Quantitative calculation method and system for local lattice distortion of high-entropy alloy and medium

Abstract

The invention relates to a high-entropy alloy local lattice distortion quantitative calculation method and system and a medium, the high-entropy alloy local lattice distortion quantitative calculation method comprises the following steps: S1; collecting an X-ray diffraction spectrogram of the high-entropy alloy; s2, analyzing and determining the crystal structure of the high-entropy alloy according to the X-ray diffraction spectrogram; s3, calculating to obtain a lattice constant according to the lattice structure through full-spectrum fitting of the X-ray diffraction spectrogram; s4, according to the geometrical relationship between the lattice constant and the crystal structure, calculating to obtain an average atom pair spacing; s5, fine structure spectrums absorbed by X rays of different alloy elements K-edge or L-edge in the high-entropy alloy are collected; s6, analyzing and determining the average atom pair spacing of the specific element and the nearest neighbor element; and S7, the local lattice distortion amount and the average lattice distortion amount of specific element atoms of the high-entropy alloy are obtained through calculation. According to the method, the quantitative calculation of the local lattice distortion of the high-entropy alloy with the element recognition capability is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of metal material microstructure design, and in particular to a quantitative calculation method, system and medium for local lattice distortion of high entropy alloys. Background Art

[0002] High entropy alloy is a new type of high-performance single solid solution alloy that breaks through the traditional alloy design concept. It has excellent mechanical properties such as high strength, high hardness, high plasticity, resistance to high temperature softening, radiation resistance, and wear resistance. It is considered to be the new type of high-performance metal structural material with the most application potential in major key areas such as national economy and national security. The unique atomic-scale structural characteristics of high-entropy alloys are closely related to their deformation mechanism, but there is still a lack of in-depth understanding. Elucidating the atomic-scale structural characteristics of high-entropy alloys is very important for the composition design and structural regulation of new high-performance high-entropy alloys.

[0003] Lattice distortion is considered to be one of the unique atomic-scale structural features of high-entropy alloys that distinguishes them from traditional alloys, and is also one of the four core effects of high-entropy alloys. However, there are certain differences between the experimental research results and theoretical calculation results on the degree of lattice distortion of high-entropy alloys, and it is inconsistent with the severe lattice distortion proposed in previous studies. However, the current understanding of this difference is not very clear, and there is even some controversy. For this reason, in-depth research and understanding of the lattice distortion of high-entropy alloys has become an important scientific issue that cannot be avoided in the research and development of high-entropy alloys and the regulation of the microscopic mechanism of mechanical properties. It has important scientific significance and application value for the composition design of new high-performance high-entropy alloys and the local structure regulation of mechanical properties.

[0004] There are certain differences in the atomic sizes of various components in the high entropy alloy system, and deviations are inevitable when occupying the ideal lattice site. According to the atomic close-packing hypothesis, some atoms may be "oppressed" and other atoms may be "pulled", causing a certain degree of lattice distortion. This distortion is not only related to the size of the element atoms, but also closely related to their electronegativity. In conventional theoretical calculations, the element atoms are assumed to be hard sphere models, and the atomic radius of metal atoms in the alloy is considered to be fixed. The degree of lattice distortion of high entropy alloys is calculated based on this assumption. However, once metal atoms participate in the alloying process in the alloy, certain interactions will inevitably occur between different atoms and between the same atoms. Due to the difference in electronegativity, the atomic radius of metal atoms will also change accordingly during the alloying process, which makes the calculation results based on the hard sphere model assumption often too large. How to avoid the difficulties caused by the atomic radius of metal element atoms after alloying is an urgent problem to be solved. Summary of the invention

[0005] The present invention provides a method, system and medium for quantitatively calculating local lattice distortion of high entropy alloys.

[0006] To achieve the above objectives, in a first aspect, the present invention provides a method for quantitatively calculating local lattice distortion of a high entropy alloy, comprising:

[0007] S1; collect X-ray diffraction spectra of high entropy alloys;

[0008] S2: Analyze and determine the crystal structure of the high entropy alloy according to the X-ray diffraction spectrum;

[0009] S3: Calculating the lattice constant according to the lattice structure by full spectrum fitting of the X-ray diffraction spectrum;

[0010] S4: calculating an average atomic pair distance according to the geometric relationship between the lattice constant and the crystal structure;

[0011] S5: Collect the fine structure spectra of X-ray absorption of K-edge or L-edge of different alloying elements in high entropy alloys;

[0012] S6: analyzing and determining the average atomic pair distance between the specific element and its nearest neighbor element through the fine structure spectrum of the specific element;

[0013] S7: Substituting the obtained average atomic pair spacing parameter into a preset local lattice distortion formula, the local lattice distortion amount and the average lattice distortion amount of the specific element atoms in the high entropy alloy are calculated.

[0014] Preferably, the local lattice distortion formula is as follows:

[0015]

[0016] Among them, χ i represents the local lattice distortion of the specific element i, C j represents the atomic percentage of the specific element i in the alloy material, r i-j represents the average atomic pair distance of the nearest neighbor atom j centered on the specific element i, Represents the average distance between atomic pairs in alloy materials.

[0017] To achieve the above-mentioned object, in a second aspect, the present invention also relates to a quantitative calculation system for local lattice distortion of a high entropy alloy, comprising: a diffraction spectrum collection module, for collecting an X-ray diffraction spectrum of the high entropy alloy;

[0018] A crystal structure determination module, used to analyze and determine the crystal structure of the high entropy alloy according to the X-ray diffraction spectrum;

[0019] A lattice constant calculation module, used to calculate the lattice constant according to the lattice structure by full spectrum fitting of the X-ray diffraction spectrum;

[0020] An average atomic pair spacing calculation module, used to calculate the average atomic pair spacing according to the geometric relationship between the lattice constant and the crystal structure;

[0021] Fine structure spectrum collection module, used to collect the fine structure spectrum of X-ray absorption of K-edge or L-edge of different alloy elements in high entropy alloys;

[0022] A neighboring average atomic pair spacing calculation module is used to analyze and determine the average atomic pair spacing between the specific element and its nearest neighbor element through the fine structure spectrum of the specific element;

[0023] The lattice distortion calculation module is used to substitute the obtained average atomic pair spacing parameter into a preset local lattice distortion formula to calculate the local lattice distortion and average lattice distortion of the specific element atoms in the high entropy alloy.

[0024] To achieve the above-mentioned purpose, in a third aspect, the present invention also relates to a computer-readable storage medium, in which instructions are stored, and when the instructions are run, the above-mentioned method for quantitatively calculating the local lattice distortion of a high-entropy alloy is executed.

[0025] The present invention relates to a method, system and medium for quantitatively calculating local lattice distortion of high entropy alloys, which have the following beneficial effects compared with the prior art:

[0026] The present invention combines the crystal structure, X-ray diffraction spectrum and X-ray absorption fine structure spectrum of the alloy material to realize the quantitative calculation of the local lattice distortion of the high-entropy alloy with element identification ability, providing key experimental data support for the design and development of new high-performance high-entropy alloys.

[0027] In order to avoid the difficulties caused by the atomic radius of metal element atoms after alloying, a new parameter is cleverly introduced in the present invention: the spacing between the nearest neighbor atoms, and the local lattice distortion of the atoms of a specific element is calculated based on the deviation between the spacing between the nearest neighbor atomic pairs of the atoms of the specific element and the average atomic spacing. The local lattice distortion of the atoms of the alloying element is calculated by replacing the atomic radius with the average atomic pair spacing and the nearest neighbor atomic pair spacing. The average atomic pair spacing of the atoms of the alloying element is obtained by using the X-ray diffraction spectrum, and the nearest neighbor atomic pair spacing of the atoms of the element is obtained by using the X-ray absorption fine structure spectrum. This method not only avoids the difficult measurement and multi-variable problems of the real atomic radius, but also uses the experimental parameter nearest neighbor atomic pair spacing that can be measured in the experiment, which is highly operable and closer to the actual distortion situation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a method flow chart of a method for quantitatively calculating local lattice distortion of a high entropy alloy in Embodiment 1 of the present invention;

[0029] Figure 2 A schematic diagram of the FCC crystal structure of a method for quantitatively calculating local lattice distortion of a high entropy alloy in Example 1 of the present invention;

[0030] Figure 3 The XRD spectrum of the CrMnFeCoNi high entropy alloy with FCC structure and the full spectrum fitting result thereof of a quantitative calculation method for local lattice distortion of a high entropy alloy in Example 1 of the present invention;

[0031] Figure 4 It is an XAFS spectrum of a CrMnFeCoNi high entropy alloy with an FCC structure and a full spectrum fitting result thereof according to a method for quantitatively calculating local lattice distortion of a high entropy alloy in Example 1 of the present invention;

[0032] Figure 5 It is a schematic diagram of the local lattice distortion of the CrMnFeCoNi high entropy alloy with FCC structure according to a quantitative calculation method of the local lattice distortion of the high entropy alloy in the first embodiment of the present invention;

[0033] Figure 6 The local lattice distortion results of different alloying elements in the CrMnFeCoNi high entropy alloy obtained by calculation in a method for quantitatively calculating the local lattice distortion of a high entropy alloy in Example 1 of the present invention;

[0034] Figure 7 It is a structural schematic diagram of a system for quantitatively calculating local lattice distortion of a high entropy alloy in Embodiment 2 of the present invention. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0036] Embodiment 1

[0037] A quantitative calculation method for local lattice distortion in high entropy alloys, see Figure 1-Figure 6 , used for, comprising the following steps: S1 to S7.

[0038] S1; Collect X-ray diffraction spectra of high entropy alloys.

[0039] In this embodiment, step S1 is specifically as follows: relying on the diffraction experimental station of the synchrotron radiation device to collect the X-ray diffraction spectrum of the CrMnFeCoNi high entropy alloy, the 2θ angle range is 30-100°, and the step size is set to 0.02°.

[0040] S2: Analyze and determine the crystal structure of the high entropy alloy based on the X-ray diffraction spectrum.

[0041] In this embodiment, step S2 is specifically: performing phase analysis on the collected X-ray diffraction spectrum through Highscore software to determine the crystal structure of the high entropy alloy, and the crystal structure of the CrMnFeCoNi high entropy alloy is a face-faced cubic structure FCC. Common crystal structures of high entropy alloys are face-faced cubic structure (FCC), body-centered cubic structure (BCC) and hexagonal close-packed structure (HCP).

[0042] S3: The lattice constant is calculated based on the lattice structure by fitting the entire X-ray diffraction spectrum.

[0043] Specifically, professional X-ray diffraction spectrum data analysis software is used to perform full spectrum fitting on the X-ray diffraction spectrum of the alloy material using appropriate functions according to the crystal structure of the alloy material, so as to obtain the lattice constant.

[0044] In this embodiment, step S3 specifically includes: using Highscore software to perform full spectrum fitting on the obtained X-ray diffraction spectrum to obtain the lattice constant of the CrMnFeCoNi high entropy alloy.

[0045] S4: Based on the geometric relationship between the lattice constant and the crystal structure, the average atomic pair spacing is calculated.

[0046] According to the crystal structure of the alloy material, there is a specific geometric relationship between the lattice constant and the average atomic pair spacing. Taking the oriented cubic structure FCC as an example, the average atomic pair spacing and the lattice constant have the following relationship: According to the geometric relationship between the lattice constant and crystal structure of the oriented cubic structure FCC The average atomic pair distance is calculated, a is the lattice constant, Average atomic pair distance.

[0047] S5: Collect the fine structure spectra of X-ray absorption of K-edge or L-edge of different alloying elements in high entropy alloys.

[0048] When the X-ray energy is equal to the ionization energy of an inner electron of the irradiated sample, resonant absorption occurs, ionizing the electron into a photoelectron, and the X-ray absorption coefficient undergoes a sudden change. This sudden change is called an absorption edge. The absorption edges of electrons with different principal quantum numbers in atoms are quite far apart, and are named K, L absorption edges, etc. according to the principal quantum number. The photoelectrons generated by the X-ray excitation are scattered by the surrounding coordinated atoms, causing the X-ray absorption intensity to oscillate with energy. Because this oscillation is related to the electronic and geometric structure of the material, it is called the fine structure of the X-ray absorption spectrum (XAFS X-ray Absorption Fine Structure).

[0049] S5 is specifically: relying on synchrotron radiation X-ray absorption spectrometer or laboratory X-ray absorption spectrometer, according to the type of alloy material, select the appropriate energy absorption edge, such as transition metal Cu generally selects K edge, and precious metal Pt generally selects L edge, to obtain high-quality X-ray absorption fine structure spectrum XAFS spectral lines.

[0050] In this embodiment, relying on the synchrotron radiation X-ray absorption fine structure spectrum experimental station, the fine structure spectra of X-ray absorption of K-edge of Cr, Mn, Fe, Co and Ni elements are collected respectively, and the energy range is -200eV before the absorption edge to 1000eV after the absorption edge.

[0051] S6: Analyze and determine the average atomic pair distance between a specific element and its nearest neighbor elements through the fine structure spectrum of the specific element.

[0052] Specifically, professional XAFS spectrum analysis software is used to obtain the average atomic pair distance between element i and its nearest neighbor element j through fitting.

[0053] In this embodiment, S6 specifically comprises: using the X-ray absorption fine structure spectrum analysis software Athena and Artemis to preprocess and fit the obtained X-ray absorption fine structure spectrum to obtain the atomic pair spacing r of the nearest neighbor atom j centered on the specific element i. i-j .

[0054] S7: The obtained average atomic pair spacing parameter is substituted into a preset local lattice distortion formula to calculate the local lattice distortion and average lattice distortion of specific element atoms in the high entropy alloy.

[0055] In this embodiment, the local lattice distortion formula is as follows:

[0056]

[0057] Among them, χ i represents the local lattice distortion of a specific element i, C jrepresents the atomic percentage of the specific element j in the alloy material, r i-j represents the average atomic pair distance of the nearest neighbor atom j centered at a specific element i, Represents the average distance between atomic pairs in alloy materials.

[0058] In this embodiment, S7 specifically includes: substituting the obtained atomic pair spacing parameter into a preset local lattice distortion formula to calculate the local lattice distortion amount and average lattice distortion amount of the specific element atoms of the high entropy alloy, specifically:

[0059] The calculation formula of local lattice distortion is:

[0060]

[0061] The calculation formula for the average lattice distortion is:

[0062] Among them, χ i represents the local lattice distortion of a specific element i, C i It represents the atomic percentage of a specific element i in the alloy material, r i-j represents the average atomic pair distance of the nearest neighbor atom j centered at a specific element i, Represents the average distance between atomic pairs in alloy materials.

[0063] Embodiment 2

[0064] A quantitative calculation system for local lattice distortion of high entropy alloys, such as Figure 7 As shown, it is implemented by a diffraction experiment station of a synchrotron radiation device, a synchrotron radiation X-ray absorption fine structure spectrum experiment station and an electronic device with a central processor. The electronic device is such as a single-chip microcomputer, a smart chip, a personal computer, a smart wearable device, a server, a server cluster, etc., without limitation. It includes a diffraction spectrum collection module 71, a crystal structure determination module 72, a lattice constant calculation module 73, an average atomic pair spacing calculation module 74, a fine structure spectrum collection module 75, an adjacent average atomic pair spacing calculation module 76 and a lattice distortion calculation module 77.

[0065] The diffraction spectrum collection module 71 is used to collect the X-ray diffraction spectrum of the high entropy alloy.

[0066] Specifically, the X-ray diffraction spectrum of CrMnFeCoNi high entropy alloy was collected by the diffraction experimental station of the synchrotron radiation device, with a 2θ angle range of 30-100° and a step size of 0.02°.

[0067] The crystal structure determination module 72 is used to analyze and determine the crystal structure of the high entropy alloy according to the X-ray diffraction spectrum.

[0068] The lattice constant calculation module 73 is used to calculate the lattice constant according to the lattice structure by full spectrum fitting of the X-ray diffraction spectrum.

[0069] The average atomic pair spacing calculation module 74 is used to calculate the average atomic pair spacing according to the geometric relationship between the lattice constant and the crystal structure.

[0070] The fine structure spectrum collection module 75 is used to collect the fine structure spectrum of X-ray absorption of K-edge or L-edge of different alloy elements in the high entropy alloy.

[0071] In this embodiment, relying on the synchrotron radiation X-ray absorption fine structure spectroscopy experimental station, the K-edge XAFS spectra of Cr, Mn, Fe, Co, and Ni elements were collected respectively, and the energy range was -200eV before the absorption edge to 1000eV after the absorption edge.

[0072] The neighboring average atomic pair spacing calculation module 76 is used to analyze and determine the average atomic pair spacing between a specific element and its nearest neighbor element through the fine structure spectrum of the specific element.

[0073] The lattice distortion calculation module 77 is used to substitute the obtained average atomic pair spacing parameter into a preset local lattice distortion formula to calculate the local lattice distortion and average lattice distortion of specific element atoms in the high entropy alloy.

[0074] The implementation process, method and effect of a quantitative calculation system for local lattice distortion of a high entropy alloy in this embodiment are the same as those of a quantitative calculation method for local lattice distortion of a high entropy alloy described in the first embodiment, and will not be repeated here.

[0075] Embodiment 3

[0076] The present invention relates to a computer-readable storage medium, in which instructions are stored. When the instructions are executed, a method for quantitatively calculating the local lattice distortion of a high-entropy alloy is implemented. The process method and effect of the implementation process at runtime are the same as those of the method for quantitatively calculating the local lattice distortion of a high-entropy alloy described in Example 1, and will not be repeated here.

[0077] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0078] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A quantitative calculation method for local lattice distortion of high entropy alloys, characterized in that: include: S1； Collect X-ray diffraction spectra of high entropy alloys; S2: Analyze and determine the crystal structure of the high entropy alloy according to the X-ray diffraction spectrum; S3: Calculating the lattice constant according to the lattice structure by full spectrum fitting of the X-ray diffraction spectrum; S4: calculating an average atomic pair distance according to the geometric relationship between the lattice constant and the crystal structure; S5: Collect the fine structure spectra of X-ray absorption of K-edge or L-edge of different alloying elements in high entropy alloys; S6: analyzing and determining the average atomic pair distance between the specific element and its nearest neighbor element through the fine structure spectrum of the specific element; S7: Substituting the obtained average atomic pair spacing parameter into a preset local lattice distortion formula, the local lattice distortion amount and the average lattice distortion amount of the specific element atoms in the high entropy alloy are calculated.

2. A quantitative calculation method for local lattice distortion of high entropy alloys according to claim 1, characterized in that: The local lattice distortion formula in S7 is as follows: Among them, χ i represents the local lattice distortion of the specific element i, C j represents the atomic percentage of the specific element j in the alloy material, r i-j represents the average atomic pair distance of the nearest neighbor atom j centered on the specific element i, Represents the average distance between atomic pairs in alloy materials.

3. The method for quantitatively calculating local lattice distortion of high entropy alloys according to claim 1, characterized in that: The step S1 specifically includes: collecting the X-ray diffraction spectrum of the CrMnFeCoNi high entropy alloy by means of a diffraction experimental station of a synchrotron radiation device, with a 2θ angle range of 30-100° and a step size of 0.02°.

4. A quantitative calculation method for local lattice distortion of high entropy alloys according to claim 3, characterized in that: The step S2 specifically includes: performing phase analysis on the collected X-ray diffraction spectrum through Highscore software to determine the crystal structure of the high entropy alloy. The crystal structure of the CrMnFeCoNi high entropy alloy is a face-to-face cubic structure.

5. The method for quantitatively calculating local lattice distortion of high entropy alloys according to claim 3, characterized in that: The step S3 specifically includes: using Highscore software to perform full spectrum fitting on the obtained X-ray diffraction spectrum to obtain the lattice constant of the CrMnFeCoNi high entropy alloy.

6. A quantitative calculation method for local lattice distortion of high entropy alloys according to claim 3, characterized in that The step S4 is specifically as follows: according to the geometric relationship between the lattice constant of the cubic structure and the crystal structure The average atomic pair distance is calculated, a is the lattice constant, Average atomic pair distance.

7. A quantitative calculation method for local lattice distortion of high entropy alloys according to claim 3, characterized in that: Specifically, S5 is as follows: relying on the synchrotron radiation X-ray absorption fine structure spectrum experimental station, the fine structure spectra of X-ray absorption of K-edge of Cr, Mn, Fe, Co and Ni elements are collected respectively, with the energy range being -200eV before the absorption edge to 1000eV after the absorption edge.

8. The method for quantitatively calculating local lattice distortion of high entropy alloys according to claim 1, characterized in that: S6 is specifically: using the X-ray absorption fine structure spectrum analysis software Athena and Artemis to pre-process and fit the obtained X-ray absorption fine structure spectrum, and obtain the atomic pair spacing r of the nearest neighbor atom j centered on the specific element i i-j : S7 specifically comprises: substituting the obtained atomic pair spacing parameter into a preset local lattice distortion formula to calculate the local lattice distortion amount and average lattice distortion amount of the specific element atoms in the high entropy alloy, specifically: The calculation formula of the local lattice distortion is: The calculation formula of the average lattice distortion is: Among them, χ i represents the local lattice distortion of the specific element i, C j represents the atomic percentage of the specific element j in the alloy material, C i represents the atomic percentage of the specific element i in the alloy material, r i-j represents the average atomic pair distance of the nearest neighbor atom j centered on the specific element i, Represents the average distance between atomic pairs in alloy materials.

9. A quantitative calculation system for local lattice distortion of high entropy alloys, characterized in that: include: A diffraction spectrum collection module is used to collect X-ray diffraction spectra of high entropy alloys; A crystal structure determination module, used to analyze and determine the crystal structure of the high entropy alloy according to the X-ray diffraction spectrum; A lattice constant calculation module, used to calculate the lattice constant according to the lattice structure by full spectrum fitting of the X-ray diffraction spectrum; An average atomic pair spacing calculation module, used to calculate the average atomic pair spacing according to the geometric relationship between the lattice constant and the crystal structure; Fine structure spectrum collection module, used to collect the fine structure spectrum of X-ray absorption of K-edge or L-edge of different alloy elements in high entropy alloys; A neighboring average atomic pair spacing calculation module is used to analyze and determine the average atomic pair spacing between the specific element and its nearest neighbor element through the fine structure spectrum of the specific element; The lattice distortion calculation module is used to substitute the obtained average atomic pair spacing parameter into a preset local lattice distortion formula to calculate the local lattice distortion and average lattice distortion of the specific element atoms in the high entropy alloy.

10. A computer-readable storage medium, characterized in that: The storage medium stores instructions, which, when executed, execute a method for quantitatively calculating local lattice distortion of a high entropy alloy as described in any one of claims 1-8.

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