WO2022174492A1

WO2022174492A1 - Prediction method for adjustment and control effect of additive element on solid solubility of target element, and application thereof

Info

Publication number: WO2022174492A1
Application number: PCT/CN2021/083337
Authority: WO
Inventors: 王瑨; 马堂鹏; 周吉学; 程开明; 詹成伟; 赵国辰; 孙佳星; 刘运腾; 吴建华; 修大鹏; 王西涛
Original assignee: 山东省科学院新材料研究所
Priority date: 2021-02-18
Filing date: 2021-03-26
Publication date: 2022-08-25
Also published as: CN112992287A; CN112992287B

Abstract

A prediction method for the adjustment and control effect of an additive element in an alloy on the solid solubility of a target element, and an application thereof. The prediction method comprises: respectively constructing metal base body, binary solid solution and ternary solid solution crystal models, and monatomic models of a base body element, a target element and an additive element, wherein a ternary solid solution is selected from a crystal cell in which first coordination layers of the target element and the additive element have no shared atoms; acquiring the crystal cell volumes and cohesive energy of the above models, and the inner volumes and embedding energy of the first coordination layers by means of structure optimization and static self-consistency of first-principle calculation, and observing a numerical evolution trend during the process of a metal base solid solution expanding from binary to ternary caused by the additive element; and introducing the differential electron density of the ternary solid solution according to the numerical evolution trend, so as to realize effective prediction for the adjustment and control effect of the additive element on the solid solubility of the target element. By means of theoretical calculation, an element design basis is provided for the development of a new alloy, thereby reducing the blindness of alloy design.

Description

Prediction method and application of adding elements to control the solid solubility of target elements

technical field

The invention relates to the technical field of metal materials, in particular to a method for predicting the effect of adding elements in an alloy on the regulation and control of the solid solubility of a target element and its application.

Background technique

The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not necessarily be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person of ordinary skill in the art.

With the industrial development of 3C electronic equipment, vehicles and other fields, the application requirements of metal materials are becoming more and more extensive. However, the existing mature alloy grades are difficult to meet the performance requirements of the application, so there is an urgent need to carry out the design and development of new alloys. Solid solution strengthening is one of the main ideas to improve the mechanical properties of alloys. The alloy design developed under this idea takes the solid solubility of alloy elements as the core parameter. For binary alloys, the solid solubility of alloying elements can be directly predicted according to the Hume-Rothery rule and its derivatives.

The inventor's research found that when the alloy is expanded from binary to multi-element, the addition of elements will change the solid solubility of alloy elements in the original binary alloy, and the change in solid solubility will affect the solid solution strengthening effect of the alloy. Therefore, how to determine the additive elements in multi-element alloys from the perspective of regulating the solid solubility of target elements is of great significance for the design of new alloys.

Moreover, due to the lack of a theory to predict the effect of adding elements on the regulation of the solid solubility of the target element, the alloy design work in this area can only be carried out through the traditional experimental "trial and error method", which consumes a lot of time and resources.

SUMMARY OF THE INVENTION

In order to solve the problems existing in the prior art, the present invention proposes a method for predicting the effect of adding elements in the alloy on the regulation of the solid solubility of the target element. Through first-principles calculation, the structure and energy parameters of the solid solution phase in the alloy are obtained, and combined with The electron density can accurately and efficiently predict the control effect of the added element on the solid solubility of the target element.

Specifically, the present invention is achieved through the following technical solutions:

A first aspect of the present invention provides a method for predicting the effect of adding elements on the regulation and control of the solid solubility of target elements, including:

Build metal matrix, binary solid solution, ternary solid solution crystal models, and single-atom models of matrix elements, target elements, and additive elements, respectively;

Through the structural optimization and static self-consistency of first-principles calculations, the unit cell volume and cohesive energy of the metal matrix, binary solid solution, and ternary solid solution, as well as the inner volume and intercalation energy of the first coordination layer, are obtained. The ternary solid solution is selected from There is no unit cell of shared atoms in the first coordination layer of the target element and the additive element, and the numerical evolution trend of the solid solution from binary to ternary caused by the additive element is analyzed.

According to the numerical evolution trend of the solid solution, the differential electron density of the ternary solid solution is obtained through the structural optimization and static self-consistency and non-self-consistency of the first-principles calculation. Unit cell to analyze the distribution of valence electrons.

In a second aspect of the present invention, there is provided an application of a method for predicting the effect of adding elements on the regulation and control of the solid solubility of a target element in the field of alloy design.

In a third aspect of the present invention, an alloy design method capable of directional regulation of the solid solubility of a target element is provided, including: a method for predicting the regulation effect of adding elements on the solid solubility of the target element.

One or more embodiments of the present invention have the following beneficial effects:

1) Predicting the regulation effect of added elements on the solid solubility of target elements through theoretical calculation, providing element design basis for the development of new alloys, reducing the blindness of alloy design, saving alloy research and development costs, and improving research and development efficiency.

2) The study found that the prediction method of the present application has a more accurate prediction effect in predicting the effect of adding elements in the Mg alloy on the regulation and control of the solid solubility of the target element.

Description of drawings

The accompanying drawings forming a part of the present invention are used to provide further understanding of the present invention, and the exemplary embodiments of the present invention and their descriptions are used to explain the present invention, and do not constitute an improper limitation of the present invention. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein:

Fig. 1 is the flow chart of embodiment 1 of the present invention predicting the effect of adding elements in the alloy to control the solid solubility of target elements;

Fig. 2 is the Mg matrix crystal model of the embodiment 2 of the present invention;

Fig. 3 is the binary Mg-Zn solid solution crystal model of the embodiment 2 of the present invention;

4 is a ternary Mg-Zn-X solid solution crystal model of Example 2 of the present invention (X=Ca, Y, Sn, Zn and X do not share atoms in the first coordination layer);

Fig. 5 is the Mg matrix, binary Mg-Zn solid solution, ternary Mg-Zn-X solid solution (X=Ca, Y, Sn) unit cell volume of the embodiment of the present invention 2;

6 is the cohesive energy of the Mg matrix, binary Mg-Zn solid solution, and ternary Mg-Zn-X solid solution (X=Ca, Y, Sn) of Example 2 of the present invention;

7 is the inner volume of the first coordination layer in the Mg matrix, binary Mg-Zn solid solution, and ternary Mg-Zn-X solid solution (X=Ca, Y, Sn) of Example 2 of the present invention;

Fig. 8 is the embedding energy of the first coordination layer in the Mg matrix, binary Mg-Zn solid solution, and ternary Mg-Zn-X solid solution (X=Ca, Y, Sn) of Example 2 of the present invention;

9 is the differential electron density in the ternary Mg-Zn-Ca solid solution (Zn and Ca are the nearest neighbors to each other) of Example 2 of the present invention;

10 is the differential electron density in the ternary Mg-Zn-Y solid solution (Zn and Y are the nearest neighbors to each other) of Example 2 of the present invention.

Detailed ways

The present invention will be further described below in conjunction with specific embodiments. It should be understood that these examples are only used to illustrate the present invention and not to limit the scope of the present invention. In the following examples, the experimental methods without specific conditions are usually in accordance with conventional conditions or in accordance with the conditions suggested by the manufacturer.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present disclosure. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural as well, furthermore, it is to be understood that when the terms "comprising" and/or "including" are used in this specification, it indicates that There are features, steps, operations, devices, components and/or combinations thereof.

For binary alloys, the solid solubility of alloying elements can be directly predicted according to the Hume-Rothery rule and its derivatives. When the alloy is expanded from binary to multi-element, the addition of elements will change the solid solubility of alloy elements in the original binary alloy, and the change of solid solubility will affect the solid solution strengthening effect of the alloy. Therefore, how to determine the additive elements in multi-element alloys from the perspective of regulating the solid solubility of target elements is of great significance for the design of new alloys.

To this end, the present invention proposes a method for predicting the effect of adding elements on the regulation of the solid solubility of a target element. Through first-principles calculation, the structure and energy parameters of the solid solution phase in the alloy are obtained, and combined with the electron density, the prediction can be accurately and efficiently predicted. Controlling effect of added elements in alloys on the solid solubility of target elements.

Through the structural optimization and static self-consistency of the first-principles calculation, the unit cell volume and cohesive energy of the above model and the inner volume and embedding energy of the first coordination layer are obtained. The ternary solid solution is selected from the target element and the added element. There is no unit cell of shared atoms in the bit layer, and the numerical evolution trend of solid solution expansion from binary to ternary caused by adding elements is analyzed.

In one or more embodiments of the present invention, if the added element does not cause the parameter value in the original binary solid solution to change to the metal matrix, it is predicted that the added element has the effect of reducing the solid solubility of the target element in the metal matrix; if the added element As a result, the parameter values in the original binary solid solution are transformed to the metal matrix, then the differential electron density in the ternary solid solution is obtained through the structural optimization and static self-consistency and non-self-consistency of the first-principles calculation, and the ternary solid solution is selected from the target element. And the unit cell where the element is the nearest neighbor to each other, and the distribution of valence electrons is analyzed.

Preferably, if the aggregation of valence electrons does not occur between the target element and the additive element in the differential electron density, it is predicted that the additive element has the effect of improving the solid solubility of the target element in the metal matrix; if the aggregation of valence electrons occurs, it is predicted that The addition of elements has the effect of reducing the solid solubility of the target element in the metal matrix.

In one or more embodiments of the present invention, the metal matrix crystal model is a pure metal cell constructed according to the experimentally determined space group, lattice parameters and atomic coordinates, and is extended into a supercell, each basis vector The expansion factor in the direction must be greater than or equal to 3;

Preferably, the binary solid solution crystal model is to replace any atom in the pure metal supercell with the target element;

Preferably, the crystal model of the ternary solid solution is to replace two atoms in the pure metal supercell with the target element and the additive element respectively;

Preferably, the ternary solid solution crystal model includes no shared atoms in the first coordination layer of the target element and the additive element, and the target element and the additive element are nearest neighbor atoms to each other;

Preferably, for the single-atom model, an orthorhombic lattice needs to be constructed, and the lattice parameters meet the following conditions:

a≠b≠c, atoms can be fixed at any position in the lattice.

In one or more embodiments of the present invention, the calculation parameters include: the plane wave truncation energy is greater than or equal to 350 eV, the grid density of the Brillouin zone is greater than or equal to 9×9×5; the total energy convergence criterion of the system is less than or equal to 5×10 ^{− 6} eV/cell, the single-atom force convergence criterion is less than or equal to

In one or more embodiments of the present invention, first-principles calculation software is used to perform static self-consistency on the optimized unit cell to obtain the unit cell volume and total energy of the metal matrix, binary and ternary solid solutions. The atomic model implements static self-consistency, obtains the total energy of single atoms of matrix elements, target elements and added elements, and calculates the cohesive energy of each system.

In one or more embodiments of the present invention, the identified atoms in the first coordination layer are removed from the metal matrix, the binary solid solution, and the optimized unit cell of the selected ternary solid solution, respectively, and the first coordination layer is used. The principle calculation software implements static self-consistency, obtains the total energy of the system, and calculates the embedded energy in the first coordination layer.

In one or more embodiments of the present invention, first-principles calculation software is used to perform static self-consistency and non-self-consistency on the optimized unit cell of the ternary solid solution selected above to calculate the differential electron density.

In one or more embodiments of the present invention, the metal matrix is Mg, the target element is Zn, and the additive element is selected from Ca, Sn, and Y.

In one or more embodiments of the present invention, the method for predicting the effect of adding elements on the regulation and control of the solid solubility of the target element includes:

Model construction: Build Mg matrix, binary Mg-based solid solution, ternary Mg-based solid solution lattice models, and single-atom models of Mg, target elements, and added elements;

Calculation process: optimize the model, calculate the unit cell volume and total energy of Mg matrix, binary and ternary Mg-based solid solutions, and the total energy of single atoms of Mg, target elements, and added elements, and obtain the cohesive energy of each system;

In the optimized unit cell of Mg matrix, the first coordination layer of any Mg atom was identified, and the first coordination layer of the target element in the optimized unit cell of binary and ternary Mg-based solid solution was identified respectively. The inner volume of the first coordination layer; the identified atoms in the first coordination layer are removed from the optimized unit cells of the Mg matrix, the binary Mg-based solid solution and the selected ternary Mg-based solid solution, respectively, to obtain the total system volume. energy and the intercalation energy in the first coordination layer;

According to the above four parameters, the numerical evolution trend of the Mg-based solid solution from binary expansion to ternary caused by the addition of elements is clearly defined. If the addition of elements causes the parameter values in the original binary Mg-based solid solution to change to the Mg matrix, the above The selected differential electron density of the ternary Mg-based solid solution finally achieves an effective prediction for the control effect of the added elements in the Mg alloy on the solid solubility of the target element.

Specifically, including:

1. Model construction:

The Mg matrix, binary Mg-based solid solution, ternary Mg-based solid solution lattice model, and single-atom models of Mg, target elements, and added elements were constructed by visual modeling software. The modeling methods are as follows:

According to the experimentally determined space group, lattice parameters and atomic coordinates, a pure Mg cell was constructed and extended into a supercell. Wherein, the expansion coefficient in each base vector direction must be greater than or equal to 3. This is used as the Mg matrix crystal model.

Any atom in the pure Mg supercell is replaced with the target element as a binary Mg-based solid solution crystal model.

The two atoms in the pure Mg supercell were replaced by the target element and the additive element, respectively, to form a ternary Mg-based solid solution crystal model. This model needs to construct two kinds of atomic positional relationships corresponding to the target element and the added element: one is that there is no shared atom in the first coordination layer of the two, and the other is that the two are the nearest neighbor atoms to each other.

For the single-atom model, an orthorhombic lattice needs to be constructed, and the lattice parameters satisfy the following conditions:

a≠b≠c. In this model, atoms can be fixed anywhere within the lattice.

Second, the calculation process:

First-principles calculation software was used to optimize the structure of Mg matrix, binary and ternary Mg-based solid solution models, respectively. Among them, the ternary Mg-based solid solution selects the unit cell with no shared atoms in the first coordination layer of the target element and the additive element.

The calculation parameters are required as follows: the plane wave truncation energy is greater than or equal to 350eV, and the grid density of the Brillouin zone is greater than or equal to 9×9×5. The total energy convergence criterion of the system is less than or equal to 5×10 ^-6 eV/cell, and the single-atom force convergence criterion is less than or equal to

Using first-principles calculation software, the optimized unit cell was statically self-consistent, and the unit cell volume and total energy of Mg matrix, binary and ternary Mg-based solid solutions were obtained. Further, the static self-consistency of the single-atom model was implemented to obtain the single-atom total energy of Mg, the target element, and the added element, and the cohesive energy of each system was calculated according to the following formula.

Among them, _E ^total is the total system energy of the optimized unit cell, Ne is the number of elements contained in the structure, _ni is the number of atoms of each element in the structure,

is the monatomic energy of the element.

In the optimized unit cell of Mg matrix, the first coordination layer of any Mg atom was identified, and the first coordination layer of the target element in the optimized unit cell of binary and ternary Mg-based solid solution was identified respectively. Calculate the inner volume of the first coordination layer in each system.

The atoms in the identified first coordination layer were removed from the optimized unit cells of the Mg matrix, the binary Mg-based solid solution, and the selected ternary Mg-based solid solution, respectively, and the first-principles calculation software was used to implement them again. Statically self-consistent, the total energy of the system is obtained, and the intercalation energy in the first coordination layer is calculated according to the following formula.

Among them, A is the removed part,

In order to fully optimize the cohesive energy of the unit cell,

is the cohesive energy of the remainder of the unit cell after A is removed.

Based on the differences in unit cell volume, cohesive energy, and the volume and intercalation energy of the first coordination layer between the Mg matrix and the binary Mg-based solid solution, it is clear that the above aspects of the Mg-based solid solution in the process of expanding from binary to ternary data trends.

If the addition of elements causes the parameter values in the original binary Mg-based solid solution to change to the Mg matrix, first-principles calculation software is used to optimize the structure of the ternary Mg-based solid solution model in which the target element and the added element are the nearest neighbors to each other. Static self-consistency and non-self-consistency are implemented for the optimized structure, and the differential electron density is calculated according to the following formula.

Δρ=ρ _sc _{-ρ nsc}

Among them, ρ _sc is the electron density after the optimized structure is statically self-consistent, and ρ _{nsc is} the non-self-consistent electron density.

The differential electron density between the target element and the additive element in the structure is evaluated, and the regulating effect of the additive element on the solid solubility of the target element is determined.

In a third aspect of the present invention, an alloy design method capable of directional regulation of the solid solubility of a target element is provided, including a method for predicting the regulation effect of adding elements on the solid solubility of the target element.

The present invention will be further described in detail below with reference to specific embodiments. It should be pointed out that the specific embodiments are intended to explain rather than limit the present invention.

Example 1

Figure 1 shows the flow chart of the method for predicting the effect of adding elements on the regulation and control of the solid solubility of the target element in this embodiment. First, the lattice models of metal matrix, binary solid solution and ternary solid solution are constructed. Secondly, through the structural optimization and static self-consistency of first-principles calculations, the unit cell volume and cohesive energy of the above model and the inner volume and embedding energy of the first coordination layer are obtained. According to the above four parameters, the numerical evolution trend in the process of solid solution expanding from binary to ternary caused by the addition of elements is clearly defined. If the addition of elements causes the parameter values in the original binary solid solution to change to the metal matrix, the differential electron density in the ternary solid solution is introduced, and finally the effect of the addition elements in the alloy on the regulation of the solid solubility of the target element can be effectively predicted.

Example 2

Taking Ca, Y, Sn and Zn as examples, the regulating effects of Ca, Y, Sn on the solid solubility of Zn in Mg alloys were predicted respectively.

Taking Zn as the target element and Ca, Y, Sn as the additive elements, a Mg matrix, a binary Mg-Zn solid solution model, and a ternary Mg-Zn-Ca, Mg with no shared atoms in the first coordination layer of the target element and the additive element were constructed. -Zn-Y, Mg-Zn-Sn solid solution model is shown in Figure 2-4.

The structure optimization is performed on the above model, and the optimized structure is statically self-consistent, and the unit cell volume and cohesive energy are calculated, as shown in Figure 5 and Figure 6. The calculation parameters are selected as follows: the plane wave truncation energy is greater than or equal to 500 eV, and the grid density of the Brillouin zone is greater than or equal to 9×9×5. The total energy convergence criterion of the system is less than or equal to 5×10 ^-6 eV/cell, and the single-atom force convergence criterion is less than or equal to

Calculate the inner volume and intercalation energy of the first coordination layer of any Mg atom in the Mg matrix model, and the first coordination of Zn atom in the Mg-Zn, Mg-Zn-Ca, Mg-Zn-Y, Mg-Zn-Sn solid solution models The intralayer volume and embedding energy are shown in Fig. 7 and Fig. 8.

Figures 5 to 8 show that the addition of Sn failed to transform the unit cell volume, cohesive energy, inner volume of the first coordination layer, and intercalation energy in the Mg-Zn solid solution to the Mg matrix, which is predicted to have a reduced Zn The role of solid solubility in the Mg matrix.

This prediction result is consistent with the literature (P.Ghosh et al.Critical assessment and thermodynamic modeling of Mg–Zn, Mg–Sn, Sn–Zn and Mg–Sn–Zn systems. CALPHAD, 2012, 36: 28–43) Consistently, this paper comprehensively evaluates the existing thermodynamic data of the Mg–Sn–Zn alloy system, and presents a phase diagram of the Mg–Sn–Zn alloy that is consistent with the experimental data (Fig. 12 in the literature). The solid solution phase boundary of the Mg-rich corner indicates that the solid solution of Sn in the Mg matrix leads to the decrease of Zn solid solubility at both 340 °C and 500 °C.

The control effect of Sn on the solid solubility of Zn in the Mg matrix predicted in this example is consistent with the phase diagram results, indicating that this prediction method has high accuracy in predicting the control effect of Sn on the solid solubility of Zn in Mg alloys.

Calculate the differential electron density in the ternary Mg-Zn-Ca, Mg-Zn-Y solid solution model in which the target and additive elements are the nearest neighbors to each other, as shown in Figures 9 and 10.

It can be seen from Fig. 5 to Fig. 10 that the addition of Ca makes the unit cell volume, cohesive energy, inner volume and intercalation energy of the first coordination layer in the Mg-Zn solid solution all transformed to the Mg matrix, and when Ca and Zn interact with each other. When it is the nearest neighbor atom, the aggregation of valence electrons does not occur between the two, so it is predicted to have the effect of improving the solid solubility of Zn in the Mg matrix.

This prediction result is consistent with the literature (Li Hongxiao, Ma Qianqian, Ren Yuping, et al. Mg-Zn-Ca system Mg-rich region ternary compounds and their solid-state phase equilibrium [J]. Chinese Journal of Metals, 2011(04):385-390) Consistently, the literature presents the experimentally determined phase diagram of the Mg-rich region of the Mg-Zn-Ca alloy (Fig. 6 in the literature). The phase diagram results show that the addition of Ca can increase the maximum solid solubility of Zn in the Mg matrix from 2.4% to 4.6% at 335 °C, which is nearly doubled.

The control effect of Ca on the solid solubility of Zn in the Mg matrix predicted in this example is consistent with the experimental data, indicating that this prediction method has high accuracy in predicting the control effect of Ca on the solid solubility of Zn in Mg alloys.

Although Y also changes the values of the above four parameters to the Mg matrix, when Y and Zn are the nearest neighbors to each other, significant valence electron aggregation occurs between them, which will reduce the solid solubility of Zn in the Mg matrix.

This prediction result is consistent with the literature (B.S Liu et al. Phase equilibria of low-Y side in Mg-Zn-Y system at 400℃. Rare Metal, 2020, 39(3): 262-269), which Experimentally determined values of the solid solubility of Zn and Y in the solid solution phase of Mg-Zn-Y alloys are given (Table 1 in the literature). The results show that at 400°C, when the solid solution phase does not contain Y, the measured value of the Zn solid solubility is between 2.2% and 3.2%; when the Y content in the solid solution phase is 0.2%, the Zn solid solubility fell to 0.4%.

The control effect of Y on the solid solubility of Zn in the Mg matrix predicted in this example is consistent with the experimental data, indicating that this prediction method has high accuracy in predicting the control effect of Y on the solid solubility of Zn in Mg alloys.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still understand the foregoing embodiments. The technical solutions described are modified, or some technical features thereof are equivalently replaced. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

The method for predicting the effect of adding elements on the regulation and control of the solid solubility of the target element is characterized by comprising:

Build metal matrix, binary solid solution, ternary solid solution crystal models, and single-atom models of matrix elements, target elements, and additive elements, respectively;

Through the structural optimization and static self-consistency of the first-principles calculation, the unit cell volume and cohesive energy of the above model and the inner volume and embedding energy of the first coordination layer are obtained. The ternary solid solution is selected from the target element and the added element. There is no unit cell of shared atoms in the bit layer, and the numerical evolution trend of solid solution expansion from binary to ternary caused by adding elements is analyzed.
The method for predicting the effect of an additive element on the solid solubility of a target element according to claim 1, wherein if the additive element does not cause the parameter value in the original binary solid solution to change to the metal matrix, it is predicted that the additive element has a reduced target The role of elements in the solid solubility of the matrix; if the addition of elements causes the parameter values in the original binary solid solution to change to the metal matrix, the ternary solid solution can be obtained through structural optimization and static self-consistency and non-self-consistency calculated by first-principles calculations. The differential electron density in the ternary solid solution is selected from the unit cell where the target element and the additive element are the nearest neighbors to each other, and the distribution state of valence electrons is analyzed;

Or, if there is no valence electron aggregation between the target element and the additive element in the differential electron density, it is predicted that the additive element has the effect of improving the solid solubility of the target element in the metal matrix; if the valence electron aggregation occurs, it is predicted as The added element has the effect of reducing the solid solubility of the target element in the metal matrix.
The method for predicting the effect of adding elements on the regulation and control of the solid solubility of a target element according to claim 1, wherein the metal matrix crystal model is to construct a pure metal cell according to the experimentally determined space group, lattice parameters and atomic coordinates , and expand it into a supercell, and the expansion coefficient in the direction of each basis vector must be greater than or equal to 3;

Or, the binary solid solution crystal model is to replace any atom in the pure metal supercell with the target element;

Or, the ternary solid solution crystal model is to replace the two atoms in the pure metal supercell with the target element and the additive element respectively;

Or, the ternary solid solution crystal model includes no shared atoms in the first coordination layer of the target element and the additive element, and the target element and the additive element are the nearest neighbor atoms to each other;

Or, for the single-atom model, an orthorhombic lattice needs to be constructed, and the lattice parameters meet the following conditions:

a≠b≠c, atoms can be fixed at any position in the lattice.
The method for predicting the effect of additive elements on the solid solubility regulation of target elements according to claim 1,

It is characterized in that the calculation parameters include: the plane wave truncation energy is greater than or equal to 350 eV, the grid density of the Brillouin zone is greater than or equal to 9 × 9 × 5; the total energy convergence criterion of the system is less than or equal to 5 × 10 -6 eV/cell, and the single atom is subjected to Force convergence criterion is less than or equal to
The method for predicting the effect of adding elements on the regulation of the solid solubility of a target element according to claim 1, wherein the optimized unit cell is statically self-consistent by using first-principles calculation software to obtain the metal matrix, binary And the unit cell volume and total energy of the ternary solid solution, the static self-consistency of the single-atom model is implemented, the single-atom total energy of the matrix element, the target element, and the added element is obtained, and the cohesive energy of each system is calculated.
The method for predicting the control effect of additive elements on the solid solubility of target elements according to claim 1, characterized in that, in the optimized unit cell of the metal matrix, the binary solid solution and the selected ternary solid solution, the identified The atoms in the first coordination layer are removed, and first-principles calculation software is used to implement static self-consistency to obtain the total energy of the system, and then calculate the embedded energy in the first coordination layer.
The method for predicting the control effect of additive elements on the solid solubility of a target element according to claim 1, characterized in that, by using first-principles calculation software, a static self-consistent and Not self-consistent, calculate the differential electron density.
The method for predicting the effect of an additive element on the solid solubility of a target element according to claim 1, wherein the matrix element is Mg, the target element is Zn, and the additive element is selected from Ca, Sn and Y;

Or, the method for predicting the effect of adding elements on the regulation of the solid solubility of the target element includes:

Model construction: Build Mg matrix, binary Mg-based solid solution, ternary Mg-based solid solution lattice models, and single-atom models of Mg, target elements, and added elements;

Calculation process: optimize the model, calculate the unit cell volume and total energy of Mg matrix, binary and ternary Mg-based solid solutions, and the total energy of single atoms of Mg, target elements, and additive elements, and obtain the cohesive energy of each system;

In the optimized unit cell of Mg matrix, the first coordination layer of any Mg atom was identified, and the first coordination layer of the target element in the optimized unit cell of binary and ternary Mg-based solid solution was identified respectively. The inner volume of the first coordination layer; the identified atoms in the first coordination layer are removed from the optimized unit cells of the Mg matrix, the binary Mg-based solid solution and the selected ternary Mg-based solid solution, respectively, to obtain the total system volume. energy and the intercalation energy in the first coordination layer;

According to the above four parameters, the numerical evolution trend of the Mg-based solid solution from binary expansion to ternary caused by the addition of elements is clearly defined. If the addition of elements causes the parameter values in the original binary Mg-based solid solution to change to the Mg matrix, the above The selected differential electron density of the ternary Mg-based solid solution finally achieves an effective prediction for the control effect of the added elements in the Mg alloy on the solid solubility of the target element.
Application of the method for predicting the control effect of the additive element on the solid solubility of the target element according to claim 1 in the field of alloy design.
An alloy design method capable of directional regulation of the solid solubility of a target element, characterized in that it includes the method for predicting the regulation effect of an additive element on the solid solubility of the target element according to any one of claims 1 to 8.