Method for calculating maximum magnetic energy product of magnetic material based on Landau theory, storage medium and equipment

Abstract

The invention discloses a method for calculating the maximum magnetic energy product of a magnetic material based on the Landau theory, a storage medium and equipment, and belongs to the field of magnetic material development and performance characterization. The method solves the problems that an existing maximum magnetic energy product obtaining method is high in calculation complexity and experiment cost. The method comprises the following steps: obtaining magnetic unit cells according to a crystal structure of a magnetic material; carrying out geometric optimization on the magnetic unit cells to obtain lattice parameters of paramagnetic unit cells; geometric optimization is carried out on the paramagnetic state unit cells by setting the total magnetic moment m, and unit cell energy corresponding to each total magnetic moment value is obtained; fitting the total magnetic moment value and the energy corresponding to the total magnetic moment value, and obtaining a relation equation between the total magnetic moment value and the magnetic field intensity according to a fitting equation; and the relationship between the magnetization intensity and the magnetic field intensity is obtained by combining the relationship between the total magnetic moment value and the magnetization intensity, and the maximum magnetic energy product of the magnetic material is obtained according to the relationship between the magnetization intensity and the magnetic field intensity. The method can be applied to prediction of the maximum magnetic energy product of the magnetic material.

Description

Technical Field

[0001] The present invention belongs to the field of development and performance characterization of magnetic materials, and particularly relates to a calculation method, storage medium and device for the maximum magnetic energy product of a magnetic material. Background Art

[0002] As an important basic material for modern technology, magnetic materials are widely used in many fields such as electronics, communication, electric power, and automobiles. Among many magnetic materials, rare earth permanent magnet materials have been widely used due to their excellent magnetic properties. However, since neodymium iron boron was discovered in the 1980s, there has been no new breakthrough in the calculation of the maximum magnetic energy product, an important index of permanent magnet materials. Existing methods mainly obtain the maximum magnetic energy product of permanent magnet materials through two means: calculation and experiment. However, the calculation complexity of the maximum magnetic energy product calculation method is relatively high, and obtaining the maximum magnetic energy product of permanent magnet materials through experimental methods has characteristics such as high cost and high technical difficulty. Therefore, there is a need for a method to theoretically predict the maximum magnetic energy product of magnetic materials to guide the experimental design of magnetic materials, so as to solve the problems of high calculation complexity and high experimental cost existing in the existing methods. Summary of the Invention

[0003] The purpose of the present invention is to solve the problems of high calculation complexity and high experimental cost of the existing methods for obtaining the maximum magnetic energy product, and a calculation method, storage medium and device for the maximum magnetic energy product of a magnetic material based on Landau theory are proposed.

[0004] The technical solution adopted by the present invention to solve the above technical problems is: a calculation method for the maximum magnetic energy product of a magnetic material based on Landau theory, the method specifically includes the following steps:

[0005] Step S1: Obtain a magnetic unit cell according to the crystal structure of the magnetic material;

[0006] Step S2: Geometrically optimize the magnetic unit cell to obtain the lattice parameters of the paramagnetic state unit cell;

[0007] Step S3: On the basis of the lattice parameters of the paramagnetic state unit cell, geometrically optimize the paramagnetic state unit cell by setting the total magnetic moment m, and obtain the unit cell energy corresponding to each total magnetic moment value;

[0008] Step S4: Fit the total magnetic moment value and the energy corresponding to the total magnetic moment value according to Landau theory to obtain a fitting equation; take the derivative of the fitting equation to obtain the relationship equation between the total magnetic moment value and the magnetic field strength H;

[0009] According to the relationship between the total magnetic moment value and the magnetization intensity B and the relationship between the total magnetic moment value and the magnetic field strength H, obtain the relationship between the magnetization intensity B and the magnetic field strength H; and then obtain the maximum magnetic energy product of the magnetic material according to the relationship between the magnetization intensity B and the magnetic field strength H.

[0010] Furthermore, the specific process of step S1 is as follows:

[0011] Step S11: Find the crystal structure file of the magnetic material in the crystal structure database;

[0012] Step S12: Visualize the crystal structure of the magnetic material with the help of material crystal structure visualization software, and export the three-dimensional atomic coordinates of the magnetic unit cell in the crystal structure.

[0013] Furthermore, in step S2, the geometric optimization of the magnetic unit cell is realized by using Quantum ESPRESSO.

[0014] Furthermore, the specific process of step S3 is as follows:

[0015] Step S31: Input the lattice parameters of the paramagnetic state unit cell in the input file of Quantum ESPRESSO, set the number of spin degrees of freedom nspin = 2, and set the values of the total magnetic moment m to be m 1 , m 2 , m 3 , m 4 and m 5 , and perform geometric optimization on the paramagnetic state unit cell respectively at each total magnetic moment value;

[0016] Step S32: Extract the unit cell energy E i , i = 1, 2, 3, 4, 5 corresponding to each total magnetic moment value respectively from the output file of Quantum ESPRESSO.

[0017] Furthermore, in step S31, the values of the total magnetic moment m are 0, 2, 4, 6, and 8 respectively.

[0018] Furthermore, the fitting of the total magnetic moment value and the energy corresponding to the total magnetic moment value according to Landau theory is specifically as follows:

[0019] E = m·H = αm 2 + βm 4

[0020] where α and β are fitting coefficients, and H represents the magnetic field strength.

[0021] Furthermore, the relationship between the total magnetic moment value and the magnetization intensity B is:

[0022]

[0023] where μ 0 = 4π×10 -7 T·m / A, μ B = 9.27×10 -24 A·m2 , where \(V\) represents the volume of the unit cell after geometric optimization output by Quantum ESPRESSO when the total magnetic moment value is 0.

[0024] Furthermore, the maximum magnetic energy product of the magnetic material is obtained according to the relationship between the magnetization \(B\) and the magnetic field strength \(H\), specifically:

[0025] Obtain the inflection point of the relationship curve between the magnetization \(B\) and the magnetic field strength \(H\) in the second quadrant. Denote the magnetization corresponding to the inflection point as \(B'\), and the magnetic field strength corresponding to the inflection point as \(H'\). Then the maximum magnetic energy product of the magnetic material is the product of \(B'\) and \(H'\).

[0026] A computer storage medium stores at least one instruction, and the at least one instruction is loaded and executed by a processor to implement the above-mentioned calculation method for the maximum magnetic energy product of a magnetic material based on Landau theory.

[0027] A calculation device for the maximum magnetic energy product of a magnetic material based on Landau theory, the device includes a processor and a memory, and the memory stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement the above-mentioned calculation method for the maximum magnetic energy product of a magnetic material based on Landau theory.

[0028] The beneficial effects of the present invention are:

[0029] (1) The present invention adopts the calculation method of first-principles. Only the basic crystal structure information of the magnetic material is required, and no other additional experimental parameters are needed to calculate the atomic positions, electronic states, and total energy of the system, greatly reducing the complexity of the calculation method;

[0030] (2) The method of the present invention predicts the maximum magnetic energy product of the magnetic material at 0K through theoretical calculation, providing a theoretical guidance and design basis for developing new material systems;

[0031] (3) The implementation of the method of the present invention only requires computer experimental equipment to quantitatively design the magnetic material, significantly reducing the experimental cost and excluding the interference of complex experimental factors, with high research efficiency and the calculation method having universality. Description of the Drawings

[0032] Figure 1 is a flowchart of the calculation method for the maximum magnetic energy product of a magnetic material based on Landau theory of the present invention;

[0033] Figure 2 is the \(E - m\) curve before and after fitting of bcc - Fe;

[0034] tot_magnetization represents the total magnetic moment value, and Energy represents the energy;

[0035] Figure 3 is the hysteresis loop of bcc-Fe at 0K (the shaded area is the schematic area of the maximum magnetic energy product);

[0036] Figure 4 is the E-m curve of hcp-Co before and after fitting;

[0037] Figure 5 is the hysteresis loop of hcp-Co at 0K (the shaded area is the schematic area of the maximum magnetic energy product). Detailed implementation manners

[0038] Detailed implementation manner one: Combine Figure 1 to illustrate this implementation manner. A calculation method for the maximum magnetic energy product of a magnetic material based on Landau theory described in this implementation manner specifically includes the following steps:

[0039] Step S1, obtain the magnetic unit cell according to the crystal structure of the magnetic material;

[0040] Step S2, perform geometric optimization on the magnetic unit cell to obtain the lattice parameters of the paramagnetic state unit cell (optimize the magnetic unit cell without setting magnetic parameters, and what is obtained is the paramagnetic state unit cell);

[0041] Step S3, based on the lattice parameters of the paramagnetic state unit cell, perform geometric optimization on the paramagnetic state unit cell by setting the total magnetic moment m from low to high, and obtain the unit cell energy corresponding to each total magnetic moment value respectively;

[0042] Step S4, perform fitting on the total magnetic moment value and the energy corresponding to the total magnetic moment value according to Landau theory to obtain a fitting equation; perform differentiation on the fitting equation (that is, perform differentiation on both the left and right ends of the fitting equation with respect to the total magnetic moment m) to obtain the relationship equation between the total magnetic moment value and the magnetic field strength H;

[0043] According to the relationship between the total magnetic moment value and the magnetization intensity B and the relationship between the total magnetic moment value and the magnetic field strength H, obtain the relationship between the magnetization intensity B and the magnetic field strength H; then obtain the maximum magnetic energy product of the magnetic material according to the relationship between the magnetization intensity B and the magnetic field strength H.

[0044] Detailed implementation manner two: The difference between this implementation manner and detailed implementation manner one is that the specific process of step S1 is as follows:

[0045] Step S11, find the crystal structure file of the magnetic material in the crystal structure database (ICSD);

[0046] Step S12, visualize the crystal structure of the magnetic material with the help of material crystal structure visualization software, and export the three-dimensional atomic coordinates of the magnetic unit cell in the crystal structure.

[0047] Other steps and parameters are the same as those in detailed implementation manner one.

[0048] Embodiment 3: The difference between this embodiment and Embodiment 1 or 2 is that in step S2, the geometric optimization of the magnetic unit cell is realized by using Quantum ESPRESSO.

[0049] Other steps and parameters are the same as those in Embodiment 1 or 2.

[0050] Quantum ESPRESSO is an open-source quantum mechanics calculation software package based on first principles.

[0051] Embodiment 4: The difference between this embodiment and any one of Embodiments 1 to 3 is that the specific process of step S3 is as follows:

[0052] Step S31: Input the lattice parameters of the paramagnetic state unit cell in the input file of Quantum ESPRESSO, set the number of spin degrees of freedom nspin = 2, and set the values of the total magnetic moment m to be m 1 , m 2 , m 3 , m 4 and m 5 respectively, and perform geometric optimization on the paramagnetic state unit cell at each total magnetic moment value;

[0053] Step S32: Extract the unit cell energy E i corresponding to each total magnetic moment value from the output file of Quantum ESPRESSO, where i = 1, 2, 3, 4, 5.

[0054] Other steps and parameters are the same as those in any one of Embodiments 1 to 3.

[0055] Embodiment 5: The difference between this embodiment and any one of Embodiments 1 to 4 is that in step S31, the values of the total magnetic moment m are 0, 2, 4, 6, and 8 respectively.

[0056] Other steps and parameters are the same as those in any one of Embodiments 1 to 4.

[0057] Embodiment 6: The difference between this embodiment and any one of Embodiments 1 to 5 is that the fitting of the total magnetic moment value and the energy corresponding to the total magnetic moment value according to Landau theory is specifically as follows:

[0058] E = m·H = αm 2 + βm 4

[0059] where α and β are fitting coefficients, and H represents the magnetic field strength.

[0060] Other steps and parameters are the same as those in any one of Embodiments 1 to 5.

[0061] Embodiment VII: The difference between this embodiment and any one of Embodiments I - VI is that the relationship between the total magnetic moment value and the magnetization intensity B is as follows:

[0062]

[0063] where μ 0 = 4π×10 -7 T·m / A, μ B = 9.27×10 -24 A·m 2 , T represents Tesla, A represents Ampere, and V represents the volume of the geometrically optimized unit cell output by Quantum ESPRESSO when the total magnetic moment value is 0.

[0064] Other steps and parameters are the same as any one of Embodiments I - VI.

[0065] Embodiment VIII: The difference between this embodiment and any one of Embodiments I - VII is that the maximum magnetic energy product of the magnetic material is obtained according to the relationship between the magnetization intensity B and the magnetic field intensity H, specifically:

[0066] Obtain the inflection point of the relationship curve between the magnetization intensity B and the magnetic field intensity H in the second quadrant. Denote the magnetization intensity corresponding to the inflection point as B', and the magnetic field intensity corresponding to the inflection point as H'. Then the maximum magnetic energy product of the magnetic material is the product of B' and H'.

[0067] Other steps and parameters are the same as any one of Embodiments I - VII.

[0068] Embodiment IX: A computer storage medium in this embodiment, where at least one instruction is stored in the storage medium, and the at least one instruction is loaded and executed by a processor to implement the described calculation method for the maximum magnetic energy product of a magnetic material based on Landau theory.

[0069] It should be understood that the instructions include computer program products, software, or computerized methods corresponding to any method described in the present invention; the instructions can be used to program a computer system or other electronic devices. The computer storage medium can include a readable medium on which the instructions are stored, which can include but are not limited to magnetic storage media, optical storage media; magneto - optical storage media include read - only memory, random access memory, erasable programmable memory such as, and flash memory layers, or other types of media suitable for storing electronic instructions.

[0070] Embodiment 10: This embodiment is a calculation device for the maximum magnetic energy product of a magnetic material based on Landau theory. The device includes a processor and a memory. It should be understood that any device including a processor and a memory described in the present invention may also include other units and modules for display, interaction, processing, control, etc. through signals or instructions and other functions;

[0071] At least one instruction is stored in the memory, and the at least one instruction is loaded and executed by the processor to implement the calculation method for the maximum magnetic energy product of a magnetic material based on Landau theory.

[0072] The embodiments described in the technical solutions of the present invention are only a part of the embodiments of the present invention, rather than all embodiments. For those of ordinary skill in the art, all other embodiments obtained without creative efforts shall fall within the scope of protection of the present invention.

[0073] Next, the technical solutions of the present invention will be described in detail and completely in combination with the drawings and specific embodiments.

[0074] Embodiment 1:

[0075] Referring to Figure 1 As shown, the present invention proposes a calculation method for the maximum magnetic energy product of a magnetic material based on Landau theory, specifically including the following steps:

[0076] Step S1. Obtain a magnetic unit cell according to the crystal structure of bcc-Fe:

[0077] Step S11. Find the crystal structure file of bcc-Fe in the crystal structure database (ICSD);

[0078] Step S12. Visualize the crystal structure of the magnetic material with the help of material crystal structure visualization software, and export the three-dimensional atomic coordinates of the magnetic unit cell in the crystal structure.

[0079] Step S2. Geometrically optimize the magnetic unit cell through the first-principles Quantum ESPRESSO calculation software package to obtain the lattice parameters of the paramagnetic state unit cell (optimizing the magnetic unit cell without setting magnetic parameters, the obtained is the paramagnetic state unit cell);

[0080] Step S3. Based on the lattice parameters of the paramagnetic state unit cell, geometrically optimize the paramagnetic state unit cell by setting the total magnetic moment m from low to high, and obtain the unit cell energy corresponding to each total magnetic moment value respectively;

[0081] Step S31: Input the lattice parameters of the paramagnetic state unit cell in the input file of Quantum ESPRESSO, set the number of spin degrees of freedom nspin = 2, set the values of the total magnetic moment m to be 0, 2, 4, 6, and 8 respectively, and perform geometric optimization on the paramagnetic state unit cell at each total magnetic moment value;

[0082] Step S32: Extract the unit cell energy corresponding to each total magnetic moment value from the output file of Quantum ESPRESSO.

[0083] Step S4: Fit the total magnetic moment value and the energy corresponding to the total magnetic moment value according to the Landau theory to obtain a fitting equation, as Figure 2 shown:

[0084] E = m·H = αm 2 +βm 4

[0085] where α and β are fitting coefficients, and H represents the magnetic field strength.

[0086] Derive the fitting equation to obtain the relationship equation between the total magnetic moment value and the magnetic field strength H;

[0087] According to the relationship between the total magnetic moment value and the magnetization intensity B and the relationship between the total magnetic moment value and the magnetic field strength H, obtain the relationship between the magnetization intensity B and the magnetic field strength H, as Figure 3 shown;

[0088] The relationship between the total magnetic moment value and the magnetization intensity B is:

[0089]

[0090] where μ 0 = 4π×10 -7 T·m / A, μ B = 9.27×10 -24 A·m 2 ,

[0091] Then, obtain the maximum magnetic energy product of the magnetic material according to the relationship between the magnetization intensity B and the magnetic field strength H:

[0092] Obtain the inflection point of the relationship curve between the magnetization intensity B and the magnetic field strength H in the second quadrant, denote the magnetization intensity corresponding to the inflection point as B', and denote the magnetic field strength corresponding to the inflection point as H'. Then, the maximum magnetic energy product of the magnetic material is the product of B' and H'. The maximum magnetic energy product of bcc-Fe at 0K is approximately 4.36 MGOe.

[0093] Example 2:

[0094] Refer to Figure 1As shown in the figure, the present invention proposes a calculation method for the maximum magnetic energy product of a magnetic material based on Landau theory, specifically including the following steps:

[0095] Step S1: Obtain the magnetic unit cell according to the crystal structure of hcp-Co:

[0096] Step S11: Find the crystal structure file of hcp-Co in the Inorganic Crystal Structure Database (ICSD);

[0097] Step S12: Visualize the crystal structure of the magnetic material with the help of material crystal structure visualization software, and export the three-dimensional atomic coordinates of the magnetic unit cell in the crystal.

[0098] Step S2: Geometrically optimize the magnetic unit cell through the first-principles Quantum ESPRESSO calculation software package to obtain the lattice parameters of the paramagnetic state unit cell (optimizing the magnetic unit cell without setting magnetic parameters will obtain the paramagnetic state unit cell);

[0099] Step S3: Based on the lattice parameters of the paramagnetic state unit cell, geometrically optimize the paramagnetic state unit cell by setting the total magnetic moment m from low to high, and obtain the unit cell energy corresponding to each total magnetic moment value respectively;

[0100] Step S31: Input the lattice parameters of the paramagnetic state unit cell in the input file of Quantum ESPRESSO, set the number of spin degrees of freedom nspin = 2, and set the values of the total magnetic moment m to be 0, 2, 4, 6, and 8 respectively. Geometrically optimize the paramagnetic state unit cell at each total magnetic moment value;

[0101] Step S32: Extract the unit cell energy corresponding to each total magnetic moment value from the output file of Quantum ESPRESSO respectively.

[0102] Step S4: Fit the total magnetic moment value and the energy corresponding to the total magnetic moment value according to Landau theory to obtain a fitting equation, as Figure 4 shown:

[0103] E = m·H = αm 2 +βm 4

[0104] where α and β are fitting coefficients, and H represents the magnetic field strength.

[0105] Derive the fitting equation to obtain the relationship equation between the total magnetic moment value and the magnetic field strength H;

[0106] According to the relationship between the total magnetic moment value and the magnetization intensity B and the relationship between the total magnetic moment value and the magnetic field strength H, obtain the relationship between the magnetization intensity B and the magnetic field strength H, as Figure 5 shown;

[0107] The relationship between the total magnetic moment value and the magnetization intensity B is as follows:

[0108]

[0109] where μ 0 = 4π×10 -7 T·m / A, μ B = 9.27×10 -24 A·m 2 ,

[0110] Then, based on the relationship between the magnetization intensity B and the magnetic field intensity H, the maximum magnetic energy product of the magnetic material is obtained:

[0111] The inflection point of the relationship curve between the magnetization intensity B and the magnetic field intensity H in the second quadrant is obtained. Denote the magnetization intensity corresponding to the inflection point as B', and the magnetic field intensity corresponding to the inflection point as H'. Then, the maximum magnetic energy product of the magnetic material is the product of B' and H'. The maximum magnetic energy product of hcp-Co at 0K is approximately 0.16 MGOe.

[0112] In summary, based on the Landau second-order phase transition theory, and using the conversion relationship between the magnetization intensity B and the magnetic moment m of the unit cell atoms, the hysteresis loop of the magnetic material at 0K can be calculated, and the corresponding maximum magnetic energy product can be calculated. The calculated maximum magnetic energy product of bcc-Fe at 0K is approximately 4.36 MGOe, and the maximum magnetic energy product of hcp-Co at 0K is approximately 0.16 MGOe. The method of the present invention has guiding significance for the prediction of new permanent magnetic materials.

[0113] The above calculation examples of the present invention are only used to illustrate in detail the calculation model and calculation process of the present invention, rather than limiting the implementation manner of the present invention. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation manners here. Any obvious changes or modifications derived from the technical solution of the present invention still fall within the protection scope of the present invention.

Claims

1. A method for calculating the maximum magnetic energy product of a magnetic material based on Landau theory, characterized in that: The method specifically comprises the following steps: Step S1, obtaining a magnetic unit cell according to the crystal structure of the magnetic material; Step S2, performing geometric optimization on the magnetic unit cell to obtain the lattice parameters of the paramagnetic unit cell; Step S3, based on the lattice parameters of the paramagnetic state unit cell, the paramagnetic state unit cell is geometrically optimized by setting the total magnetic moment m, and the unit cell energy corresponding to each total magnetic moment value is obtained respectively; Step S4, fitting the total magnetic moment value and the energy corresponding to the total magnetic moment value according to Landau theory to obtain a fitting equation; and derivatizing the fitting equation to obtain a relationship equation between the total magnetic moment value and the magnetic field intensity H; According to the relationship between the total magnetic moment value and the magnetization intensity B and the relationship between the total magnetic moment value and the magnetic field intensity H, the relationship between the magnetization intensity B and the magnetic field intensity H is obtained; and then according to the relationship between the magnetization intensity B and the magnetic field intensity H, the maximum magnetic energy product of the magnetic material is obtained.

2. The method for calculating the maximum magnetic energy product of a magnetic material based on Landau theory according to claim 1, characterized in that: The specific process of step S1 is as follows: Step S11, finding the crystal structure file of the magnetic material in the crystal structure database; Step S12: Visualize the crystal structure of the magnetic material using material crystal structure visualization software, and derive the three-dimensional atomic coordinates of the magnetic unit cell in the crystal structure.

3. The method for calculating the maximum magnetic energy product of a magnetic material based on Landau theory according to claim 1, characterized in that: In the step S2, the geometry optimization of the magnetic unit cell is achieved by using Quantum ESPRESSO.

4. The method for calculating the maximum magnetic energy product of a magnetic material based on Landau theory according to claim 3, characterized in that: The specific process of step S3 is: Step S31, input the lattice parameters of the paramagnetic state unit cell in the input file of Quantum ESPRESSO, set the number of spin degrees of freedom nspin=2, set the values ​​of the total magnetic moment m to be m1, m2, m3, m4 and m5 respectively, and perform geometric optimization on the paramagnetic state unit cell at each total magnetic moment value; Step S32: extract the unit cell energy E corresponding to each total magnetic moment value from the output file of Quantum ESPRESSO. i , i=1, 2, 3, 4, 5.

5. The method for calculating the maximum magnetic energy product of a magnetic material based on Landau theory according to claim 4, characterized in that: In step S31, the values ​​of the total magnetic moment m are 0, 2, 4, 6 and 8 respectively.

6. The method for calculating the maximum magnetic energy product of a magnetic material based on Landau theory according to claim 1, characterized in that: The total magnetic moment value and the energy corresponding to the total magnetic moment value are fitted according to the Landau theory, specifically: E=m·H=αm 2 +βm 4 Among them, α and β are fitting coefficients, and H represents the magnetic field intensity.

7. The method for calculating the maximum magnetic energy product of a magnetic material based on Landau theory according to claim 1, characterized in that: The relationship between the total magnetic moment value and the magnetization intensity B is: Where, μ0=4π×10 -7 T·m / A,μ B =9.27×10 -24 A.m 2 , V represents the volume of the geometry-optimized unit cell output by QuantumESPRESSO when the total magnetic moment value is 0.

8. The method for calculating the maximum magnetic energy product of a magnetic material based on Landau theory according to claim 1, characterized in that: The maximum magnetic energy product of the magnetic material is obtained according to the relationship between the magnetization intensity B and the magnetic field intensity H, specifically: The inflection point of the relationship curve between the magnetization intensity B and the magnetic field intensity H in the second quadrant is obtained, and the magnetization intensity corresponding to the inflection point is recorded as B', and the magnetic field intensity corresponding to the inflection point is recorded as H'. The maximum magnetic energy product of the magnetic material is the product of B' and H'.

9. A computer storage medium, characterized in that The storage medium stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement a method for calculating the maximum magnetic energy product of a magnetic material based on Landau theory as described in any one of claims 1 to 8.

10. A device for calculating the maximum magnetic energy product of magnetic materials based on Landau theory, characterized in that: The device includes a processor and a memory, wherein the memory stores at least one instruction, and the at least one instruction is loaded and executed by the processor to implement a method for calculating the maximum magnetic energy product of a magnetic material based on Landau theory as described in any one of claims 1 to 8.

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