1 to 5, characterized in that: The method steps include: Using metallic elements Zr, Nb, Ta, and M as raw materials, alloying and smelting are first carried out under an inert protective gas atmosphere to obtain a uniform refractory high-entropy alloy ingot. Then, the ingot is held at 50~200℃ below the BCC parent phase transformation temperature for 12~24 h and cooled to obtain a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy.

7. The method for preparing a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy as described in claim 6, characterized in that: Alloying smelting was carried out using an electric arc melting furnace.

8. The method for preparing a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy as described in claim 6, characterized in that: Alloying and melting 3 to 5 times.

9. The method for preparing a high-strength and high-toughness ZrNbTa-based refractory high-entropy alloy as described in claim 6, characterized in that: The inert protective gas is argon.

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