A non-equi-molar ratio high-performance high-entropy material, a preparation method and application thereof

Abstract

This invention discloses a non-equimolar ratio high-performance high-entropy material, its preparation method, and its application. The high-entropy material, by mass percentage, comprises: Nb: 44.91~45.45%, Ti: 23.02%~23.53%, Cr: 12.13%~12.62%, V: 12.39%~12.87%, and Al: 6.31%~6.83%. The preparation method is as follows: S1, placing an Al-containing master alloy, Nb, Ti, Cr, and V in a vacuum arc furnace and repeatedly melting them 7~8 times; the Al-containing master alloy is placed in the lower layer, and Nb, Ti, Cr, and V are placed in the upper layer; S2, placing the melted alloy block in a vacuum heat treatment furnace for vacuum homogenization heat treatment to obtain a high-entropy alloy with high toughness and low-temperature superconductivity. This high-entropy alloy has a single-phase BCC solid solution structure, which has higher plasticity and strength compared with traditional commercial low-temperature superconductors. It is easy to mold and use, and the preparation method is simple, reducing production and application costs. It can be applied to aerospace low-temperature superconducting devices, quantum computing equipment, superconducting magnets for nuclear fusion devices and other fields, and has important scientific research value and application prospects.

Description

Technical Field

[0001] This invention relates to the field of superconducting materials technology, and more specifically, to a non-equimolar ratio high-performance high-entropy material, its preparation method, and its application. Background Technology

[0002] Superconducting materials at critical temperature (T c Superconducting materials simultaneously exhibit unique macroscopic quantum phenomena such as zero resistance, perfect diamagnetism, and quantum tunneling. Since their initial discovery in mercury in 1911, superconducting materials have consistently garnered significant attention from the scientific community due to their unique advantages, including lossless transmission of large currents and generation of strong magnetic fields. Commercially available low-temperature superconducting materials have become indispensable core materials in fields such as energy, medicine, quantum physics, and aerospace. They demonstrate irreplaceable application value in key scenarios such as nuclear magnetic resonance imaging (MRI), controlled nuclear fusion, particle accelerators, and superconducting power transmission.

[0003] High-entropy alloys are novel alloy systems composed of multiple principal elements. Through high-entropy effects, lattice distortion effects, slow diffusion effects, and cocktail effects, they can form stable single-phase solid solution structures, typically exhibiting both high strength and good ductility. The high strength of high-entropy alloys leads to high structural stability within the system, and they also exhibit excellent properties in mechanical properties, corrosion resistance, and low-temperature stability, providing a new approach for the development of novel low-temperature superconducting materials.

[0004] Patent application CN202511503954.9 discloses a tough niobium-titanium alloy material, its preparation method, and its application in the fabrication of central conductors. Through double vacuum melting, two-stage pre-homogenization heat treatment, gradient-controlled thermomechanical processing, and two-stage aging heat treatment, a synergistic strengthening structure of fine-grained β matrix + dispersed α phase + nano-MC carbide is obtained, retaining 3-10% metastable β phase. This structure is suitable for fabricating central conductors of low-temperature superconducting wires. However, the process used in this patent application is complex and has stringent preparation requirements, resulting in high costs and difficulty in mass production. Furthermore, the types and proportions of each phase are difficult to control during the preparation process, leading to significant uncertainties.

[0005] Patent application CN202511053069.5 discloses an FCC-structured Mo-based medium-entropy carbide superconducting material and its preparation method. The method involves grinding and pressing Mo, Ir, and C in a stoichiometric ratio into blocks, followed by arc melting to synthesize a face-centered cubic (FCC) structured Mo3Ir2C polycrystalline bulk material with a superconducting transition temperature of 3.33 K. To further optimize the superconducting performance, Pt is used to partially replace Ir to produce Mo3IrPtC, achieving a transition temperature of 3.50 K. The material described in this patent is a medium-entropy carbide material, which, while possessing good structural stability, also exhibits significant brittleness, making it difficult to fabricate into superconducting wires or cables, thus hindering practical application.

[0006] Piotr Sobota et al. New type of Ti-rich HEA superconductors with highupper critical field. Acta Materialia. 2025, (Issue 285) Page 120666, Section 3, Preparation of Ti by Arc Melting. 0.5 (ZrNbHfTa) 0.5 The high-entropy alloy superconductor exhibits a high upper critical field. However, due to the use of elemental metals as additives, burn-off occurs during the smelting process, resulting in a significant difference between the designed additive amount and the final elemental composition. EDS results after smelting show severe elemental segregation. Elemental segregation significantly affects the material's mechanical properties, reducing its strength and toughness.

[0007] Therefore, low-temperature superconducting materials typically suffer from complex fabrication processes, stringent preparation requirements, and poor mechanical properties. High-entropy superconductors, due to their multi-principal element mixtures, exhibit differences in melting points, making them prone to burn-off during melting. The intrinsic differences between elements in multi-principal element alloys lead to severe elemental segregation, significantly impacting mechanical properties. Commercially available low-temperature superconductors are usually ceramic materials or synthetically prepared intermetallic compounds, exhibiting poor mechanical properties and hindering practical applications; they are often used in thin films or as cable cores. In traditional BCS theory, the superconducting performance of a superconductor is directly proportional to the structural stability within the system. Materials with high structural stability and strong bonding are typically hard and brittle ceramics and compound materials. Therefore, developing novel superconducting materials that balance superconductivity and mechanical properties while maintaining low cost remains a research hotspot and challenge in academia. Summary of the Invention

[0008] To address the aforementioned deficiencies in existing technologies, this invention provides a novel BCC-structured, high-toughness, high-entropy, low-temperature superconducting material. This material is prepared via arc melting, followed by homogenization heat treatment to ensure uniform microstructure. It exhibits a superconducting transition temperature of 4.73–4.94 K, a yield strength of at least 835 MPa, and an elongation at break of at least 35%, demonstrating potential for practical applications.

[0009] To achieve the above objectives, the present invention provides the following technical solution: In a first aspect, the present invention provides a non-equimolar ratio high-performance high-entropy material, denoted as (NbTi). 0.66 (CrVAl) 0.33 It comprises the following components by mass percentage: Nb: 44.91%~45.45%; Ti: 23.02%~23.53%; Cr: 12.13%~12.62%; V: 12.39%~12.87%; Al: 6.31%~6.83%.

[0010] In the preferred embodiment, the high-entropy alloy with high toughness and low-temperature superconductivity has a yield strength ≥835MPa, an ultimate tensile strength ≥945MPa, an elongation at break ≥35%, and a reduction of area ≥35%.

[0011] In the preferred embodiment, the superconducting transition temperature (Tc) of the high-entropy alloy with high toughness and low-temperature superconductivity is 4.73~4.94K, the upper critical field is ≥5.2T, and the lower critical field is ≥9.1mT.

[0012] A second aspect of the present invention provides a method for preparing a non-equimolar ratio high-performance high-entropy material, comprising the following steps: S1. Vacuum arc melting: An Al-containing master alloy, Nb, Ti, Cr, and V are placed in a vacuum electric arc furnace and repeatedly melted 7-8 times; the Al-containing master alloy is placed in the lower layer, and Nb, Ti, Cr, and V are placed in the upper layer. S2, Vacuum homogenization heat treatment: The alloy block obtained after melting in step S1 is placed in a vacuum heat treatment furnace for vacuum homogenization heat treatment to obtain a high-performance, high-entropy material with non-equimolar ratio.

[0013] In the preferred embodiment, in step S1, the Al-containing master alloy is AlV. 50 or AlCr 30 This is to avoid burning off the Al element during processing.

[0014] In the preferred embodiment, in step S1, the metal block containing Al master alloy is 4-8 mm in size, and the metal blocks containing Nb, Ti, Cr and V are each 3-6 mm in size.

[0015] In the preferred embodiment, the conditions for vacuum arc melting in step S1 are: a vacuum degree of 4 × 10⁻⁶. -3 ~5×10 -3 After evacuating the vacuum, fill with 0.3~0.5 atm of high-purity argon gas. The arc ignition current is 60~80A, the melting current is 110~140A, and the melting voltage is 20~25V. Note that the molten pool should be kept bright and stable with no obvious splashing.

[0016] More preferably, in step S1, the melting current for the first melting is 110~130A, the melting current for the second to sixth melting is 130~140A, and the melting current for the seventh to eighth melting is 110~120A.

[0017] In the preferred embodiment, in step S2, the vacuum homogenization heat treatment is performed at a vacuum degree of 5.0 × 10⁻⁶. -2 ~7.0×10 -3 Under a vacuum of Pa, the alloy is held at 1200~1300℃ for 12~16h, then furnace cooled to 400~500℃ and then air cooled to obtain a high-entropy alloy with high toughness and low-temperature superconductivity.

[0018] A third aspect of the present invention provides an application of a high-entropy alloy with high toughness and low-temperature superconductivity, which can be used in superconducting devices operating at temperatures of 4.94K and below.

[0019] Specifically, the above applications include at least one or more of the following: 1) Quantum computing devices; 2) Aerospace cryogenic superconducting equipment; 3) Superconducting coils for medical magnetic resonance imaging (MRI) equipment; 4) Superconducting magnet for nuclear fusion device.

[0020] It is understood that the present invention may be any one of the above-described embodiments or any combination of two or more non-conflicting embodiments.

[0021] The first key aspect of this invention is the design of the smelting process. Because the melting points of Al (933.47K) differ significantly from those of other elements (Nb: 2750K, Ti: 1941K, V: 2183K), an Al-containing master alloy, AlV, is selected as the smelting material. 50 or AlCr 30 To prevent Al burn-off during the smelting process, multiple stages of smelting are employed. In the first stage, to avoid defects caused by excessively rapid smelting, a small current is used for slow melting. In the second to sixth stages, a current of 130-140A is used to ensure sufficient smelting. In the seventh and eighth stages, the current is reduced to prevent severe Al burn-off due to the increased number of smelting stages.

[0022] The second key aspect of this invention is the use of vacuum homogenization heat treatment to ensure uniform material microstructure and stable performance. Vacuum heat treatment avoids severe high-temperature oxidation of Ti, Al, and Cr elements, which are prone to forming oxides within the system. This results in the preparation of (NbTi) with a uniform microstructure and virtually no oxidation. 0.66 (CrVAl) 0.33 High-entropy alloy bulk materials are used to obtain stable and reproducible preparation results, facilitating large-scale production in practice.

[0023] The third key aspect of this invention is the addition of V (5.3 K), an element with a high critical transition temperature, and Al and Cr, which enhance the material's plasticity, to NbTi as a base. Since BCC-structured solid solutions possess good structural stability, Nb, Ti, and V, the BCC-forming elements, and Al and Cr, the BCC-stabilizing elements, are selected to ensure a single-phase BCC structure. Based on Matthias's rule regarding the influence of VEC on superconducting properties, and combined with the control of element content, the overall composition was designed to achieve a (NbTi) with a mixing entropy of 1.55R and a valence electron concentration of 4.57. 0.66 (VCrAl) 0.33 High-entropy alloys. This ensures that high-entropy alloys possess good strength and ductility while also exhibiting good low-temperature superconductivity.

[0024] Compared with the prior art, the beneficial effects of the present invention are: 1) The (NbTi) prepared by this invention 0.66 (CrVAl) 0.33 Although the melting points of high-entropy alloys vary considerably within the system, there is no significant elemental segregation or Al burn-off, resulting in stable preparation results. High-entropy alloy bulks with BCC solid solution structures can be stably prepared.

[0025] 2) Vacuum heat treatment ensures a more uniform microstructure within the system and avoids the impact of oxides caused by atmospheric heat treatment on the superconducting and mechanical properties of the material. It allows for the more stable preparation of high-entropy alloy bulk materials with uniform microstructures, which is beneficial for consistent quality in large-scale production.

[0026] 3) The (NbTi) provided by this invention 0.66 (CrVAl) 0.33 High-entropy alloys have higher strength and plasticity, with a yield strength ≥835MPa, ultimate tensile strength ≥945MPa, elongation at break ≥35%, and reduction of area ≥35%.

[0027] 4) The (NbTi) provided by this invention 0.66 (CrVAl) 0.33 High-entropy alloys have simple preparation methods, which reduce production and application costs. Compared with other low-temperature superconductor materials, they have better mechanical properties, are easier to form and use, and are easier to use directly as superconducting wires and cables. Attached Figure Description

[0028] Figure 1 Example 1 is a high-entropy alloy (NbTi) exhibiting high toughness and low-temperature superconductivity. 0.66 (CrVAl) 0.33 SEM images and EDS elemental analysis images; Figure 2 Example 1 is a high-entropy alloy (NbTi) exhibiting high toughness and low-temperature superconductivity. 0.66 (CrVAl) 0.33 XRD patterns; Figure 3 Example 1 is a high-entropy alloy (NbTi) exhibiting high toughness and low-temperature superconductivity. 0.66 (CrVAl) 0.33 The resistivity and temperature (RT) curves; Figure 4 Example 1 is a high-entropy alloy (NbTi) exhibiting high toughness and low-temperature superconductivity. 0.66 (CrVAl) 0.33 RT curves under different magnetic fields and MH curves under 0-500 Oe conditions; Figure 5 Example 1 shows a high-performance, high-entropy material (NbTi) with a non-equimolar ratio. 0.66 (CrVAl) 0.33 The stress-strain curve. Detailed Implementation

[0029] The technical solution of the present invention will now be clearly and completely described with reference to specific embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. For those skilled in the art, other specific embodiments can be obtained based on these specific embodiments without creative effort.

[0030] Example 1

[0031] This embodiment exemplarily provides a non-equimolar ratio high-performance high-entropy material, which comprises the following components by mass percentage: Nb: 45.13%, Ti: 23.26%, Cr: 12.41%, V: 12.65%, Al: 6.73%.

[0032] Specifically, a method for preparing a non-equimolar ratio high-performance high-entropy material includes the following steps: S1. Vacuum arc melting: According to the composition ratio designed for the alloy, an Al-containing master alloy, Nb, Ti, Cr, and V were placed in a vacuum arc furnace and repeatedly melted eight times. The Al master alloy was placed in the lower layer, followed by the high-melting-point elemental metals Nb, Ti, Cr, and V. The Al-containing master alloy was AlV. 50 AlV 50 and AlCr 30 Metal blocks of 6 mm in size were used, while Nb, Ti, Cr, and V each used metal blocks of 5 mm in size. The vacuum arc melting conditions were: a vacuum degree of 5 × 10⁻⁶.-3 After evacuation, 0.5 atm of high-purity argon gas is introduced, and the arc ignition current is 80A. The eight melting processes are carried out in stages at different currents. The melting current for the first melting process is 110A and the melting voltage is 22V. It is important to keep the molten pool bright and stable with no obvious splashing. The melting current for the second to sixth melting processes is 140A and the melting voltage is 22V. The melting current for the seventh and eighth melting processes is reduced to 120A and the melting voltage is 22V.

[0033] S2, Vacuum homogenization heat treatment: The alloy block obtained after melting in step S1 is placed in a vacuum heat treatment furnace at 7.0 × 10⁻⁶. -3 Under a vacuum of Pa, the sample was held at 1200℃ for 15 hours, then furnace cooled to 450℃ and air cooled to obtain (NbTi). 0.66 (CrVAl) 0.33 .

[0034] Figure 1 Example 1 shows a high-performance, high-entropy material (NbTi) with a non-equimolar ratio. 0.66 (CrVAl) 0.33 SEM images and EDS elemental analysis images. (From...) Figure 1 It can be seen that (NbTi) is obtained through vacuum arc melting and vacuum homogenization heat treatment processes. 0.66 (CrVAl) 0.33 The alloy exhibits a uniform microstructure with no significant elemental segregation, and is dense with no porosity or obvious defects. The average grain size is 359.8 μm. Due to the extremely high melting point of this high-entropy alloy enriched in refractory elements, the slow cooling rate of the molten pool during as-cast solidification allows ample time for grains to preferentially grow and engulf smaller nuclei, ultimately forming relatively coarse grains. The large grains possess high lattice integrity, with a small number of subgrain boundaries dispersing stress. At high temperatures, grain boundaries soften and slip weakens, and the coarse grains actually enhance high-temperature creep and deformation resistance, resulting in good structural stability. Large-angle grain boundaries (>10°) dominate the microstructure of this alloy (accounting for 81.2%). Internal stress generated by solidification shrinkage during solidification causes some grains to undergo minute rotations, forming a small number of small-angle grain boundaries (2-10°) within the larger grains. During the solidification process of the alloy, the nucleation and growth of the molten pool exhibits the characteristic of random orientation growth of polycrystalline grains, with the orientation difference between grains generally exceeding 10°, ultimately forming large-angle grain boundaries that account for 81.2%. These large-angle grain boundaries have high interfacial energy and large lattice mismatch, which are typical characteristics of the primary microstructure of as-cast alloys. They can effectively block long-range dislocation slip, thereby obtaining a high-entropy alloy with both strength and toughness. (NbTi) 0.66 (CrVAl) 0.33High-entropy alloys possess coarse, uniform solid solution grains with no significant oligoprecipitates and low grain boundary density, which reduces electron scattering and improves the residual resistivity ratio (RRR). Furthermore, they optimize the electron-phonon coupling environment, facilitating the attainment of higher superconducting critical temperatures (T0). c It also exhibits good intrinsic properties of flux pinning.

[0035] Figure 2 Example 1 shows a high-performance, high-entropy material (NbTi) with a non-equimolar ratio. 0.66 (CrVAl) 0.33 XRD patterns. For example... Figure 2 As shown, (NbTi) 0.66 (CrVAl) 0.33 The high-entropy alloy is a single-phase solid solution with space group Im-3m (229). Its lattice parameter is 3.365 Å, and its preferred orientation plane is (110). The XRD patterns show shifts in the positions of diffraction peaks, with enhanced intensity at higher angles. This shift is due to lattice distortion caused by the different atomic radii of the multiple principal elements in the high-entropy alloy, as well as the preferred orientation in crystallography. The single-phase BCC structure exhibits good structural stability, leading to better superconductivity, and the lattice distortion allows the material to achieve a higher upper critical field and a higher critical current density.

[0036] Figure 3 Example 1 shows a high-performance, high-entropy material (NbTi) with a non-equimolar ratio. 0.66 (CrVAl) 0.33 The resistivity and temperature (RT) curves are shown. The RT curves reveal that above Tc, the temperature dependence of ρ(T) indicates that the metallic behavior increases linearly with increasing temperature. This linear behavior of ρ(T) may stem from the high degree of disorder in the compound. The resistivity at room temperature is 82.37 µΩ·cm, decreasing continuously with decreasing temperature. The resistivity under normal conditions conforms to the Bloch-Grüneisen equation. Fitting the Bloch-Grüneisen equation yields a residual resistivity of 73.27 µΩ·cm, obtained at the Debye temperature. It is 249.7 K. The superconducting critical transition temperature To c The K value is 4.94K, indicating that the material has good low-temperature superconducting properties.

[0037] Figure 4 Example 1 shows a high-performance, high-entropy material (NbTi) with a non-equimolar ratio. 0.66 (CrVAl) 0.33The RT curves under different magnetic fields and the MH curves under conditions of 0-500 Oe were obtained. The upper and lower critical field data of the material can be obtained by fitting the RT and MH curves using the GL equation. After fitting with the GL equation, the upper critical field of the material is found to be 5.49 T, and the lower critical field is 9.15 mT. This low-temperature superconducting material exhibits clearly defined upper and lower critical fields, classifying it as a Type II superconductor. Type II superconductors can maintain superconductivity under strong magnetic fields, supporting applications in MRI, accelerators, and nuclear fusion magnets. Under conditions ranging from 9.15 mT to 5.49 T, it functions as a mixed-state superconductor and does not exhibit quenching loss during use. The critical current density Jc of the material, obtained using the MH curve and the Bean model, is 1984 A / cm². 2 (T = 2K, H = 0.01T), exhibiting good current-carrying capacity.

[0038] Figure 5 Example 1 shows a high-performance, high-entropy material (NbTi) with a non-equimolar ratio. 0.66 (CrVAl) 0.33 The stress-strain curves show a yield strength of 836.58 MPa, an ultimate tensile strength of 948.37 MPa, an elongation at break of 38.1%, and a reduction of area of ​​40.1%. The material exhibits high strength and toughness. (NbTi) 0.66 (CrVAl) 0.33 To achieve both strength and high toughness in high-entropy low-temperature superconducting materials.

[0039] Example 2

[0040] This embodiment exemplarily provides a non-equimolar ratio high-performance high-entropy material, comprising the following components by weight percentage: Nb: 45.45%; Ti: 23.50%; Cr: 12.13%; V: 12.39%; Al: 6.75%.

[0041] Specifically, the preparation method of the non-equimolar ratio high-performance high-entropy material provided in this embodiment includes the following steps: S1. Vacuum arc melting: According to the composition ratio designed for the alloy, an Al-containing master alloy, Nb, Ti, Cr, and V were placed in a vacuum arc furnace and repeatedly melted eight times. The Al master alloy was placed in the lower layer, while the high-melting-point elemental metals Nb, Ti, Cr, and V were placed in the upper layer. The Al-containing master alloy was AlV. 50 AlV 50 and AlCr 30 Metal blocks of 4 mm in size were used, with Nb, Ti, Cr, and V each using 4 mm blocks. The vacuum arc melting conditions were: a vacuum degree of 5 × 10⁻⁶. -3After evacuation, high-purity argon gas at 0.45 atm is introduced, and the arc ignition current is 80A. The eight melting processes are carried out in stages under different currents and voltages. The melting current for the first melting process is 120A and the melting voltage is 23V. It is important to keep the molten pool bright and stable with no obvious splashing. The melting current for the second to sixth melting processes is 130A and the melting voltage is 25V. The melting current for the seventh and eighth melting processes is reduced to 110A and the melting voltage is 21V.

[0042] S2, Vacuum homogenization heat treatment: The alloy block obtained after melting in step S1 is placed in a vacuum heat treatment furnace at 5.0 × 10⁻⁶. -2 Under a vacuum of Pa, the material was held at 1300℃ for 13 hours, then furnace cooled to 400℃ and then air cooled to obtain a high-performance, high-entropy material with non-equimolar ratio.

[0043] The room temperature resistivity of the non-equimolar ratio high-performance high-entropy material prepared in Example 2 was measured to be 81.75 µΩ·cm. The residual resistivity obtained by fitting the Bloch-Grüneisen equation was 72.17 µΩ·cm, and the Debye temperature was [not specified in the original text]. It is 251.8 K. The superconducting critical transition temperature T0 c The critical temperature is 4.92 K. The upper critical field is 5.51 T, and the lower critical field is 9.73 mT. The yield strength is 837.92 MPa, the ultimate tensile strength is 951.45 MPa, the elongation at break is 39.3%, and the reduction of area is 41.5%.

[0044] Example 3

[0045] The mass percentages of each metallic element and the preparation process and conditions in the high-toughness and low-temperature superconductivity alloy prepared in this embodiment are exactly the same as in Example 1. The room-temperature resistivity of the non-equimolar ratio high-performance high-entropy material prepared in this embodiment is measured to be 81.75 µΩ·cm, and the residual resistivity obtained by fitting the Bloch-Grüneisen equation is 72.17 µΩ·cm. The Debye temperature... It is 251.8 K. The superconducting critical transition temperature T0 c The critical temperature is 4.92 K. The upper critical field is 5.48 T, and the lower critical field is 9.17 mT. The yield strength is 835.82 MPa, the ultimate tensile strength is 950.17 MPa, the elongation at break is 40.6%, and the reduction of area is 41.3%.

[0046] (NbTi) was prepared using the same raw material mass percentages and process parameters as in Example 1. 0.66 (CrVAl) 0.33 The superconductor's performance is similar to that of Example 1, and its stable production facilitates stable batch production.

[0047] Example 4

[0048] The mass percentages of each metallic element and the preparation process and conditions in the high-toughness and low-temperature superconductivity alloy prepared in this embodiment are exactly the same as in Example 2. The room-temperature resistivity of the non-equimolar ratio high-performance high-entropy material prepared in this embodiment was measured to be 81.77 µΩ·cm, and the residual resistivity obtained by fitting the Bloch-Grüneisen equation was 72.93 µΩ·cm. The Debye temperature... It is 250.3 K. The superconducting critical transition temperature T0 c The critical temperature is 4.93 K. The upper critical field is 5.50 T, and the lower critical field is 9.19 mT. The yield strength is 839.85 MPa, the ultimate tensile strength is 955.61 MPa, the elongation at break is 39.9%, and the reduction of area is 41.8%.

[0049] (NbTi) was prepared using the same raw material mass percentages and process parameters as in Example 2. 0.66 (CrVAl) 0.33 The superconductor's performance is similar to that of Example 2, and its stable production facilitates stable batch production.

[0050] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A non-equimolar ratio high-performance high-entropy material, characterized in that, By mass percentage, it includes the following components: Nb: 44.91%~45.45%; Ti: 23.02%~23.53%; Cr: 12.13%~12.62%; V: 12.39%~12.87%; Al: 6.31%~6.83%.

2. The high-performance, high-entropy material with non-equimolar ratio according to claim 1, characterized in that, Its yield strength is ≥835MPa, ultimate tensile strength is ≥945MPa, elongation at break is ≥35%, and reduction of area is ≥35%.

3. The high-performance, high-entropy material with non-equimolar ratio according to claim 1, characterized in that, Its superconducting transition temperature is 4.73~4.94K, the upper critical field is ≥5.2T, and the lower critical field is ≥9.1mT.

4. A method for preparing a non-equimolar ratio high-performance high-entropy material according to any one of claims 1 to 3, characterized in that, Includes the following steps: S1. Vacuum arc melting: An Al-containing master alloy, Nb, Ti, Cr, and V are placed in a vacuum electric arc furnace and repeatedly melted 7-8 times; the Al-containing master alloy is placed in the lower layer, and Nb, Ti, Cr, and V are placed in the upper layer. S2, Vacuum homogenization heat treatment: The alloy block obtained after melting in step S1 is placed in a vacuum heat treatment furnace for vacuum homogenization heat treatment to obtain a high-entropy alloy with high toughness and low-temperature superconductivity.

5. The method for preparing non-equimolar ratio high-performance high-entropy materials according to claim 4, characterized in that, In step S1, the Al-containing master alloy is AlV. 50 or AlCr 30 .

6. The method for preparing non-equimolar ratio high-performance high-entropy materials according to claim 4, characterized in that, In step S1, the metal blocks containing Al master alloy are 4-8 mm in size, and the metal blocks containing Nb, Ti, Cr and V are each 3-6 mm in size.

7. The method for preparing non-equimolar ratio high-performance high-entropy materials according to claim 4, characterized in that, In step S1, the conditions for vacuum arc melting are: a vacuum degree of 4 × 10⁻⁶. -3 ~5×10 -3 After evacuating the vacuum, fill with 0.3~0.5 atm of high-purity argon gas. The arc ignition current is 60~80A, the melting current is 110~140A, and the melting voltage is 20~25V. Note that the molten pool should be kept bright and stable with no obvious splashing.

8. The method for preparing non-equimolar ratio high-performance high-entropy materials according to claim 7, characterized in that, In step S1, the melting current for the first melting is 110~130A, the melting current for the second to sixth melting is 130~140A, and the melting current for the seventh to eighth melting is 110~120A.

9. The method for preparing non-equimolar ratio high-performance high-entropy materials according to claim 4, characterized in that, In step S2, the vacuum homogenization heat treatment is performed at a vacuum level of 5.0 × 10⁻⁶. -2 ~7.0×10 -3 Under a vacuum of Pa, the alloy is held at 1200~1300℃ for 12~16h, then furnace cooled to 400~500℃ and then air cooled to obtain a high-entropy alloy with high toughness and low-temperature superconductivity.

10. An application of the non-equimolar ratio high-performance high-entropy material according to any one of claims 1 to 4, characterized in that, Includes at least one or more of the following: 1) Quantum computing devices; 2) Aerospace cryogenic superconducting equipment; 3) Superconducting coils for medical magnetic resonance imaging equipment; 4) Superconducting magnet for nuclear fusion device.

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