A numerical simulation method for studying the properties of vacancies in equal molar ratio high entropy alloys

Abstract

The invention discloses a numerical simulation research method for vacancy properties of an equimolar ratio high entropy alloy, which relates to the technical field of numerical simulation of point defects of new materials, and comprises the following steps: 1) using FindIt software to search for the structure of each metal element in the equimolar ratio high entropy alloy to obtain lattice parameters; 2) using ATAT software to find the SQS supercell model of the equimolar ratio high entropy alloy; 3) using VASP software to optimize the SQS supercell structure; 4) constructing an equimolar ratio high entropy alloy vacancy model; 5) performing first principle calculation simulation on metal elements and crystal models containing vacancies, calculating the energy of metal elements and all equimolar ratio high entropy alloy crystal cells containing vacancies; 6) calculating the formation energy of all vacancies, and analyzing the formation characteristics of vacancies and the influencing factors on vacancy formation from different angles in the local environment. The formation mechanism and influencing factors of vacancies in equimolar ratio high entropy alloys are theoretically revealed.

Description

Technical Field

[0001] The invention relates to the technical field of numerical simulation of new material point defects, and in particular to a numerical simulation research method for vacancy properties of an equal molar ratio high entropy alloy. Background Art

[0002] With the increasing requirements for the fourth-generation reactors, the development of cladding materials that can meet the service requirements of the next-generation reactors has become one of the key issues in the development of nuclear energy. High-entropy alloys (HEAs) are expected to become candidate materials for the next-generation reactor cladding because of their comprehensive properties that are superior to traditional alloys, such as high strength, high hardness, high toughness, corrosion resistance, and radiation resistance.

[0003] Studies have shown that the excellent radiation resistance of HEA is due to the slow diffusion of atoms in the system. However, recent research results have shown that at the same temperature, CoCrFeMn 0.5 The diffusion coefficient of Ni is higher than that of conventional materials, which is contrary to the assumption of "slow diffusion". Since the macroscopic properties of HEA are the result of the formation and evolution of point defects, the generation of point defects is the first step and basis for the evolution of defects in irradiated materials. However, the microscopic mechanism of point defects is still unclear, especially vacancy defects. Therefore, it is very important to study which key factors affect the generation of vacancy defects and their impact on vacancy defects in HEA.

[0004] To date, most studies have focused on the evolution of the macroscopic properties of HEAs under irradiation, while there is a lack of relevant research on the initial stage of point defect formation, mainly because the complex local chemical environment brings great difficulties to experimental research, the construction of supercell structures and numerical analysis. Although positron annihilation spectroscopy is often used in experiments to study point defects in alloys, the various element types and complex local environments involved in HEAs will cause the defect formation energy to present a certain range rather than a single value. It is almost impossible to accurately measure the defect formation energy, so the defect behavior in HEAs cannot be studied simply by positron annihilation spectroscopy. In addition, studies have shown that AlNbTiZr refractory high-entropy alloys (RHEAs) have excellent properties such as high stability, oxidation resistance, high strength, good toughness, and low neutron cross section, making them candidates for cladding materials. Summary of the invention

[0005] Based on the problems existing in the background technology, the present application proposes a numerical simulation research method for the vacancy properties of equimolar high entropy alloys. Based on the first principles method of density functional theory, the atoms at each atomic site are deleted respectively, and the formation energy of all types of vacancies in the system is calculated. By analyzing the formation characteristics of vacancies and the factors affecting the formation of vacancies from different angles such as the types of atoms and the number of atoms in the local environment, the formation mechanism of vacancies in the equimolar high entropy alloy system is revealed from the atomic and molecular scale, providing a theoretical basis for the experimental preparation and research of the material.

[0006] The present invention is achieved through the following technical solutions:

[0007] A numerical simulation research method for vacancy properties of an equal molar ratio high entropy alloy is provided, comprising the following steps:

[0008] Step 1: Use FindIt software to search for the structure of each metal element in the high entropy alloy with equal molar ratio and obtain the lattice parameters of each metal element;

[0009] Step 2: Use ATAT software to find the SQS supercell model of the equimolar ratio high entropy alloy, and convert the obtained structure file into the VASP software file format;

[0010] Step 3: Optimize the obtained SQS supercell structure using VASP software to obtain the lattice parameters of the high entropy alloy with equal molar ratio;

[0011] Step 4: Construct an equal molar ratio high entropy alloy vacancy model;

[0012] Step 5: Perform first-principles calculation simulation on the metal element in the equal molar ratio high entropy alloy and the equal molar ratio high entropy alloy crystal model containing vacancies, and calculate the energy of the metal element in the equal molar ratio high entropy alloy and all the equal molar ratio high entropy alloy unit cells containing vacancies;

[0013] Step 6: Calculate the formation energy of all vacancies based on the energy calculated in step 5, and analyze the formation characteristics of vacancies and the factors affecting vacancy formation from different perspectives in the local environment.

[0014] Among them, the lattice parameters of the system simulated in step 3 are compared with the experimental results. The results obtained are consistent with the experiments, which confirms the accuracy of the SQS supercell model of the equimolar high entropy alloy obtained.

[0015] Among them, constructing a model containing vacancy defects in step 4 helps to reveal the structural characteristics of vacancy defects.

[0016] Among them, the results of calculating the energy of various systems and the formation energy of all types of vacancies described in steps 5 and 6, and analyzing the factors affecting the formation of vacancies from different angles, are used to determine the formation mechanism of vacancies in the SQS supercell of the equimolar high entropy alloy from a microscopic perspective.

[0017] This application calculates the formation energy of all vacancies in an equimolar high-entropy alloy system by a first-principles method based on density functional theory, and reveals the vacancy formation characteristics and influencing factors at the atomic and molecular levels by combining the atomic types and numbers in the local environment of the vacancies. This can provide a theoretical basis for the experimental preparation and research of the material, and has important scientific significance for the research on equimolar high-entropy alloys.

[0018] Furthermore, the method for constructing the vacancy model of the equimolar high entropy alloy in step 4 is: based on the SQS supercell model of the stable equimolar high entropy alloy obtained in step 2, a supercell structure containing vacancy defects is obtained by respectively deleting atoms at different positions in the supercell.

[0019] Furthermore, the method for performing first-principles calculation and simulation on the metal elements in the equimolar high-entropy alloy and the equimolar high-entropy alloy crystal model containing vacancies in step 5 is: optimizing the supercell structure to obtain the structure corresponding to the lowest energy, and calculating the energy of the equimolar high-entropy alloy metal elements and all equimolar high-entropy alloy unit cells containing vacancies by a first-principles calculation method based on density functional theory.

[0020] Furthermore, the specific method for calculating the energy of the equimolar ratio high entropy alloy metal element and all vacancy-containing equimolar ratio high entropy alloy unit cells using the first principle calculation method based on density functional theory is:

[0021] The VASP software package based on the plane wave method was used for energy calculation. During the calculation, the PAW pseudopotential and PBE-form GGA were used to approximate the electronic structure and exchange-correlation interaction.

[0022] Furthermore, the specific method for obtaining the SQS supercell model of the equal molar ratio high entropy alloy using ATAT software in step 2 is:

[0023] Under the Linux system, generate a folder containing a lat.in file. The lat.in file contains three parts: lattice constant, basis vector, and atomic position. Change the metal element composition in the lat.in file to 25% for submission, and convert the final structure file into the VASP software file format.

[0024] Furthermore, the formula for calculating the formation energy of all vacancies in step 6 is:

[0025]

[0026] in, is the vacancy formation energy;

[0027] E Vac and E perfect are the energies of the system containing vacancies and the perfect unit cell, respectively;

[0028] μ i is the chemical potential of the defect i (i represents the metal atom in the high entropy alloy with equal molar ratio).

[0029] Furthermore, in step 6, based on the obtained formation energy, the specific method for analyzing the formation characteristics of vacancies and the factors affecting the formation of vacancies from different perspectives in the local environment is:

[0030] Construct a distribution map of the formation energies of different types of vacancies;

[0031] Construct a trend chart of the number of atoms of different elements that are the first nearest neighbors of the vacancy formation energy vacancy;

[0032] Construct a trend graph of the formation energy of different types of vacancies as a function of the number of atoms of different elements that are the first nearest neighbors of the vacancy.

[0033] Furthermore, the different angles include atomic types and atomic numbers.

[0034] Furthermore, the equimolar ratio high entropy alloy includes AlNbTiZr alloy.

[0035] In addition to the AlNbTiZr alloy exemplified by the above method, other high entropy alloys with equal molar ratios are also applicable.

[0036] Furthermore, when calculating the energy of the metal element of AlNbTiZr alloy and all high entropy alloy unit cells with equal molar ratios containing vacancies, in the metal element, the plane wave cutoff energy is 450 eV, the k-point is 3×3×3, the electron convergence accuracy is 1E-4, and the ion accuracy is 5E-2, and the energy of the stable structure of Al, Nb, Ti and Zr metal elements is obtained;

[0037] In the AlNbTiZr high entropy alloy unit cell containing vacancies, the plane wave cutoff energy is 350eV, the k-point is 2×2×2, the electron convergence accuracy is 1E-4, and the ion accuracy is 5E-2. The energy of all AlNbTiZr high entropy alloy unit cell systems containing vacancies is obtained.

[0038] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0039] (1) The present invention provides a method for studying the properties of vacancies in SQS supercells of equimolar high entropy alloys using a first-principles calculation method based on density functional theory, revealing the vacancy formation mechanism in the material from the atomic and molecular scales;

[0040] (2) The present invention belongs to a numerical simulation research method. It can predict the vacancy formation energy only through atomic coordinates and potential files, and analyze the microscopic mechanism affecting vacancy formation, which can provide a theoretical basis for experimental preparation and research of materials and has important scientific significance for the research of equimolar high entropy alloys.

[0041] (3) The numerical simulation research method provided by the present invention overcomes the shortcomings of experimental research on material irradiation in nuclear reactors, such as long cycle and high cost, and difficulty in revealing the behavior of point defects in the early stage of irradiation at the atomic scale. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0043] Figure 1 Schematic diagram of a flow chart of a method for numerical simulation of vacancy properties of an equimolar ratio AlNbTiZr high entropy alloy in Example 2 of the present invention;

[0044] Figure 2 Schematic diagram of the SQS structure of the medium molar ratio AlNbTiZr high entropy alloy in Example 2 of the present invention;

[0045] Figure 3 is a distribution diagram of the formation energy of different types of vacancies in Example 2 of the present invention;

[0046] Figure 4 A graph showing the variation trend of the vacancy formation energy with the number of atoms of different elements that are the first nearest neighbors of the vacancy in Example 2 of the present invention;

[0047] Figure 5 This is a graph showing the variation trend of the vacancy formation energy of the same type in the middle of Example 2 of the present invention as the number of atoms of different elements as the first nearest neighbors of the vacancy changes. DETAILED DESCRIPTION

[0048] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0049] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] The terms "comprises," "comprising," or any other variation thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0051] Example 1

[0052] This embodiment provides a numerical simulation research method for vacancy properties of high entropy alloys with equal molar ratio, comprising the following steps:

[0053] Step 1: Use FindIt software to search for the structure of each metal element in the high entropy alloy with equal molar ratio and obtain the lattice parameters of each metal element;

[0054] Step 2: Use ATAT software to find the SQS supercell model of the equimolar ratio high entropy alloy, and convert the obtained structure file into the VASP software file format;

[0055] Step 3: Optimize the obtained SQS supercell structure using VASP software to obtain the lattice parameters of the high entropy alloy with equal molar ratio;

[0056] Step 4: Construct an equal molar ratio high entropy alloy vacancy model;

[0057] Step 5: Perform first-principles calculation simulation on the metal element in the equal molar ratio high entropy alloy and the equal molar ratio high entropy alloy crystal model containing vacancies, and calculate the energy of the metal element in the equal molar ratio high entropy alloy and all the equal molar ratio high entropy alloy unit cells containing vacancies;

[0058] Step 6: Calculate the formation energy of all vacancies based on the energy calculated in step 5, and analyze the formation characteristics of vacancies and the factors affecting vacancy formation from different perspectives in the local environment.

[0059] Among them, the lattice parameters of the system simulated in step 3 are compared with the experimental results. The results obtained are consistent with the experiments, which confirms the accuracy of the SQS supercell model of the equimolar high entropy alloy obtained.

[0060] Among them, constructing a model containing vacancy defects in step 4 helps to reveal the structural characteristics of vacancy defects.

[0061] Among them, the results of calculating the energy of various systems and the formation energy of all types of vacancies described in steps 5 and 6, and analyzing the factors affecting the formation of vacancies from different angles, are used to determine the formation mechanism of vacancies in the SQS supercell of the equimolar high entropy alloy from a microscopic perspective.

[0062] This application calculates the formation energy of all vacancies in an equimolar high-entropy alloy system by a first-principles method based on density functional theory, and reveals the vacancy formation characteristics and influencing factors at the atomic and molecular levels by combining the atomic types and numbers in the local environment of the vacancies. This can provide a theoretical basis for the experimental preparation and research of the material, and has important scientific significance for the research on equimolar high-entropy alloys.

[0063] Specifically, the method for constructing the vacancy model of the equimolar high entropy alloy in step 4 is: based on the SQS supercell model of the stable equimolar high entropy alloy obtained in step 2, a supercell structure containing vacancy defects is obtained by respectively deleting atoms at different positions in the supercell.

[0064] Specifically, the method for performing first-principles calculation and simulation on the metal elements in the equimolar high-entropy alloy and the equimolar high-entropy alloy crystal model containing vacancies in step 5 is: optimizing the supercell structure to obtain the structure corresponding to the lowest energy, and calculating the energy of the equimolar high-entropy alloy metal elements and all equimolar high-entropy alloy unit cells containing vacancies by a first-principles calculation method based on density functional theory.

[0065] Specifically, the specific method for calculating the energy of an equimolar ratio high entropy alloy metal element and all vacancy-containing equimolar ratio high entropy alloy unit cells is as follows:

[0066] The VASP software package based on the plane wave method was used for energy calculation. During the calculation, the PAW pseudopotential and PBE-form GGA were used to approximate the electronic structure and exchange-correlation interaction.

[0067] Specifically, the specific method for obtaining the SQS supercell model of the equal molar ratio high entropy alloy using ATAT software in step 2 is:

[0068] Under the Linux system, generate a folder containing a lat.in file. The lat.in file contains three parts: lattice constant, basis vector, and atomic position. Change the metal element composition in the lat.in file to 25% for submission, and convert the final structure file into the VASP software file format.

[0069] Specifically, the formula for calculating the formation energy of all vacancies in step 6 is:

[0070]

[0071] in, is the vacancy formation energy;

[0072] E Vac and E perfect are the energies of the system containing vacancies and the perfect unit cell, respectively;

[0073] μ i is the chemical potential of the defect i (i represents the metal atom in the high entropy alloy with equal molar ratio).

[0074] Specifically, in step 6, based on the obtained formation energy, the specific method for analyzing the formation characteristics of vacancies and the factors affecting the formation of vacancies from different perspectives in the local environment is:

[0075] Construct a distribution map of the formation energies of different types of vacancies;

[0076] Construct a trend chart of the number of atoms of different elements that are the first nearest neighbors of the vacancy formation energy vacancy;

[0077] Construct a trend graph of the formation energy of different types of vacancies as a function of the number of atoms of different elements that are the first nearest neighbors of the vacancy.

[0078] Specifically, different angles include atomic types and atomic numbers.

[0079] Example 2

[0080] like Figure 1 As shown, this embodiment provides a numerical simulation research method for vacancy properties of equal molar ratio high entropy alloys, specifically a numerical simulation research method for vacancy properties of equal molar ratio AlNbTiZr HEA. The operation steps are as follows:

[0081] S101: Use FindIt software to search for the structures of Al, Nb, Ti, and Zr metal elements, and obtain the structures of the lattice parameters of Al, Nb, Ti, and Zr metal elements as follows:

[0082] Al: α=β=γ=90°;

[0083] Nb: α=β=γ=90°;

[0084] Ti: α=β=90°,γ=120°;

[0085] Zr: α=β=90°,γ=120°;

[0086] S102: Use ATAT software to find the SQS supercell model of the AlNbTiZr high entropy alloy with equal molar ratio. The model size is 4×4×4, containing 128 atoms, and the obtained structure file is converted into the VASP software file format through relevant commands. Specifically: Under the Linux system, generate a folder containing a lat.in file. The lat.in file contains three parts: lattice constant, basis vector, and atomic position. Change the Al, Nb, Ti, and Zr atomic compositions in the lat.in file to 25% for submission, and convert the final structure file into the VASP software file format.

[0087] S103: The obtained SQS supercell structure is optimized using VASP software, and the lattice parameters of the equimolar AlNbTiZr high entropy alloy are obtained as follows: α=β=γ=90°, and the obtained structure is consistent with the experimental structure;

[0088] The lattice parameters of the equimolar ratio AlNbTiZr high entropy alloy found in the literature are (The literature is W.Chen, Q.Tang, H.Wang, Y.Xie, X.Yan, P.Dai, Microstructure and mechanical properties of anovel refractory AlNbTiZr high-entropy alloy, Materials Science and Technology34(11)(2018)1309-1315.);

[0089] Among them, a, b, and c are the lattice parameters of the three directions of the unit cell, and α, β, and γ are the angles between the three directions of the unit cell;

[0090] The SQS supercell model of 4×4×4 equimolar ratio AlNbTiZr high entropy alloy is obtained as follows Figure 2 As shown, the structure contains lattice parameters and atomic positions;

[0091] Among them, 4×4×4 represents 4a×4b×4c.

[0092] S104: Construct a vacancy model of an equimolar AlNbTiZr high entropy alloy. Based on the SQS supercell model of a stable equimolar AlNbTiZr high entropy alloy obtained in S103, a supercell structure containing vacancy defects is obtained by deleting atoms at different positions in the supercell.

[0093] S105: Perform first-principles calculations and simulations on Al, Nb, Ti and Zr metal elements and AlNbTiZr high entropy alloy crystal models containing vacancies: optimize the supercell structure to obtain the structure corresponding to the lowest energy; calculate the energy of Al, Nb, Ti and Zr metal elements and all AlNbTiZr high entropy alloy crystal cells containing vacancies by first-principles calculation methods based on density functional theory;

[0094] The specific process of calculating the energy of Al, Nb, Ti and Zr metal elements and all AlNbTiZr high entropy alloy unit cells containing vacancies using the first-principles calculation method based on density functional theory is as follows:

[0095] The VASP software package based on the plane wave method is used for energy calculation. During the calculation process, the PAW pseudopotential and the PBE form of GGA are used to approximate the electronic structure and exchange-correlation interaction.

[0096] Among them, in the metal element, the plane wave cutoff energy is 450eV, the k point is 3×3×3, the electron convergence accuracy is 1E-4, and the ion accuracy is 5E-2, and the energy of the stable structure of Al, Nb, Ti and Zr metal elements is obtained;

[0097] In the AlNbTiZr high entropy alloy unit cell containing vacancies, the plane wave cutoff energy is 350eV, the k-point is 2×2×2, the electron convergence accuracy is 1E-4, and the ion accuracy is 5E-2. The energy of all AlNbTiZr high entropy alloy unit cell systems containing vacancies is obtained.

[0098] S106: Calculate the formation energy of all vacancies based on the system energies obtained in S105, and analyze the formation characteristics of vacancies and the factors affecting vacancy formation from different perspectives such as the types of atoms and the number of atoms in the local environment;

[0099] The formula for calculating the formation energy of all vacancies is:

[0100]

[0101] in, is the vacancy formation energy;

[0102] E Vac and E perfect are the energies of the system containing vacancies and the perfect unit cell, respectively;

[0103] μ i is the chemical potential of the defect i (i represents the metal atom in the high entropy alloy with equal molar ratio).

[0104] Based on the obtained formation energy, the formation characteristics of vacancies and the factors affecting vacancy formation are analyzed from different perspectives such as the types of atoms and the number of atoms in the local environment:

[0105] Construct a distribution map of the formation energy of different types of vacancies, such as Figure 3 As shown, the formation difficulty of vacancies of various elements can be obtained in this way;

[0106] Construct a trend graph of the vacancy formation energy as a function of the number of atoms of different elements that are the first nearest neighbors of the vacancy, such as Figure 4 As shown, this analysis method can be used to obtain the effects of different elements on vacancy formation;

[0107] Construct a trend graph of the formation energy of different types of vacancies as a function of the number of atoms of different elements in the first nearest neighbor of the vacancy, such as Figure 5 As shown, this analysis method can be used to obtain the influence of characteristic elements on the formation of specific types of vacancies.

[0108] A numerical simulation research method for vacancies in an equimolar AlNbTiZr high entropy alloy is proposed in this embodiment. The formation energy of all vacancies in the equimolar AlNbTiZr high entropy alloy system, the atomic types and number of atoms in the local environment of the structural vacancies are calculated by a first-principles method based on density functional theory, and the vacancy formation characteristics and influencing factors are revealed at the atomic and molecular levels. This can provide a theoretical basis for the experimental preparation and research of the material, and has important scientific significance for the research on the equimolar AlNbTiZr high entropy alloy.

[0109] The specific embodiments described above further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only the specific embodiments of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention. For those skilled in the art, it is obvious that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or basic features of the present application. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present application is limited by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims in the present application.

Claims

1. A numerical simulation research method for vacancy properties of equimolar high entropy alloys, characterized in that: The following steps are involved: Step 1: Use FindIt software to search for the structure of each metal element in the high entropy alloy with equal molar ratio and obtain the lattice parameters of each metal element; Step 2: Use ATAT software to find the SQS supercell model of the equimolar ratio high entropy alloy, and convert the obtained structure file into the VASP software file format; Step 3: Optimize the obtained SQS supercell structure using VASP software to obtain the lattice parameters of the high entropy alloy with equal molar ratio; Step 4: Construct an equal molar ratio high entropy alloy vacancy model; Step 5: Perform first-principles calculation simulation on the metal element in the equal molar ratio high entropy alloy and the equal molar ratio high entropy alloy crystal model containing vacancies, and calculate the energy of the metal element in the equal molar ratio high entropy alloy and all the equal molar ratio high entropy alloy unit cells containing vacancies; Step 6: Calculate the formation energy of all vacancies based on the energy calculated in step 5, and analyze the formation characteristics of vacancies and the factors affecting vacancy formation from different perspectives in the local environment; The method for constructing the vacancy model of the equimolar ratio high entropy alloy in step 4 is: based on the SQS supercell model of the stable equimolar ratio high entropy alloy obtained in step 2, a supercell structure containing vacancy defects is obtained by respectively deleting atoms at different positions in the supercell; The formula for calculating the formation energy of all vacancies in step 6 is: in, is the vacancy formation energy; E Vac and E perfect are the energies of the system containing vacancies and the perfect unit cell, respectively; μ i is the chemical potential of defect i atom, i represents the metal atom in the high entropy alloy with equal molar ratio; In step 6, based on the obtained formation energy, the specific method for analyzing the formation characteristics of vacancies and the factors affecting the formation of vacancies from different perspectives in the local environment is as follows: Construct a distribution map of the formation energies of different types of vacancies; Construct a trend chart of the number of atoms of different elements that are the first nearest neighbors of the vacancy formation energy vacancy; Construct a trend graph of the formation energy of different types of vacancies as a function of the number of atoms of different elements as the first nearest neighbors of the vacancy.

2. The method for numerical simulation of vacancy properties of high entropy alloys with equal molar ratio according to claim 1, characterized in that: The method for performing first-principles calculation simulation on the metal elements in the equimolar high-entropy alloy and the equimolar high-entropy alloy crystal model containing vacancies in step 5 is: optimizing the supercell structure to obtain the structure corresponding to the lowest energy, and calculating the energy of the equimolar high-entropy alloy metal elements and all equimolar high-entropy alloy unit cells containing vacancies by a first-principles calculation method based on density functional theory.

3. The method for numerical simulation of vacancy properties of high entropy alloys with equal molar ratio according to claim 2, characterized in that: The specific method of calculating the energy of the equimolar ratio high entropy alloy metal element and all vacancy-containing equimolar ratio high entropy alloy unit cells by the first principle calculation method based on density functional theory is: The energy calculation was performed using the VASP software package based on the plane wave method. During the calculation, the PAW pseudopotential and the PBE form of GGA were used to approximate the electronic structure and exchange-correlation interaction.

4. The method for numerical simulation of vacancy properties of high entropy alloys with equal molar ratio according to claim 1, characterized in that: The specific method of obtaining the SQS supercell model of the equal molar ratio high entropy alloy using ATAT software in step 2 is: Under the Linux system, generate a folder containing a lat.in file. The lat.in file contains three parts: lattice constant, basis vector, and atomic position. Change the metal element composition in the lat.in file to 25% for submission, and convert the final structure file into the VASP software file format.

5. The numerical simulation research method for vacancy properties of high entropy alloys with equal molar ratio according to claim 1, characterized in that: The different angles include atomic types and atomic numbers.

6. A numerical simulation research method for vacancy properties of high entropy alloys with equal molar ratio according to any one of claims 1 to 5, characterized in that: The equimolar ratio high entropy alloy includes AlNbTiZr alloy.

7. The method for numerical simulation of vacancy properties of high entropy alloys with equal molar ratio according to claim 6, characterized in that: When calculating the energy of the metal element of AlNbTiZr alloy and all high entropy alloy unit cells with equal molar ratios containing vacancies, in the metal element, the plane wave cutoff energy is 450eV, the k point is 3×3×3, the electron convergence accuracy is 1E-4, and the ion accuracy is 5E-2, and the energy of the stable structure of Al, Nb, Ti and Zr metal elements is obtained; In the AlNbTiZr high entropy alloy unit cell containing vacancies, the plane wave cutoff energy is 350eV, the k-point is 2×2×2, the electron convergence accuracy is 1E-4, and the ion accuracy is 5E-2. The energy of all AlNbTiZr high entropy alloy unit cell systems containing vacancies is obtained.

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