Method for determining performance of actinide alloy material

Abstract

The embodiment of the invention relates to the field of testing or analyzing materials by means of measuring the chemical or physical properties of the materials, in particular to a method for determining the performance of an actinide element alloy material, which comprises the following steps of: determining the atomic structure and the electron density of the actinide element alloy material of which the performance is to be determined in a testing manner; determining a wave function according to the atomic structure and the electron density; according to the wave function, the interatomic stress of the actinide element alloy material is determined through an electronic smearing method; determining a high-order force constant according to the inter-atomic stress; determining a kinetic matrix of the actinide element alloy material according to the high-order force constant; determining a phonon spectrum of the actinide element alloy material according to the kinetic matrix; and determining the performance of the actinide element alloy material according to the phonon spectrum. According to the method provided by the embodiment of the invention, the performance of the actinide element alloy material at the conventional temperature and the high temperature can be determined, and data support can be provided for application of the actinide element alloy material in a fast reactor.

Description

Technical Field

[0001] Embodiments of the present application relate to the field of testing or analyzing materials by measuring the chemical or physical properties of the materials, and more particularly to a method for determining the properties of an actinide alloy material. Background Art

[0002] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0003] Actinide alloy materials are used as fuel cores in fast reactor metal fuel elements. The properties of actinide alloy materials will affect the irradiation behavior within the fuel pile and further affect the safety and economy of reactor operation. Therefore, it is necessary to determine the properties of actinide alloy materials in order to conduct research on the properties of actinide alloy materials.

[0004] Currently, the technology for determining the properties of actinide alloy materials still has many limitations. Summary of the Invention

[0005] A brief overview of the present application is provided below to provide a basic understanding of certain aspects of the present application. It should be understood that this overview is not an exhaustive overview of the present application. It is not intended to identify key or important portions of the present application, nor is it intended to limit the scope of the present application. Its purpose is simply to present certain concepts in a simplified form as a prelude to the more detailed description that will be discussed later.

[0006] In response to the above problems, an embodiment of the present application provides a method for determining the performance of an actinide alloy material, which includes the following steps: S10, determining the atomic structure and electron density of the actinide alloy material whose performance is to be determined by testing; S20, determining the wave function of the actinide alloy material based on the atomic structure and electron density; S30, determining the interatomic force of the actinide alloy material based on the wave function using an electron smearing method; S40, determining the high-order force constants of the actinide alloy material based on the interatomic force of the actinide alloy; S50, determining the kinetic matrix of the actinide alloy material based on the high-order force constants; S60, determining the phonon spectrum of the actinide alloy material based on the kinetic matrix; S70, determining the performance of the actinide alloy material based on the phonon spectrum.

[0007] The method provided in the embodiments of the present application determines the atomic structure and electron density of the actinide alloy material whose performance is to be determined by testing, so as to determine the performance of the actinide alloy material based on the atomic structure and electron density determined by the test, so that a relationship can be established between the performance of the determined actinide alloy material and the actual test data, which is beneficial to improving the reliability of the performance of the determined actinide alloy material; and by determining the wave function based on the atomic structure and electron density, determining the interatomic force based on the wave function, determining the high-order force constant based on the interatomic force, determining the dynamic matrix based on the high-order force constant, determining the phonon spectrum based on the dynamic matrix, and finally determining the performance of the actinide alloy material based on the phonon spectrum, the method provided in the embodiments of the present application is not limited by temperature when determining the performance of the actinide alloy material, so that not only the performance of the actinide alloy material at conventional temperature can be determined, but also the performance of the actinide alloy material at high temperature can be determined, which is beneficial to providing data support for the application of actinide alloy materials in fast reactors. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Other objects and advantages of the present application will become apparent from the following description of the embodiments of the present application with reference to the accompanying drawings, which will help to provide a comprehensive understanding of the present application.

[0009] Figure 1 It is a flowchart of the method provided in the embodiment of the present application.

[0010] Figure 2 It is a schematic diagram of the test resistivity of the actinide alloy material determined according to the method provided in the embodiment of the present application and the experimental resistivity of the actinide alloy material measured experimentally.

[0011] Figure 3 3 is a schematic diagram of a phonon spectrum determined using phonon spectrum data determined at 300K. The rectangular box in the figure represents the phonon spectrum data determined at 300K.

[0012] Figure 4 Schematic diagram of the phonon spectrum determined under smearing broadening of 0.05Ry.

[0013] Description of reference numerals:

[0014] 21. Test resistivity; 22. Experimental resistivity; 23. Phonon spectrum; 230. Phonon spectrum data.

[0015] It should be noted that the drawings are not necessarily drawn to scale, but are merely shown in a schematic manner that does not affect the reader's understanding. DETAILED DESCRIPTION

[0016] Exemplary embodiments of the present application will be described below with reference to the accompanying drawings. For the sake of clarity and conciseness, not all features of actual implementations are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the process of developing any such actual implementation in order to achieve the developer's specific goals, such as meeting those constraints related to the system and business, and these constraints may vary depending on the implementation. In addition, it should be understood that although the development work may be very complex and time-consuming, it is a routine task for those skilled in the art who benefit from the content of this application.

[0017] It is also necessary to explain here that, in order to avoid obscuring the present application due to unnecessary details, the accompanying drawings only show the device structure and / or processing steps that are closely related to the solution according to the present application, while other details that are not closely related to the present application are omitted.

[0018] In the related art, the performance of actinide alloy materials is typically determined at conventional temperatures. However, since anharmonic effects are more pronounced in actinide alloy materials at high temperatures, and are difficult to accurately determine in such environments, the methods used in the related art for determining the performance of actinide alloy materials cannot accurately determine the performance of actinide alloy materials in high-temperature environments where anharmonic effects exist. Since actinide alloy materials are exposed to high temperatures in fast reactors, determining the performance of actinide alloy materials in such environments remains an unresolved issue.

[0019] In view of the above problems, the embodiments of the present application provide a method for determining the properties of an actinide alloy material, see Figure 1 , Figure 1 : is a flow chart of a method provided in an embodiment of the present application, which may include the following steps: S10, determining the atomic structure and electron density of an actinide alloy material whose performance is to be determined by testing; S20, determining the wave function of the actinide alloy material based on the atomic structure and electron density; S30, determining the interatomic force of the actinide alloy material using an electron smearing method based on the wave function; S40, determining the high-order force constant of the actinide alloy material based on the interatomic force of the actinide alloy;

[0020] S50. Determine the kinetic matrix of the actinide alloy material based on the high-order force constants; S60. Determine the phonon spectrum of the actinide alloy material based on the kinetic matrix; S70. Determine the performance of the actinide alloy material based on the phonon spectrum.

[0021] The method provided in the embodiments of the present application determines the atomic structure and electron density of the actinide alloy material whose performance is to be determined by testing, so as to determine the performance of the actinide alloy material based on the atomic structure and electron density determined by the test, so that a relationship can be established between the performance of the determined actinide alloy material and the actual test data, which is beneficial to improving the reliability of the performance of the determined actinide alloy material; and by determining the wave function based on the atomic structure and electron density, determining the interatomic force based on the wave function, determining the high-order force constant based on the interatomic force, determining the dynamic matrix based on the high-order force constant, determining the phonon spectrum based on the dynamic matrix, and finally determining the performance of the actinide alloy material based on the phonon spectrum, the method provided in the embodiments of the present application is not limited by temperature when determining the performance of the actinide alloy material, so that not only the performance of the actinide alloy material at conventional temperature can be determined, but also the performance of the actinide alloy material at high temperature can be determined, which is beneficial to providing data support for the application of actinide alloy materials in fast reactors.

[0022] In some embodiments, the determined properties of the actinide alloy material may include thermal conductivity, electrical conductivity, resistivity, and mechanical properties of the actinide alloy material.

[0023] See also Figure 2 , Figure 2 2 is a schematic diagram of the test resistivity 21 of the actinide alloy material determined according to the method provided in the embodiment of the present application and the experimental resistivity 22 of the actinide alloy material measured experimentally, Figure 2 It can be seen that the error between the test resistivity 21 determined by the method provided in the embodiment of the present application and the experimental resistivity 22 measured experimentally is small, which shows that the method provided in the embodiment of the present application can accurately determine the performance of the actinide alloy material.

[0024] In some embodiments, step S30 may further include the following steps: S31, setting a smearing width of the actinide alloy material; S32, determining an equivalent electron entropy of the actinide alloy material based on the smearing width; and S33, determining the interatomic forces of the actinide alloy material based on the wave function and the electron entropy. In such an embodiment, by determining the equivalent electron entropy of the actinide alloy material and determining the interatomic forces of the actinide alloy material based on the wave function and the electron entropy, repeated determination of interatomic forces of different structural parameters can be reduced, thereby efficiently and quickly determining the interatomic forces of the actinide alloy material.

[0025] In some embodiments, step S32 may further include the following steps: S321, determining the electron occupation distribution function and energy of the actinide alloy material based on the smearing broadening; S322, determining the equivalent electron entropy of the actinide alloy material based on the electron occupation distribution function and energy. In such an embodiment, the above steps facilitate accurate and rapid determination of the equivalent electron entropy of the actinide alloy material, thereby facilitating accurate and rapid determination of the properties of the actinide alloy material.

[0026] In some embodiments, before step S70, the method may further include: repeating steps S30-S60 to determine different phonon spectra, so as to determine the performance of the actinide alloy material according to the different phonon spectra, thereby improving the accuracy and reliability of the determined performance of the actinide alloy material; and, by determining different phonon spectra, determining the performance of the actinide alloy material at different temperatures, thereby facilitating a comprehensive determination of the performance of the actinide alloy material.

[0027] In some embodiments, the set value of the smearing stretch is changed to determine different phonon spectra. In such embodiments, changing the set value of the smearing stretch can change the equivalent electron entropy of the actinide alloy material, thereby changing the interatomic forces, high-order force constants, and dynamic matrices of the actinide alloy material, thereby changing the phonon spectrum of the actinide alloy material. In the embodiments of the present application, by changing the set value of the smearing stretch, different phonon spectra can be determined, which can reduce the difficulty of determining different phonon spectra and help improve the efficiency of determining the properties of the actinide alloy material.

[0028] In some embodiments, step S70 may further include the following steps: S71, determining the phonon spectrum of the actinide alloy material at a predetermined temperature through experiments; S72, determining the smearing broadening of the actinide alloy material at the predetermined temperature based on the phonon spectrum determined in step S71; S73, repeating steps S71 to S72 to obtain multiple smearing broadenings corresponding to multiple predetermined temperatures; S74, determining the relationship between the smearing broadening and temperature; S75, determining the smearing broadening based on any temperature; S76, determining the phonon spectrum based on the smearing broadening. In the related art, a large number of experiments are required to determine the smearing broadening corresponding to any temperature in order to determine the phonon spectrum and the properties of the actinide alloy material, resulting in low efficiency in determining the properties of the actinide alloy material. In the embodiments of the present application, by determining multiple smearing broadenings corresponding to multiple predetermined temperatures to determine the relationship between the smearing broadening and temperature, the smearing broadening corresponding to any temperature can be determined based on the determined relationship between the smearing broadening and temperature, without the need for a large number of experiments, which is conducive to improving the efficiency of determining the properties of the actinide alloy material. The predetermined temperature may be 300K.

[0029] The relationship between the smear spread and the temperature is, for example, a polynomial relationship.

[0030] In some embodiments, in step S72, the following steps may be included: S721, determining the phonon spectrum of the actinide alloy material under multiple smearing broadenings; S722, comparing the phonon spectrum determined in step S71 with the phonon spectrum determined in step S721 to determine the smearing broadening of the actinide alloy material at a predetermined temperature.

[0031] In some embodiments, in step S721, before determining the phonon spectrum, the accuracy of the obtained phonon spectrum is determined so that the determined phonon spectrum can meet the preset accuracy. The preset accuracy is, for example, 10 -2 Ry.

[0032] Specifically, the process of determining the phonon spectrum of the actinide alloy material under multiple smearing broadenings is as follows.

[0033] (1) Test the k-grid density and cutoff energy under standard smearing broadening to ensure that the cutoff energy reaches a convergence value, and determine the band structure, state density, electron group velocity and Fermi surface of the actinide alloy material. The standard smearing broadening is, for example, 0.02Ry, and the convergence value of the cutoff energy is, for example, 10 -4 Ry.

[0034] (2) Using a preset calculation scheme to perform calculations within a preset widening range, determine the energy convergence of the actinide alloy material, and determine the calculation scheme that the energy convergence of the actinide alloy material reaches a preset value. The preset value of the energy convergence of the actinide alloy material is, for example, 10 -2 Ry, which can reflect the accuracy of the determined phonon spectrum.

[0035] (3) According to the calculation scheme determined in step (2), a phonon spectrum is calculated, and the phonon Q grid density in the calculated phonon spectrum is tested. Through the test, it is determined that the phonon Q grid in the calculated phonon spectrum is dense, thereby determining that the calculated phonon spectrum can reflect the performance of the actinide alloy material.

[0036] Specifically, see Figure 3 and Figure 4 , Figure 3 2 is a schematic diagram of a phonon spectrum 23 determined using the phonon spectrum data 230 determined at 300K. The rectangular box in the figure represents the phonon spectrum data 230 determined at 300K. Figure 4 is a schematic diagram of the phonon spectrum 23 determined under smearing broadening of 0.05Ry, Figure 3 and Figure 4It can be seen that the phonon spectrum 23 determined at 300 K is close to the phonon spectrum 23 determined at a smearing broadening of 0.05 Ry, so the phonon spectrum determined at 300 K corresponds to a smearing broadening of 0.05 Ry.

[0037] In some embodiments, the relationship between smear spread and temperature conforms to the following expression:

[0038] T=C0+C1σ+C2σ 2 , where T represents temperature, σ represents smear spread, and C0, C1, and C2 are constants determined by experiments. In such an embodiment, the relationship between smear spread and temperature can be accurately and quickly determined by the above relationship.

[0039] In some embodiments, the relationship between smear spread and temperature conforms to the following expression:

[0040] T=C0+C1σ+C2σ 2 +C3σ 3 , where T represents temperature, σ represents smear spread, and C0, C1, C2, and C3 are constants determined by experiments. In such an embodiment, the relationship between smear spread and temperature can be accurately and quickly determined by the above relationship.

[0041] In some embodiments, the relationship between smear spread and temperature conforms to the following expression:

[0042] T=C0+C1σ+C2σ 2 +C3σ 3 +C4σ 4 , where T represents temperature, σ represents smear spread, and C0, C1, C2, C3, and C4 are constants determined by experiments. In such an embodiment, the relationship between smear spread and temperature can be accurately and quickly determined by the above relationship.

[0043] In some embodiments, the relationship between smear spread and temperature conforms to the following expression:

[0044] T=C0+C1σ+C2σ 2 +C3σ 3 +C4σ 4 +C5σ 5 , where T represents temperature, σ represents smear spread, and C0, C1, C2, C3, C4, and C5 are constants determined by experiments. In such an embodiment, the relationship between smear spread and temperature can be accurately and quickly determined by the above relationship.

[0045] The method provided in the embodiments of the present application can select a suitable expression based on various relationships between smear broadening and temperature to accurately equate smear broadening to temperature, thereby facilitating the determination of the performance of actinide alloy materials at various temperatures.

[0046] In some embodiments, the performance of the actinide alloy material at a known temperature can be determined through experiments, and compared with the performance of the actinide alloy material at the known temperature determined by the method provided in the embodiments of the present application, so as to verify and improve the relationship between the determined smear broadening and temperature based on the comparison results, so as to improve the accuracy of the determined performance of the actinide alloy material.

[0047] In particular, the determined relationship between smearing broadening and temperature can be refined by determining the anharmonic effects of higher-order force constants.

[0048] Regarding the embodiments of the present application, it should also be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other to obtain new embodiments.

[0049] The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. The protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for determining the properties of an actinide alloy material, characterized in that: The steps include: S10. Determine the atomic structure and electron density of the actinide alloy material with the properties to be determined by testing; S20. Determining a wave function of the actinide alloy material according to the atomic structure and the electron density; S30. Determine the interatomic forces of the actinide alloy material using an electron smearing method according to the wave function; S40, determining a high-order force constant of the actinide alloy material according to the interatomic forces of the actinide alloy; S50, determining a kinetic matrix of the actinide alloy material according to the high-order force constants; S60, determining a phonon spectrum of the actinide alloy material according to the kinetic matrix; S70. Determine the properties of the actinide alloy material according to the phonon spectrum.

2. The determination method according to claim 1, characterized in that In step S30, the following steps are also included: S31, setting a smearing width of the actinide alloy material; S32. Determining the equivalent electronic entropy of the actinide alloy material according to the smear broadening; S33. Determine the interatomic force of the actinide alloy material according to the wave function and the electron entropy.

3. The determination method according to claim 2, characterized in that: In step S32, the following steps are also included: S321. Determine the electron occupation distribution function and energy of the actinide alloy material according to the smear broadening; S322. Determine the equivalent electron entropy of the actinide alloy material according to the electron occupation distribution function and energy.

4. The determination method according to claim 2, characterized in that: Before step S70, the following steps are also included: Repeat steps S30-S60 to determine different phonon spectra.

5. The determination method according to claim 4, characterized in that: Also includes: By changing the setting value of the smear broadening, different phonon spectra are determined.

6. The determination method according to claim 5, characterized in that: In step S70, the following steps are also included: S71. Determine the phonon spectrum of the actinide alloy material at a predetermined temperature through experiments; S72. Determine the smear broadening of the actinide alloy material at the predetermined temperature according to the phonon spectrum determined in step S71; S73, repeating steps S71 to S72 to obtain multiple smearing widths corresponding to multiple predetermined temperatures; S74, determining the relationship between the smearing spread and temperature; S75, determining the smearing widening according to an arbitrary temperature; S76. Determine the phonon spectrum according to the smearing and broadening.

7. The determination method according to claim 6, characterized in that: The relationship between the smearing broadening and the temperature conforms to the following expression: T=C0+C1σ+C2σ 2 , where T represents temperature, σ represents smearing broadening, and C0, C1, and C2 are constants determined experimentally.

8. The determination method according to claim 6, characterized in that: The relationship between the smearing broadening and the temperature conforms to the following expression: T=C0+C1σ+C2σ 2 +C3σ 3 , where T represents temperature, σ represents smearing broadening, and C0, C1, C2, and C3 are constants determined experimentally.

9. The determination method according to claim 6, characterized in that: The relationship between the smearing broadening and the temperature conforms to the following expression: T=C0+C1σ+C2σ 2 +C3σ 3 +C4σ 4 , where T represents temperature, σ represents smearing broadening, and C0, C1, C2, C3, and C4 are constants determined experimentally.

10. The determination method according to claim 6, characterized in that: The relationship between the smearing broadening and the temperature conforms to the following expression: T=C0+C1σ+C2σ 2 +C3σ 3 +C4σ 4 +C5σ 5 , where T represents temperature, σ represents smearing broadening, and C0, C1, C2, C3, C4, and C5 are constants determined experimentally.

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