Molecular dynamics simulation method for tensile testing of heterogeneous composition refractory CuNb amorphous alloy

Abstract

The present invention describes a molecular dynamics simulation method for tensile testing of a refractory CuNb amorphous alloy with heterogeneous components. The specific steps are: establishing a CuNb crystal alloy model with uniform component distribution; using an EAM potential function to describe the atomic interaction between Cu and Nb; simulating the process of rapid heating and rapid cooling of the model to obtain a uniform CuNb amorphous alloy model, and outputting atomic coordinates; shearing and combining uniform amorphous alloy models with different atomic ratios to establish a series of amorphous alloy tensile models with different component distributions; performing tensile simulation on the amorphous alloy tensile model to output atomic information under different strains; visualizing the atomic information under different strains to output the deformation morphology, strain cloud map, stress cloud map and atomic cluster distribution map of the amorphous alloy tensile model under different strains; revealing the plastic deformation mechanism of the refractory CuNb amorphous alloy and the influence mechanism of component distribution on the tensile deformation of the refractory CuNb amorphous alloy.

Description

Technical Field

[0001] The present invention relates to the technical field of molecular dynamics simulation, and in particular to a molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy. Background Art

[0002] The development of modern industry requires metal materials to possess a variety of excellent properties, including high strength, high toughness, high ductility, high wear resistance, and high temperature resistance. Amorphous alloys, with their exceptional properties such as ultra-high GPa-level strength and wear resistance, hold great promise for applications in aviation, aerospace, and navigation. However, existing experimental results indicate that amorphous alloys have very low ductility, a drawback that limits their industrial applications. Uncovering the microscopic mechanisms underlying the low ductility of amorphous alloys and improving their ductility through micro- and nanostructure design have become hot research topics.

[0003] Research on the ductility of amorphous alloys is primarily based on tensile testing. Because amorphous alloys are typically obtained from molten alloys through a rapid cooling process, the sample size is relatively small, and tensile testing requires high-precision instruments and equipment. Exploring the microscopic deformation mechanisms of amorphous alloys requires characterizing their microstructure, which typically requires expensive equipment such as a TEM (transmission electron microscope) or even an HTEM (high-resolution transmission electron microscope), costing millions or even tens of millions of dollars. Even with sophisticated instruments and equipment, the structural disorder of amorphous alloys makes it difficult to obtain effective atomic information, hindering the development of the microscopic deformation mechanisms of amorphous alloys. Furthermore, the compositional distribution has a significant impact on the ductility of amorphous alloys, but the experimental preparation of amorphous alloys with specific compositional distributions presents technical difficulties. Summary of the Invention

[0004] In order to solve the problems existing in the above-mentioned prior art, the present invention provides a molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy, and its specific technical solution is as follows:

[0005] A molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy comprises the following steps:

[0006] S1: establishing multiple CuNb crystal alloy models in Atomsk software, wherein Cu atoms and Nb atoms are evenly distributed in the CuNb crystal alloy models, and the ratio of Cu atoms to Nb atoms in each CuNb crystal alloy model is different;

[0007] S2: EAM potential function is used to describe the atomic interaction between Cu and Nb;

[0008] S3: Using lammps software, the rapid heating and cooling processes of the CuNb crystal alloy model are simulated to obtain multiple CuNb amorphous alloy models and output atomic coordinates.

[0009] S4: Using the cut command of the Atomsk software, the CuNb amorphous alloy models obtained in step S3 are cut and combined to prepare a series of CuNb amorphous alloy tensile models with heterogeneous component distribution, such as gradient components;

[0010] S5: Using lammps software, perform a tensile simulation on the CuNb amorphous alloy tensile model obtained in step S4, and output atomic information under different strains;

[0011] S6: The atomic information under different strains obtained in step S5 is visualized using Ovito software to output the deformation morphology, strain cloud map, and stress cloud map of the CuNb amorphous alloy tensile model under different strains;

[0012] S7: Using the atomic information obtained in step S5, the distribution of atomic clusters in the CuNb amorphous alloy tensile model is visualized;

[0013] S8: The deformation morphology, strain cloud map, stress cloud map and cluster distribution of the CuNb amorphous alloy tensile model under different strains obtained through steps S6 and S7 reveal the plastic deformation mechanism of the refractory CuNb amorphous alloy and the influence mechanism of component distribution on the tensile deformation of the refractory CuNb amorphous alloy.

[0014] Furthermore, in step S1, the CuNb crystal alloy model is established by the following steps:

[0015] S101, construct a face-centered cubic lattice type Cu unit cell using the create command, set the lattice orientation to x=

[100] , y=

[010] , z=

[001] , and the lattice constant to 0.3615 nm.

[0016] S102 , using the Cu unit cell as the smallest unit, periodically replicates it along the x, y, and z directions using the duplicate command to obtain a single crystal Cu model.

[0017] S103, randomly selecting Cu atoms in the single crystal Cu model using the select command, and then using the substitute command to replace the selected Cu atoms with Nb atoms, thereby obtaining a CuNb crystal alloy model with a specific atomic ratio and uniform atomic distribution.

[0018] Furthermore, the size of the single crystal Cu model is set to be larger than the size of the CuNb amorphous alloy tensile model.

[0019] Furthermore, in step S3, a rapid heating and cooling process simulation of a CuNb crystal alloy model is established by the following steps:

[0020] S301, rapid heating process simulation: Set the boundary conditions in the x, y, and z directions to periodic boundary conditions, adopt the NPT ensemble, set the time step to 2 fs, and set the initial temperature of the system to 0K; use the fix command to rapidly heat the CuNb crystal alloy model to 3000K, and then relax at 3000K under the NPT ensemble for 1000 ps to obtain a steady-state CuNb amorphous alloy;

[0021] S302 , rapidly cooling the CuNb amorphous alloy to a stretching simulation temperature to obtain a CuNb amorphous alloy model with a specific composition at the stretching simulation temperature.

[0022] Furthermore, the heating rate of the rapid heating and the cooling rate of the rapid cooling are both set to 1×10^12 K / s.

[0023] Furthermore, in step S4, the shearing and assembly of the CuNb amorphous alloy model is completed by the following steps:

[0024] S401, cutting the CuNb amorphous alloy model using the cut command of the atomsk software to obtain a plurality of CuNb amorphous alloy units with the same size but different atomic ratios;

[0025] S402 , using a merge command, combining multiple CuNb amorphous alloy units with different atomic ratios in a specific order to form a series of CuNb amorphous alloy tensile models with heterogeneous components, such as gradient components.

[0026] Furthermore, before the stretching simulation, the internal stress caused by the modeling process in step S4 was relieved by a heat treatment process. Specifically, the CuNb amorphous alloy stretching model was relaxed for 200 ps in the NPT ensemble at a temperature of 400 K, then cooled to the stretching simulation temperature, and then relaxed for another 200 ps.

[0027] Furthermore, when the CuNb amorphous alloy tensile model is subjected to tensile simulation, the boundary conditions in the x and y directions are set as periodic boundary conditions, the boundary condition in the z direction is set as free boundary conditions, the tensile direction is the x direction, and the tensile rate is set to 5×10^8 s -1 , the stress in the y direction is set to zero during stretching, so that the CuNb amorphous alloy stretching model maintains a uniaxial stress state.

[0028] Furthermore, in step S7, a method for identifying atomic clusters of CuNb amorphous alloy is established, comprising the following steps:

[0029] S701, define the cutoff radius cutoff in OVITO software;

[0030] S702, calling the built-in function CutoffNeighborFinder of the OVITO software, constructing a neighbor atom list for each atom in the CuNb amorphous alloy tensile model according to the cutoff radius set in step S701, and creating a new one-dimensional array Cu_Nb_rich. If the atom belongs to a Cu-rich cluster, it is represented by 1, if it belongs to a Nb-rich cluster, it is represented by 2, and other clusters are represented by 0;

[0031] S703, through a for loop, traverse all atoms and count the number of Cu atoms (Cu_number), the number of Nb atoms (Nb_number), and the total number of neighbors (neigh_number) in all neighbor atom lists. Then calculate the ratio of Cu atoms (Cu_ratio) and the ratio of Nb atoms (Nb_ratio) within the cutoff radius of the atom. If the ratio of Cu atoms exceeds 60%, the atom belongs to a Cu-rich cluster. If the ratio of Cu atoms is less than 40%, the atom belongs to a Nb-rich cluster. Other ratios belong to other clusters. According to the type of cluster to which the atom belongs, the information is added to the one-dimensional array Cu_Nb_rich defined in S702;

[0032] S704 , calling the OVITO library function create_user_particle_property, mapping the calculated one-dimensional array Cu_Nb_rich result to each atom one by one, and using the color command to color the atoms according to the cluster type, completing the identification and visualization process of atomic clusters in the refractory CuNb amorphous alloy.

[0033] Based on the above technical solution, the present invention has the following beneficial effects:

[0034] 1. This paper uses molecular dynamics to simulate the tensile process of heterogeneous amorphous alloys, exploring the microscopic deformation mechanism of amorphous alloys and the influence of component distribution on their ductility. Furthermore, the molecular dynamics tensile simulation process can output a variety of effective information, such as atomic positions, atomic stresses, and atomic strains. Based on this atomic information, the microstructure of the amorphous alloy can be effectively characterized, revealing its deformation mechanism.

[0035] 2. The cluster analysis method described in the present invention is based on the structural characteristics of atomic clusters in refractory amorphous alloys, can identify atomic clusters with different atomic contents, and can further reveal the deformation mechanism of refractory amorphous alloys from the perspective of atomic clusters.

[0036] 3. The modeling method of the heterogeneous component CuNb amorphous alloy, the tensile simulation method of the CuNb amorphous alloy, and the analysis method for the cluster structure of the refractory CuNb amorphous alloy provided by the present invention can predict the influence mechanism of different component distributions on the ductility of the refractory CuNb amorphous alloy through simulation, provide a reference for the experimental study of the microscopic mechanism of amorphous alloys, effectively reduce experimental costs, and provide more atomic information than experimental observations. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 : Cu 40 Nb 60 Schematic diagram of the CuNb crystal alloy model as an example;

[0038] Figure 2 : Cu 40 Nb 60 Schematic diagram of the CuNb amorphous alloy model as an example;

[0039] Figure 3 : Schematic diagram of the CuNb amorphous alloy model with gradient composition distribution after shearing and assembly;

[0040] Figure 4 : Cu 40 Nb 60 Schematic diagram of the morphology of a CuNb amorphous alloy model with uniform composition after uniaxial stretching;

[0041] Figure 5 : Cu 40 Nb 60 Schematic diagram of the strain cloud of a CuNb amorphous alloy model with uniform composition after uniaxial stretching;

[0042] Figure 6 : Cu 40 Nb 60 Schematic diagram of cluster distribution of a CuNb amorphous alloy model with uniform composition after uniaxial stretching. DETAILED DESCRIPTION

[0043] It should be noted that:

[0044] 1. Certain terms are used in the specification and claims to refer to specific components or structures. Those skilled in the art will understand that they may use different terms to refer to the same component or structure. This specification and claims do not distinguish components or structures based on differences in terms, but rather on differences in their functions.

[0045] 2. Unless otherwise defined, technical or scientific terms used in the present disclosure should have the same meaning as commonly understood by persons having ordinary skills in the field to which the present disclosure belongs.

[0046] The following is combined with Figure 1 -Attached Figure 6 , the present invention is described in detail by way of embodiments.

[0047] This embodiment describes a molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy, which specifically includes the following steps.

[0048] S1: Create a crystal structure model of CuNb alloy in Atomsk software. The steps are as follows:

[0049] S101, construct a face-centered cubic lattice type Cu unit cell using the create command, set the lattice orientation to x=

[100] , y=

[010] , z=

[001] , and the lattice constant to 0.3615 nm.

[0050] S102 , using the Cu unit cell as the smallest unit, periodically replicates it along the x, y, and z directions using the duplicate command to obtain a single crystal Cu model.

[0051] Here, if the size of the single crystal Cu model is small, the size of the subsequently obtained amorphous model will be small. When establishing the amorphous stretching model, the smaller amorphous model needs to be periodically expanded, resulting in the structural periodicity of the stretching model, which is inconsistent with the actual situation. The model size should be increased as much as possible while considering the amount of calculation. Therefore, setting the size of the single crystal Cu model larger than the final stretching model size can ensure that the final stretching model is obtained by shearing the amorphous model, avoiding the structural periodicity problem mentioned above.

[0052] S103 , randomly selecting Cu atoms in the single crystal Cu model using the select command, and then using the substitute command to replace the selected Cu atoms with Nb atoms, thereby obtaining a CuNb crystal structure model with a specific atomic ratio, namely, a CuNb crystal alloy model.

[0053] In the CuNb crystal alloy model, Cu atoms and Nb atoms are evenly distributed, and the ratio of Cu atoms to Nb atoms in each CuNb crystal alloy model is different. For example, Cu 40 Nb 60 , Cu 50 Nb 50 , Cu 60 Nb 40 wait.

[0054] Here, a random selection command is set to obtain a CuNb crystal structure with a specific atomic ratio. This ensures a uniform distribution of atoms in the model and similar components throughout the model, making the subsequently obtained amorphous model a uniform model without significant compositional changes.

[0055] S2: The embedded atom potential (EAM) function is used to describe the atomic interaction between Cu and Nb in the subsequently prepared CuNb amorphous alloy.

[0056] This example simulates a metal system, so the embedded atom potential (EAM) developed by Daw and Baskes is used to describe the atomic interactions between Cu and Nb. The specific parameters can preferably be adopted from the parameters in the paper "Liquid-phase thermodynamics and structures in the Cu–Nb binary system" by Zhang et al. Their research results show that the EAM potential function under these parameters can accurately describe the structural characteristics of atomic clusters in refractory CuNb amorphous alloys. They will not be repeated here.

[0057] S3: Using the lammps software, the rapid heating and cooling processes of the CuNb crystal alloy model are simulated to obtain the CuNb amorphous alloy model and output the atomic coordinates.

[0058] Here are the steps:

[0059] S301, rapid heating process simulation:

[0060] The boundary conditions in the x, y, and z directions are all set to periodic boundary conditions, using the NPT ensemble, with a time step of 2 fs and an initial temperature of 0 K.

[0061] The CuNb crystal alloy model was rapidly heated to 3000K at a rate of 1×10^12 K / s using the fix command, and then isothermally relaxed for 1000 ps at 3000K under the NPT ensemble to obtain a steady-state CuNb amorphous alloy.

[0062] S302 , rapidly cooling the CuNb amorphous alloy to a stretching simulation temperature to obtain a CuNb amorphous alloy model with a specific composition at the stretching simulation temperature.

[0063] To ensure that the CuNb amorphous alloy does not have time to crystallize during the cooling process, the cooling rate of the cooling process should be large enough. Therefore, the cooling rate in this step is set to 1×10^12 K / s.

[0064] S303, outputting the atomic position file through the dump command.

[0065] In the above steps,

[0066] a. Set the boundary conditions in the x, y, and z directions to periodic boundary conditions to avoid boundary effects;

[0067] b. The stretching simulation temperature is set to 300K.

[0068] S4: After obtaining uniform CuNb amorphous alloy models with different atomic proportions in step S3, the obtained uniform composition CuNb amorphous alloy models with different atomic proportions are cut and combined using the cut command in the Atomsk software to prepare a series of CuNb amorphous alloy tensile models with heterogeneous compositions, such as gradient compositions. Heterogeneous compositions refer to the non-uniform distribution of components in the amorphous alloy, and their distribution characteristics include, but are not limited to, gradient distribution and bimodality.

[0069] Here are the steps:

[0070] S401, using the cut command of the Atomsk software, shearing the uniform composition CuNb amorphous alloy model with different atomic proportions to obtain a plurality of uniform composition CuNb amorphous alloy units with the same size but different atomic proportions;

[0071] S402: Using the merge command, multiple CuNb amorphous alloy units with uniform composition and different atomic proportions are combined in a specific order to form a series of CuNb amorphous alloy tensile models with specific composition distributions, such as a CuNb amorphous alloy tensile model with a bimodal composition distribution or a CuNb amorphous alloy tensile model with a gradient composition distribution.

[0072] S5: Using lammps software, perform a tensile simulation on the CuNb amorphous alloy tensile model obtained in step S4, and output atomic information under different strains, including but not limited to overall stress, atomic position, atomic stress, atomic number, atomic mass, atomic energy, and other information under the current strain.

[0073] In this step,

[0074] a. Use EAM potential function to describe the interaction between Cu and Nb atoms;

[0075] b. Before the stretching simulation, the system was subjected to a heat treatment process to relieve the internal stress caused by the modeling process in step S4. Specifically, the CuNb amorphous alloy stretching model was relaxed for 200 ps in the NPT ensemble at 400 K, then cooled to the stretching simulation temperature, and then relaxed for another 200 ps to allow the CuNb amorphous alloy stretching model to reach a steady state;

[0076] c. During the stretching simulation, the boundary conditions in the x and y directions were set to periodic boundary conditions, the boundary condition in the z direction was set to free boundary conditions, and the stretching direction was the x direction. This setting ensured that the CuNb amorphous alloy stretching model would shrink at the free boundaries during the stretching process, which is consistent with the shear and necking phenomena observed in the experiment.

[0077] d. Use the fix deform command to stretch the CuNb amorphous alloy model along the x-axis in the NPT ensemble and at the stretching temperature. The stretching rate is set to 5×10^8 s. -1 , set the stress in the y direction to zero during stretching to keep the model in a uniaxial stress state;

[0078] e. During the stretching simulation, the dump command is used to output the atomic information under the current strain every 2000 steps.

[0079] S6: The atomic information under different strains obtained in step S5 is visualized using Ovito software to output the deformation morphology, strain cloud map, and stress cloud map of the CuNb amorphous alloy tensile model under different strains.

[0080] In this step:

[0081] According to 5×10^8 s -1 The tensile rate and output time step of 2000 fs indicate that atomic information is output every 0.001 strain during the tensile simulation. Based on the atomic positions at a given strain, the Ovito software outputs the morphology of the CuNb amorphous alloy tensile model at that strain.

[0082] The atomic strain command can be used to calculate the von Mises strain of an atom based on the atomic positions under different strains of the same atom.

[0083] Based on the atomic stress, the stress cloud diagram under the strain can be output.

[0084] In summary, the tensile deformation morphology of the CuNb amorphous alloy tensile model, the strain cloud map under different strains, and the stress cloud map can be obtained.

[0085] S7: Refractory CuNb amorphous alloys exhibit the structural characteristics of atomic clusters. Based on the proportion of surrounding atoms, atoms are classified as Cu-rich clusters, Nb-rich clusters, and other clusters. Cu atoms with a proportion of 60% or more are considered Cu-rich clusters, while those with a proportion of less than 40% are considered Nb-rich clusters. Clusters with other proportions are considered other clusters. Identifying and distinguishing between these clusters is crucial for analyzing the deformation behavior of refractory CuNb amorphous alloys.

[0086] Based on the atomic information obtained in step S5, an atomic cluster identification method for a CuNb amorphous alloy tensile model is established, comprising the following steps:

[0087] S701, define the cutoff radius in the OVITO software. The cutoff radius is usually selected by selecting the horizontal coordinate corresponding to the second peak of the RDF curve of the CuNb amorphous alloy tensile model, so that the second-nearest neighbor atoms of the atom can be taken into account.

[0088] In step S702, the CutoffNeighborFinder function of the OVITO software is called to construct a neighbor atom list for each atom in the CuNb amorphous alloy tensile model according to the cutoff radius set in step S701. A new one-dimensional array Cu_Nb_rich is created. If the atom belongs to a Cu-rich cluster, it is represented by 1; if it belongs to a Nb-rich cluster, it is represented by 2; other clusters are represented by 0.

[0089] In step S703, a for loop is used to iterate over all atoms, counting the number of Cu atoms (Cu_number), the number of Nb atoms (Nb_number), and the total number of neighbors (neigh_number) within the neighbor atom list. The Cu ratio (Cu_ratio) and the Nb ratio (Nb_ratio) within the cutoff radius of the atom are then calculated. If the Cu ratio exceeds 60%, the atom belongs to a Cu-rich cluster. If the Cu ratio is less than 40%, the atom belongs to a Nb-rich cluster. Other ratios belong to other clusters. Based on the cluster type to which the atom belongs, this information is added to the one-dimensional array Cu_Nb_rich defined in step S702.

[0090] S704 , calling the OVITO library function create_user_particle_property, mapping the calculated one-dimensional array Cu_Nb_rich result to each atom one by one, and using the color command to color the atoms according to the cluster type, completing the identification and visualization process of atomic clusters in the refractory CuNb amorphous alloy.

[0091] S8: Based on the stress-strain curves, deformation process, atomic strain cloud map, stress cloud map, cluster distribution and other information under different strains of the CuNb amorphous alloy tensile model obtained in step S6 and step S7, the plastic deformation mechanism of the refractory CuNb amorphous alloy and the influence mechanism of component distribution on the tensile deformation of the refractory CuNb amorphous alloy can be analyzed.

[0092] The basic principles, main features, and advantages of the present invention are shown and described above. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are merely illustrative of the principles of the present invention. Various changes and modifications may be made to the present invention without departing from the spirit and scope of the present invention, and such changes and modifications fall within the scope of the invention as claimed.

Claims

1. A molecular dynamics simulation method for tensile testing of heterogeneous component refractory CuNb amorphous alloys, characterized in that: The following steps are involved: S1: establishing multiple CuNb crystal alloy models in Atomsk software, wherein Cu atoms and Nb atoms are evenly distributed in the CuNb crystal alloy models, and the ratio of Cu atoms to Nb atoms in each CuNb crystal alloy model is different; S2: EAM potential function is used to describe the atomic interaction between Cu and Nb; S3: Using lammps software, the rapid heating and cooling processes of the CuNb crystal alloy model were simulated to obtain multiple CuNb amorphous alloy models with different atomic proportions and output the atomic coordinates. S4: Using the cut command of the Atomsk software, multiple CuNb amorphous alloy models with different atomic ratios obtained in step S3 are cut and combined to prepare a series of CuNb amorphous alloy tensile models with heterogeneous components; S5: Using lammps software, perform a tensile simulation on the CuNb amorphous alloy tensile model obtained in step S4, and output atomic information under different strains; S6: The atomic information under different strains obtained in step S5 is visualized using Ovito software to output the deformation morphology, strain cloud map, and stress cloud map of the CuNb amorphous alloy tensile model under different strains; S7: Using the atomic information obtained in step S5, the distribution of atomic clusters in the CuNb amorphous alloy tensile model is visualized; S8: The deformation morphology, strain cloud map, stress cloud map and cluster distribution of the CuNb amorphous alloy tensile model under different strains obtained through steps S6 and S7 reveal the plastic deformation mechanism of the refractory CuNb amorphous alloy and the influence mechanism of component distribution on the tensile deformation of the refractory CuNb amorphous alloy.

2. The molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy according to claim 1, characterized in that: In step S1, the CuNb crystal alloy model is established by the following steps: S101, construct a face-centered cubic Cu unit cell using the create command, set the lattice orientation to x=[100], y=[010], z=[001], and the lattice constant to 0.3615 nm; S102, using the Cu unit cell as the smallest unit, periodically replicate it along the x, y, and z directions using the duplicate command to obtain a single crystal Cu model; S103, randomly selecting Cu atoms in the single crystal Cu model using the select command, and then using the substitute command to replace the selected Cu atoms with Nb atoms, thereby obtaining a CuNb crystal alloy model with a specific atomic ratio and uniform atomic distribution.

3. The molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy according to claim 2, characterized in that: The size of the single crystal Cu model is set to be larger than that of the CuNb amorphous alloy tensile model.

4. The molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy according to claim 1, characterized in that: In step S3, a rapid heating and cooling process simulation of a CuNb crystal alloy model is established by the following steps: S301, rapid heating process simulation: Set the boundary conditions in the x, y, and z directions to periodic boundary conditions, adopt the NPT ensemble, set the time step to 2 fs, and set the initial temperature of the system to 0K; use the fix command to rapidly heat the CuNb crystal alloy model to 3000K, and then relax at 3000K under the NPT ensemble for 1000 ps to obtain a steady-state CuNb amorphous alloy; S302 , rapidly cooling the CuNb amorphous alloy to a stretching simulation temperature to obtain a CuNb amorphous alloy model with a specific composition at the stretching simulation temperature.

5. The molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy according to claim 4, characterized in that: The heating rate for rapid heating and the cooling rate for rapid cooling were both set to 1×10^12 K / s.

6. The molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy according to claim 1, characterized in that: In step S4, the shearing and assembly of the CuNb amorphous alloy model is completed by the following steps: S401, cutting the CuNb amorphous alloy model using the cut command of the atomsk software to obtain a plurality of CuNb amorphous alloy units with the same size but different atomic ratios; S402 , using the merge command, combining multiple CuNb amorphous alloy units with different atomic ratios in a specific order to form a series of CuNb amorphous alloy tensile models with heterogeneous component distributions.

7. The molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy according to claim 1, characterized in that: Before the stretching simulation, the internal stress caused by the modeling process in step S4 was relieved by a heat treatment process. Specifically, the CuNb amorphous alloy stretching model was relaxed for 200 ps in the NPT ensemble at 400 K, then cooled to the stretching simulation temperature, and then relaxed for another 200 ps.

8. The molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy according to claim 1, characterized in that: When performing tensile simulation on the CuNb amorphous alloy tensile model, the boundary conditions in the x and y directions are set to periodic boundary conditions, the boundary condition in the z direction is set to free boundary conditions, the tensile direction is the x direction, and the tensile rate is set to 5×10^8 s -1 , the stress in the y direction is set to zero during stretching, so that the CuNb amorphous alloy stretching model maintains a uniaxial stress state.

9. The molecular dynamics simulation method for tensile testing of a heterogeneous component refractory CuNb amorphous alloy according to claim 1, characterized in that: In step S7, a method for identifying atomic clusters of CuNb amorphous alloy is established, comprising the following steps: S701, define the cutoff radius cutoff in OVITO software; S702, calling the built-in function CutoffNeighborFinder of the OVITO software, constructing a neighbor atom list for each atom in the CuNb amorphous alloy tensile model according to the cutoff radius set in step S701, and creating a new one-dimensional array Cu_Nb_rich. If the atom belongs to a Cu-rich cluster, it is represented by 1, if it belongs to a Nb-rich cluster, it is represented by 2, and other clusters are represented by 0; S703, through a for loop, traverse all atoms and count the number of Cu atoms (Cu_number), the number of Nb atoms (Nb_number), and the total number of neighbors (neigh_number) in all neighbor atom lists; then calculate the ratio of Cu atoms (Cu_ratio) and the ratio of Nb atoms (Nb_ratio) within the cutoff radius of the atom; if the ratio of Cu atoms exceeds 60%, the atom belongs to a Cu-rich cluster; if the ratio of Cu atoms is less than 40%, the atom belongs to a Nb-rich cluster; other ratios belong to other clusters; according to the type of cluster to which the atom belongs, the information is added to the one-dimensional array Cu_Nb_rich defined in S702; S704 , calling the OVITO library function create_user_particle_property, mapping the calculated one-dimensional array Cu_Nb_rich result to each atom one by one, and using the color command to color the atoms according to the cluster type, completing the identification and visualization process of atomic clusters in the refractory CuNb amorphous alloy.

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