Helium bubble induced numerical simulation method and system for performance degradation of material of key component of inspection and maintenance robot

Abstract

The invention discloses a helium-bubble-induced numerical simulation method and system for performance degradation of a critical component material of an inspection and maintenance robot, and relates to the technical field of numerical simulation. Firstly, experimental data of the critical component material in a nuclear radiation environment are collected and analyzed, and an SRIM / TRIM simulation model is utilized to quantify initial conditions of irradiation damage; the method comprises the following steps of: firstly, acquiring key data, then simulating an atomic scale related process by means of LAMMPS molecular dynamics to obtain key data, then performing data conversion in Python to obtain equivalent porosity, and finally researching a material performance degradation rule through ABAQUS. Influences of various factors of helium bubbles on the material performance are comprehensively considered, and accurate prediction is achieved; through numerical simulation, the performance degradation condition of the material under different helium bubble sizes, numbers and dosage rates can be rapidly evaluated, and the evaluation efficiency is greatly improved. Meanwhile, the accuracy of a numerical simulation result is ensured through experimental verification, so that an evaluation result is more reliable.

Description

Technical Field

[0001] The present invention relates to the technical field of numerical simulation, and more particularly to a method and system for numerically simulating the material performance degradation of key components of an inspection and maintenance robot induced by helium bubbles. Background Art

[0002] Currently, helium bubble formation is a critical issue in the field of inspection and maintenance robots that cannot be ignored. This issue affects the robot's performance and, more directly, its safety and service life. Helium bubble formation primarily stems from the accumulation and evolution of helium within the material. During robot operation, helium bubbles may gradually form within the material due to factors such as material stress, temperature, and magnetic fields. The presence of these bubbles disrupts the material's continuity and can cause changes in its properties, thereby affecting the robot's normal operation. Key components such as structural parts and transmission parts play a vital role in robots. These components significantly impact the robot's structural stability, motion accuracy, and lifespan. Damage to these critical components due to helium bubble formation directly impacts the robot's overall performance.

[0003] The complexity of helium bubble generation lies in the fact that its formation, growth, and coalescence are influenced by a variety of factors. These factors, including material type, operating environment, and stress state, contribute to the significant complexity of the issue. To effectively address this issue, it is necessary to address multiple aspects, including material selection, structural design, and manufacturing processes, to improve the robot's resistance to helium bubbles.

[0004] Currently, the evaluation of helium bubble-induced material degradation relies primarily on experimental testing. However, this approach has significant limitations. First, experimental testing is time-consuming and expensive. Conducting comprehensive experimental testing requires significant time and resources, which undoubtedly increases the cost and difficulty of evaluation. Second, experimental test results are often affected by various factors, such as uneven sample preparation and variations in test conditions, which can make it difficult to guarantee the accuracy and reliability of test results.

[0005] Therefore, how to develop an efficient and accurate numerical simulation and evaluation method to effectively predict and evaluate the impact of helium bubbles on material properties is an urgent problem that technicians in this field need to solve. Summary of the Invention

[0006] In view of this, the present invention provides a method and system for numerical simulation of helium bubble-induced material performance degradation of key components of inspection and maintenance robots. The method comprehensively considers the influence of helium bubble size, number and dose rate on material properties, and achieves accurate prediction and comprehensive evaluation of material performance degradation by combining multi-scale numerical simulation with experimental verification.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A numerical simulation method for the degradation of the material properties of key components of a helium bubble-induced inspection and maintenance robot, comprising:

[0009] S1. Collect and analyze the experimental data of the materials of the key components of the inspection and maintenance robot in the nuclear radiation environment;

[0010] S2. Based on the simulation model of SRIM / TRIM, calculate the number of vacancies generated by each helium ion and the displacement damage dose rate, and quantify the initial conditions of the irradiation damage;

[0011] S3. Based on the obtained experimental data and initial conditions, use LAMMPS molecular dynamics to simulate the diffusion of helium atoms, the formation of helium-vacancy clusters and the interaction with dislocations at the atomic scale, and obtain the cluster size distribution and the helium diffusion coefficient;

[0012] S4. In Python, input the helium diffusion coefficient and cluster size distribution parameters obtained at the atomic scale and set the free energy functional parameters to obtain the equivalent porosity of the helium bubbles;

[0013] S5. Based on ABAQUS, study the law of material property degradation. By inputting the constitutive model of the material and the equivalent porosity of the helium bubbles, obtain the law of mechanical property degradation.

[0014] Optionally, the experimental data includes the basic physical property parameters of the key component materials, the thermodynamic database of the W alloy, and the extracted defect characteristics; among them, the basic physical property parameters specifically include density, elastic modulus, yield strength, tensile strength, and elongation; the extracted defect characteristics include the initial dislocation density obtained by TEM.

[0015] Optionally, the S2 specifically includes:

[0016] a) SRIM / TRIM modeling:

[0017] Input the proportion of alloying elements;

[0018] Set the incident energy gradient;

[0019] The number of Monte Carlo simulations ≥ 10,000 times;

[0020] b) Output key parameters: the peak depth of helium concentration; the vacancy generation rate; the displacement damage dose rate.

[0021] Optionally, the equation for the displacement damage dose rate is:

[0022]

[0023] Among them, I is the beam current intensity, with the unit of A; q is the electric charge of each helium ion; A is the irradiation area, with the unit of cm 2 ; N d — The number of displaced atoms generated by each helium ion; N atom — The atomic density of the material, with the unit of atoms / cm 3 .

[0024] Optionally, the S3 specifically includes:

[0025] a) LAMMPS modeling:

[0026] Construct a 3D model with dimensions of 50×50×50 nm 3 , and the number of atoms ≥ 3×10 6 ;

[0027] Use the MEAM potential function to describe the many-body interaction of W-He;

[0028] Set the temperature field to 300 - 2000 K, with a gradient of 10 K / ps;

[0029] b) Key process simulation: Helium diffusion trajectory tracking; Calculation of the interaction energy of dislocation loops; Output the histogram of the cluster size distribution, and then obtain the cluster size distribution and the helium diffusion coefficient.

[0030] Optionally, the S4 specifically includes:

[0031] Python data conversion:

[0032] a) Read the MSD data and cluster distribution output by LAMMPS

[0033] b) Calculate the equivalent porosity: f = 4πR 3 ρ / 3

[0034] c) Generate an ABAQUS input file

[0035] d) Output key parameters: The average radius of helium bubbles R ∈ [1, 50] nm, number density.

[0036] Optionally, the S4 specifically includes:

[0037] Implement cross-scale damage prediction in ABAQUS:

[0038] Convert the average radius and number density of helium bubbles output by the mesoscopic model into the porosity variable of the GTN constitutive model;

[0039] Construct a three-dimensional solid model, apply the actual working condition load, and the multiaxial stress ratio is 0.5 - 1.2;

[0040] Obtain the performance degradation law through parametric scanning: the attenuation rate of elastic modulus reaches 20 - 35%, and when the helium bubble density > 1×10 23 m -3 , the fatigue crack growth rate increases by 2 - 3 orders of magnitude.

[0041] A numerical simulation system for the performance degradation of key components of an inspection, repair, and maintenance robot induced by helium bubbles, comprising:

[0042] S1. Collect and analyze the experimental data of the key component materials of the inspection, repair, and maintenance robot in the nuclear radiation environment;

[0043] S2. Based on the simulation model of SRIM / TRIM, calculate the number of vacancies and the displacement damage dose rate generated by each helium ion, and quantify the initial conditions of radiation damage;

[0044] S3. Based on the obtained experimental data and initial conditions, use LAMMPS molecular dynamics to simulate the diffusion of helium atoms, the formation of helium-vacancy clusters, and the interaction with dislocations at the atomic scale, and obtain the cluster size distribution and helium diffusion coefficient;

[0045] S4. In Python, input the helium diffusion coefficient and cluster size distribution parameters obtained at the atomic scale and set the free energy functional parameters to obtain the equivalent porosity of helium bubbles;

[0046] S5. Based on ABAQUS, conduct research on the material performance degradation law. By inputting the constitutive model of the material and the equivalent porosity of helium bubbles, obtain the mechanical property degradation law.

[0047] It can be seen from the above technical solutions that, compared with the prior art, the present invention discloses a numerical simulation method and system for the performance degradation of key components of an inspection, repair, and maintenance robot induced by helium bubbles. Through numerical simulation, it is possible to comprehensively consider the effects of helium bubble size, number, and dose rate on the performance of key components of the inspection, repair, and maintenance robot, and achieve accurate prediction of material performance degradation. This method overcomes the limitations of traditional experimental methods, such as long time consumption, high cost, and difficulty in comprehensively covering all parameter combinations, and provides strong support for material selection, design, and optimization. And it combines multi-scale numerical simulation with experimental verification to form a complete evaluation system. Through numerical simulation, the performance degradation of materials under different helium bubble sizes, numbers, and dose rates can be quickly evaluated, greatly improving the evaluation efficiency. At the same time, experimental verification ensures the accuracy of the numerical simulation results, making the evaluation results more reliable.

[0048] The numerical simulation and evaluation method in the present invention provides a new perspective and means for materials science research. Through in-depth research on the degradation of material properties induced by helium bubbles, the microscopic structure evolution mechanism and macroscopic property degradation law of materials under irradiation environment can be revealed, providing a theoretical basis and experimental guidance for the research and development of new anti-irradiation materials. By accurately predicting and evaluating the performance degradation of robot component materials, potential safety hazards can be detected in a timely manner, avoiding failures or accidents caused by performance degradation during the service process of components. This helps to reduce the maintenance cost of nuclear facilities and improve the overall operation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0050] Figure 1 It is a schematic flow chart of the method provided by the present invention;

[0051] Figures 2a - 2e It is a SRIM simulation map of helium ions on tungsten alloy at different energies provided by the present invention, where Figure 2a is 200 Kev; Figure 2b is 300 Kev; Figure 2c is 400 Kev; Figure 2d is 500 Kev Figure 2e is 600 Kev;

[0052] Figure 3 It is the number of vacancies of tungsten at different energies provided by the present invention;

[0053] Figure 4 It is a formation diagram of helium-vacancy clusters in the LAMMPS molecular dynamics simulation of helium on tungsten provided by the present invention;

[0054] Figure 5 It is a curve graph of cluster size distribution provided by the present invention;

[0055] Figure 6 It is a bar graph of helium diffusion coefficient provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0056] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0057] The embodiment of the present invention discloses a numerical simulation method for material performance degradation of key components of an inspection and maintenance robot induced by helium bubbles, such as Figure 1 Shown, including:

[0058] S1. Collect and analyze experimental data on key components and materials of inspection and maintenance robots in a nuclear radiation environment;

[0059] S2. Based on the SRIM / TRIM simulation model, the number of vacancies and off-site damage dose rate generated by each helium ion are calculated to quantify the initial conditions of radiation damage;

[0060] S3. Based on the experimental data and initial conditions, LAMMPS molecular dynamics is used to simulate the diffusion of helium atoms, the formation of helium-vacancy clusters, and dislocation interactions at the atomic scale, obtaining the cluster size distribution and helium diffusion coefficient.

[0061] S4. In Python, input the helium diffusion coefficient and cluster size distribution parameters obtained at the atomic scale and set the free energy functional parameters to obtain the equivalent porosity of the helium bubble;

[0062] S5. The degradation law of material properties is studied based on ABAQUS. By inputting the constitutive model of the material and the equivalent porosity of the helium bubble, the degradation law of the mechanical properties is obtained.

[0063] In a specific embodiment, (1) acquisition of experimental data

[0064] a) Basic physical property collection: Obtain the physical properties of tungsten alloy, including:

[0065] Density 19.3±0.2g / cm 3 ;

[0066] Elastic modulus 410±15GPa( <100> crystal orientation);

[0067] Yield strength ≥850MPa (room temperature);

[0068] Elongation 2-15% (related to recrystallization degree);

[0069] b) Establish material database: Construct thermodynamic database of W alloy;

[0070] c) Defect feature extraction: Obtain the initial dislocation density ρ0 through TEM;

[0071] The experimental parameters in S1 include:

[0072] 1) The incident energy range of helium ions is 200 keV - 600 MeV

[0073] 2) Physical parameters of the alloy material: density 7.8 - 18.6 g / cm 3 , and the percentage error of the composition is ≤ 0.5 wt.%.

[0074] 3) The number of atoms is set according to the irradiation dose at 1×10 15 -5×10 20 ions / cm 2 set

[0075] 4) The incident target depth is obtained through the Monte Carlo simulation of SRIM

[0076] In a specific embodiment, S2 specifically includes:

[0077] a) SRIM / TRIM modeling:

[0078] Input the proportion of W alloy element (W: 92 ± 0.5 wt.%)

[0079] Set the incident energy gradient: 200 - 600 MeV (step size 0.5 MeV)

[0080] The number of Monte Carlo simulations is ≥ 10000 times

[0081] b) Output key parameters: peak depth of helium concentration; vacancy generation rate; displacement damage dose rate.

[0082] In a specific embodiment, the equation for the displacement damage dose rate is:

[0083]

[0084] Among them, I - beam current intensity, unit A; q - charge of each helium ion; A - irradiation area, unit cm 2 ; N d — number of displaced atoms generated by each helium ion; N atom — material atomic density, unit atoms / cm 3 .

[0085] The SRIM / TRIM calculation adopts the Full Damage Cascades mode, and the statistical average result is obtained through 10000 ion trajectory simulations. The output data includes:

[0086] 1) Helium ion concentration distribution curve

[0087] 2) Displacement damage (dpa) distribution nephogram

[0088] 3) Generation rate of vacancy-interstitial atom pairs

[0089] 4) The calculation results are output in.txt format as the initial boundary conditions for LAMMPS molecular dynamics simulation;

[0090] In a specific embodiment, the S3 specifically includes:

[0091] a) LAMMPS modeling:

[0092] Construct a 3D model with dimensions of 50×50×50 nm 3 , and the number of atoms ≥ 3×10 6 ;

[0093] Use the MEAM potential function to describe the many-body interaction of W-He;

[0094] Set the temperature field from 300 - 2000 K with a gradient of 10 K / ps;

[0095] b) Key process simulation: Helium diffusion trajectory tracking; Calculation of the interaction energy of dislocation loops; Output the histogram of cluster size distribution, and then obtain the cluster size distribution and helium diffusion coefficient.

[0096] Specifically, perform multi-scale modeling: Establish a cross-scale coupling model including the atomic scale - mesoscopic scale - macroscopic scale, where the atomic scale outputs helium diffusion coefficient parameters to the mesoscopic scale, and the mesoscopic scale outputs helium bubble morphology parameters to the macroscopic scale;

[0097] The atomic scale modeling specifically includes:

[0098] a) Use LAMMPS to construct a W alloy system containing ≥ 10 6 atoms;

[0099] b) Embed the EAM potential function to describe the He-W interaction;

[0100] c) Perform 1 ns molecular dynamics simulation in the NVT ensemble with a time step of 1 fs;

[0101] d) Calculate the helium diffusion coefficient by the mean square displacement (MSD) method;

[0102] Use the LAMMPS trajectory file and calculate the MSD:

[0103] MSD(t) = <|r(t) - r(0)| 2 > = 6Dt

[0104] Among them, r(t) is the atomic position at time t, and 《·》 represents the average over multiple atoms and time.

[0105] Mesoscopic-scale phase-field modeling includes:

[0106] a) Establish a helium bubble evolution model based on the Cahn-Hilliard equation: where the chemical free energy density F includes an elastic strain energy term and a concentration gradient term;

[0107] b) Input the helium diffusion coefficient obtained at the atomic scale as the mobility parameter M;

[0108] c) Solve using the semi-implicit Fourier spectral method with a time step of 0.1 s;

[0109] Specifically, it is used to numerically solve the Cahn-Hilliard equation established in step a):

[0110]

[0111] where the free energy functional F includes an elastic strain term and a concentration gradient term, is the variational derivative of the free energy functional F with respect to the concentration c, and the equation is complex and contains a fourth-order derivative.

[0112] d) Output the average radius R ∈ [1, 50] nm of the helium bubble and the number density;

[0113] Among them, it also includes Python data conversion

[0114] a) Read the MSD data and cluster distribution output by LAMMPS

[0115] b) Calculate the equivalent porosity: f = 4πR 3 ρ / 3

[0116] c) Generate an ABAQUS input file

[0117] d) Output the key parameters: the average radius R ∈ [1, 50] nm of the helium bubble, the number density ρ ∈ [10 21 -10 24 m -3 .

[0118] The specific implementation of macroscopic-scale modeling is as follows:

[0119] a) Establish a three-dimensional solid model in ABAQUS with a mesh size ≤ R / 5

[0120] b) Adopt the Gurson-Tvergaard-Needleman damage constitutive model: where the porosity f is obtained by converting the helium bubble parameters: f = 4πR 3 ρ / 3;

[0121] c) Obtain the elastic modulus decay rate through uniaxial tensile simulation;

[0122] d) Calculate the yield strength degradation rate based on the J-integral method;

[0123] Numerical implementation

[0124] ABAQUS operation:

[0125] Use the CONTOUR INTEGRAL function to calculate the J-integral value of the specified path. Extract the strain energy density and stress field data through Field Output.

[0126] The specific formula is:

[0127] Calculation formula:

[0128]

[0129] where W is the strain energy density, δ ij is the Kronecker delta. When i = j, δ ij = 1; when i ≠ j, δ ij = 0, σ ij is the stress tensor, u i is the displacement field, and n j is the path normal vector.

[0130] In a specific embodiment, the S4 specifically includes:

[0131] Through LAMMPS molecular dynamics simulation, the cluster size distribution and helium diffusion coefficient output at the atomic scale are obtained, as Figure 5 and Figure 6 shown.

[0132] Next, a specific example is introduced to further illustrate the method of the present invention.

[0133] (1) Construction of the material parameter system.

[0134] Collect experimental data of the key components of the inspection and maintenance robot (taking tungsten-based alloy as an example) in the nuclear irradiation environment:

[0135] Helium bubble characteristic parameters: Obtain the bubble diameter distribution (1 - 50 nm) and the grain boundary segregation ratio (≥65%) through TEM;

[0136] Mechanical property baseline: Test the hardness before irradiation (12 - 15 GPa) and elastic recovery rate using nanoindentation method.

[0137] (2) Quantitative analysis of irradiation damage:

[0138] Figures 2a - 2e SRIM simulation spectra of tungsten alloy by helium ions at different energies, where Figure 2a is 200 Kev; Figure 2b is 300 Kev; Figure 2c is 400 Kev; Figure 2d is 500 Kev Figure 2e is 600 Kev;

[0139] Helium ion implantation simulation is carried out based on SRIM / TRIM software:

[0140] a. Input beam current intensity and irradiation area

[0141] b. When calculating the dose rate, substitute the beam current intensity, ion charge (+2 valence state) and irradiation area into the flux density formula to obtain the number of displaced atoms per unit time (dpa / s);

[0142] c. Output the damage distribution cloud map, and focus on extracting the concentration of displaced atoms in the peak damage area (depth 0 - 1.5 μm); Figure 3 is the number of vacancies in tungsten at different energies;

[0143] (3) Atomic-scale evolution simulation

[0144] Construct a cross-scale model in LAMMPS:

[0145] a. Adopt a 50×50×50 nm 3 computational domain and embed the MEAM many-body potential function to describe the W-Cr-He interaction;

[0146] b. Set the temperature gradient field (30), simulate the thermal activation diffusion process of helium atoms;

[0147] C. Statistically analyze the nucleation threshold of helium-vacancy clusters (≥3 vacancies combined) through trajectory tracking;

[0148] As Figure 4 shown, the formation diagram of helium-vacancy clusters in the LAMMPS molecular dynamics simulation of helium in tungsten;

[0149] Realize cross-scale damage prediction in ABAQUS:

[0150] Convert the helium bubble parameters (average radius, number density) output by the mesoscopic model into the porosity variable of the GTN constitutive model; among them, set the GTN constitutive model:

[0151] Initial porosity f0 = 0.001 - 0.1

[0152] Critical porosity f_c = 0.15;

[0153] Construct a three-dimensional solid model and apply the actual working condition loads (multi-axial stress ratio of 0.5 - 1.2);

[0154] Obtain the performance degradation law through parametric scanning: the elastic modulus decay rate reaches 20 - 35% (helium bubble density > 1×10 23 m -3 ), and the fatigue crack growth rate increases by 2 - 3 orders of magnitude.

[0155] A numerical simulation system for the performance degradation of key components of a helium bubble-induced inspection and maintenance robot, comprising:

[0156] S1. Collect and analyze the experimental data of the key component materials of the inspection and maintenance robot in the nuclear radiation environment;

[0157] S2. Based on the simulation model of SRIM / TRIM, calculate the number of vacancies and the displacement damage dose rate generated by each helium ion, and quantify the initial conditions of radiation damage;

[0158] S3. Based on the obtained experimental data and initial conditions, use LAMMPS molecular dynamics to simulate the diffusion of helium atoms, the formation of helium-vacancy clusters, and the interaction with dislocations at the atomic scale, and obtain the cluster size distribution and helium diffusion coefficient;

[0159] S4. In Python, input the helium diffusion coefficient and cluster size distribution parameters obtained at the atomic scale and set the free energy functional parameters to obtain the equivalent porosity of helium bubbles;

[0160] S5. Based on ABAQUS, conduct research on the material performance degradation law. By inputting the constitutive model of the material and the equivalent porosity of helium bubbles, obtain the degradation law of mechanical properties.

[0161] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple. For the relevant parts, reference can be made to the description in the method part.

[0162] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art. The general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A numerical simulation method for the degradation of the material properties of key components of a helium bubble-induced inspection, repair and maintenance robot, characterized in that, Including: S1. Collect and analyze the experimental data of the key component materials of the inspection and maintenance robot in the nuclear radiation environment; S2. Based on the simulation model of SRIM / TRIM, calculate the number of vacancies and the displacement damage dose rate generated by each helium ion, and quantify the initial conditions of irradiation damage; S3. Based on the obtained experimental data and initial conditions, use LAMMPS molecular dynamics to simulate the diffusion of helium atoms, the formation of helium-vacancy clusters and the interaction with dislocations at the atomic scale, and obtain the cluster size distribution and helium diffusion coefficient; S4. In Python, input the helium diffusion coefficient and cluster size distribution parameters obtained at the atomic scale and set the free energy functional parameters to obtain the equivalent porosity of helium bubbles; S5. Based on ABAQUS, study the law of material property degradation. By inputting the constitutive model of the material and the equivalent porosity of helium bubbles, obtain the law of mechanical property degradation.

2. The numerical simulation method for the degradation of the material properties of the key components of the inspection, repair and maintenance robot induced by helium bubbles according to claim 1, wherein, The experimental data includes the basic physical property parameters of the key component materials, the thermodynamic database of W alloy, and the extracted defect characteristics. Among them, the basic physical property parameters specifically include density, elastic modulus, yield strength, tensile strength, and elongation; the extracted defect characteristics include the initial dislocation density obtained by TEM.

3. A numerical simulation method for the degradation of the material properties of key components of a helium bubble-induced inspection, repair, and maintenance robot according to claim 1, characterized in that, The specific content of S2 includes: a) SRIM / TRIM modeling: Input the proportion of alloying elements; Set the incident energy gradient; The number of Monte Carlo simulations ≥ 10000 times; b) Output key parameters: peak depth of helium concentration; vacancy generation rate; displacement damage dose rate.

4. A numerical simulation method for the degradation of the material properties of key components of a helium bubble-induced inspection, repair, and maintenance robot according to claim 3, characterized in that, The equation of the displacement damage dose rate is: Where, I is the beam current intensity, with the unit of A; q is the electric charge of each helium ion; A is the irradiation area, with the unit of cm 2 ; N d — the number of displaced atoms produced by each helium ion; N atom — the atomic density of the material, with the unit of atoms / cm 3 .

5. A numerical simulation method for the degradation of the material properties of key components of a helium bubble-induced inspection, repair, and maintenance robot according to claim 1, characterized in that The specific content of S3 includes: a) LAMMPS modeling: Build a 3D model with dimensions of 50×50×50 nm 3 , the number of atoms ≥ 3×10 6 ; Use the MEAM potential function to describe the many-body interaction of W-He; Set the temperature field from 300 to 2000K, with a gradient of 10K / ps; b) Key process simulation: tracking the diffusion trajectory of helium; calculating the interaction energy of dislocation loops; outputting the histogram of cluster size distribution, and then obtaining the cluster size distribution and helium diffusion coefficient.

6. A numerical simulation method for the degradation of the material properties of key components of a helium bubble-induced inspection, repair, and maintenance robot according to claim 1, characterized in that The specific content of S4 includes: Data conversion in Python: a) Read the MSD data and cluster distribution output by LAMMPS b) Calculate the equivalent porosity: f = 4πR 3 ρ / 3 c) Generate ABAQUS input files d) Output key parameters: the average radius R of helium bubbles ∈ [1, 50]nm, number density.

7. A numerical simulation method for the degradation of the material properties of key components of a helium bubble-induced inspection, repair and maintenance robot according to claim 1, characterized in that The specific content of S4 includes: Implement cross-scale damage prediction in ABAQUS: Convert the average radius and number density of helium bubbles output by the mesoscopic model into the porosity variable of the GTN constitutive model; Construct a three-dimensional solid model, apply the actual working condition load, and the multiaxial stress ratio is 0.5 - 1.2; Obtain the performance degradation law through parametric scanning: when the elastic modulus decay rate reaches 20 - 35% and the helium bubble density > 1×10 23 m -3 , the fatigue crack growth rate increases.

8. A numerical simulation system for the degradation of the material properties of key components of a helium bubble-induced inspection, repair, and maintenance robot, characterized in that, Apply the numerical simulation method for the performance degradation of the key component materials of the inspection and maintenance robot induced by helium bubbles according to any one of claims 1 - 7, including: S1. Collect and analyze the experimental data of the key component materials of the inspection and maintenance robot in the nuclear radiation environment; S2. Based on the simulation model of SRIM / TRIM, calculate the number of vacancies and the displacement damage dose rate generated by each helium ion, and quantify the initial conditions of irradiation damage; S3. Based on the obtained experimental data and initial conditions, use LAMMPS molecular dynamics to simulate helium atom diffusion, the formation of helium-vacancy clusters, and the interaction with dislocations at the atomic scale, and obtain the cluster size distribution and helium diffusion coefficient; S4. In Python, input the helium diffusion coefficient and cluster size distribution parameters obtained at the atomic scale and set the free energy functional parameters to obtain the equivalent porosity of helium bubbles; S5. Based on ABAQUS, study the law of material property degradation. By inputting the constitutive model of the material and the equivalent porosity of helium bubbles, obtain the law of mechanical property degradation.

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