Method for constructing helium bubbles in alloy

Abstract

The invention discloses a method for constructing helium bubbles in an alloy. The method comprises the following steps: 1, constructing FCC (Fluid Catalytic Cracking) structure unit cells; 2, constructing a simulated crystal structure; 3, constructing a high-entropy alloy structure; and fourthly, the high-entropy alloy structure is filled with He atoms, and He bubbles are formed. According to the method, a reasonable helium bubble radius structure is embedded into the high-entropy alloy through molecular dynamics, the He cluster formation details in the high-entropy alloy are researched, the method is a starting end for researching the dynamic process details of the He cluster in the high-entropy alloy, and the method has great theoretical guiding significance in nuclear reactors and future magnetic fusion reactor environments.

Description

Technical Field

[0001] The invention belongs to the technical field of molecular dynamics, and in particular relates to a method for constructing helium bubbles in an alloy. Background Art

[0002] High entropy alloys (HEAs) are considered to be promising structural materials for fusion and fourth-generation fission reactors. Among them, FeNiCrCoCu high entropy alloy is one of the candidate materials with application value due to its good mechanical properties at high temperature (1273K), excellent corrosion resistance, and strong radiation resistance under heavy ion implantation. In addition, helium (He) bombardment will lead to the evolution of metal microstructure. Due to the extremely low solubility of helium gas, it tends to form clusters in solids rather than stay in the body as isolated interstitial atoms. When more helium is injected into the material, He bubbles will form in the metal body, which will seriously change the retention of fusion reactor hydrogen isotopes in the material and the sputtering behavior of the wall material, thereby affecting the normal reaction operation of the core plasma. Therefore, studying the evolution of He bubbles in high entropy alloys and their influence on the surface morphology has become the key to understanding the deterioration of the surface performance of plasma-facing materials. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a method for constructing helium bubbles in an alloy in view of the deficiencies in the above-mentioned prior art, to construct a reasonable helium bubble radius structure embedded in a high entropy alloy through molecular dynamics, and to study the formation details of He clusters in the high entropy alloy. This is the beginning of studying the details of the dynamic process of He clusters in high entropy alloys, and has important theoretical guiding significance in the environment of nuclear reactors and future magnetic fusion reactors.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a method for constructing helium bubbles in an alloy, characterized in that the method comprises the following steps:

[0005] Step 1: construct the FCC structure unit cell;

[0006] Step 2: construct a simulated crystal structure;

[0007] Step 3: constructing a high entropy alloy structure;

[0008] Step 4: Fill He atoms into the high entropy alloy structure to form He bubbles.

[0009] The above-mentioned method for constructing helium bubbles in an alloy is characterized in that: in step 1, the crystal orientation of the constructed FCC structure unit cell is X=

[110] , Y=[-111], Z=[1-12]; wherein the direction of X is the direction of the Burger vector b, and the direction of Y is perpendicular to the slip plane.

[0010] The above-mentioned method for constructing helium bubbles in an alloy is characterized in that: in step 2, the simulated crystal structure is composed of a plurality of FCC structure cells constructed in step 1; the simulated crystal structure is a crystal structure in which 25 FCC structure cells are repeated in the X-axis direction, 20 FCC structure cells are repeated in the Y-axis direction, and 20 FCC structure cells are repeated in the Z-axis direction.

[0011] The above-mentioned method for constructing helium bubbles in an alloy is characterized in that: in step three, the metal elements constituting the high entropy alloy are used to randomly and evenly replace the atoms in the simulated crystal structure to obtain a high entropy alloy with an FCC structure.

[0012] The above-mentioned method for constructing helium bubbles in an alloy is characterized in that: in step four, the position and radius of the He bubble to be filled are determined in the high entropy alloy structure constructed in step three, and then a spherical structure of equal volume is hollowed out in the high entropy alloy structure, and He atoms are filled in the spherical structure to form a He bubble.

[0013] The beneficial effect of the present invention is to construct a reasonable helium bubble radius structure embedded in a high entropy alloy through molecular dynamics, and to study the details of the formation of He clusters in the high entropy alloy. This is the beginning of studying the details of the dynamic process of He clusters in high entropy alloys, and has important theoretical guiding significance in the nuclear reactor and future magnetic fusion reactor environments.

[0014] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The figure is a flowchart of the method of the present invention.

[0016] Figure 2 It is a schematic diagram of the structure of the high entropy alloy FeNiCrCoCu containing helium bubbles of the present invention. DETAILED DESCRIPTION

[0017] like Figure 1 and Figure 2 A method for constructing helium bubbles in an alloy, the method comprising the following steps:

[0018] Step 1: construct the FCC structure unit cell;

[0019] Step 2: construct a simulated crystal structure;

[0020] Step 3: constructing a high entropy alloy structure;

[0021] Step 4: Fill He atoms into the high entropy alloy structure to form He bubbles.

[0022] The present invention constructs a reasonable helium bubble radius structure embedded in a high entropy alloy through molecular dynamics to study the details of He cluster formation in the high entropy alloy. This is the beginning of studying the details of the dynamic process of He clusters in high entropy alloys and has important theoretical guiding significance in the nuclear reactor and future magnetic fusion reactor environments.

[0023] In step 2, by repeating in the X, Y and Z directions and obtaining a three-dimensional structure of a metal crystal, 25 units are repeated in the X-axis direction, 20 units are repeated in the Y-axis direction, and 20 units are repeated in the Z-axis direction to form The size of this three-dimensional structure is determined by the units repeated in the X, Y, and Z directions. By constructing a simulated crystal structure with FCC structure units repeated in the X, Y, and Z directions, it is convenient to observe the movement trajectory of atoms in a vacuum during the He bubble bursting process.

[0024] In step three, the high entropy alloy selected is FeNiCrCoCu, and the five elements Fe, Ni, Cr, Co and Cu are used to randomly and evenly replace the atoms in the constructed FCC structure to obtain the high entropy alloy FeNiCrCoCu with FCC structure.

[0025] In step 4, assuming that other external conditions remain unchanged, the influence of He bubbles on the morphology of FeNiCrCoCu high entropy alloy is studied through the position, size and vacancy ratio of He bubbles; when constructing He bubbles in the high entropy alloy structure, one of the three conditions is used as a variable to study the influence on the morphology of high entropy alloy; taking the high entropy alloy FeNiCrCoCu as an example, the position of He bubbles is determined to be (52, 56, 83), and the position away from the substrate surface is The radius is (The size of the He bubble depends on the radius), a total of 457 atoms are taken out, and if He / vacancy = 2 is selected, 914 He atoms are filled. Whether the He bubble breaks near the substrate surface depends on the He / vacancy ratio.

[0026] In this embodiment, in step 1, the crystal orientation of the constructed FCC structure unit cell is X=

[110] , Y=[-111], Z=[1-12]; wherein the direction of X is the direction of the Burger vector b, and the direction of Y is perpendicular to the slip plane.

[0027] In actual use, when determining the crystal orientation of the constructed FCC structure unit cell, any three mutually perpendicular directions may be selected.

[0028] In this embodiment, in step 2, the simulated crystal structure is composed of a plurality of FCC structure cells constructed in step 1; the simulated crystal structure is a crystal structure in which 25 FCC structure cells are repeated in the X-axis direction, 20 FCC structure cells are repeated in the Y-axis direction, and 20 FCC structure cells are repeated in the Z-axis direction.

[0029] In this embodiment, in step three, the metal elements constituting the high entropy alloy are used to randomly and evenly replace the atoms in the simulated crystal structure to obtain a high entropy alloy with an FCC structure.

[0030] In this embodiment, in step four, the position and radius of the He bubble to be filled are determined in the high entropy alloy structure constructed in step three, and then a spherical structure of equal volume is hollowed out in the high entropy alloy structure, and He atoms are filled in the spherical structure to form a He bubble.

[0031] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent structural change made to the above embodiment based on the technical essence of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for constructing helium bubbles in an alloy, characterized in that: The method comprises the following steps: Step 1: construct the FCC structure unit cell; Step 2: construct a simulated crystal structure; Step 3: constructing a high entropy alloy structure; Step 4: Fill He atoms into the high entropy alloy structure to form He bubbles.

2. A method for constructing helium bubbles in an alloy according to claim 1, characterized in that: In step 1, the crystal orientation of the constructed FCC structure unit cell is X=[110], Y=[-111], Z=[1-12]; wherein the direction of X is the direction of the Burger vector b, and the direction of Y is perpendicular to the slip plane.

3. A method for constructing helium bubbles in an alloy according to claim 1, characterized in that: In step 2, the simulated crystal structure is composed of a plurality of FCC structure cells constructed in step 1; the simulated crystal structure is a crystal structure in which 25 FCC structure cells are repeated in the X-axis direction, 20 FCC structure cells are repeated in the Y-axis direction, and 20 FCC structure cells are repeated in the Z-axis direction.

4. A method for constructing helium bubbles in an alloy according to claim 1, characterized in that: In step three, the metal elements constituting the high entropy alloy are used to randomly and evenly replace the atoms in the simulated crystal structure to obtain a high entropy alloy with an FCC structure.

5. A method for constructing helium bubbles in an alloy according to claim 1, characterized in that: In step 4, the position and radius of the He bubble to be filled are determined in the high entropy alloy structure constructed in step 3, and then a spherical structure of equal volume is hollowed out in the high entropy alloy structure, and He atoms are filled in the spherical structure to form a He bubble.

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