Construction method of viscoplastic constitutive model of MEMS device binding material in deep space environment
By constructing an irradiation-temperature coupled viscoplastic constitutive model, the problem of insufficient accuracy in predicting the mechanical behavior of MEMS device bonding materials under high temperature and irradiation environments in existing technologies is solved. This achieves high-precision mechanical behavior prediction and device reliability assessment, improving the applicability and engineering application value of the model.
Patent Information
- Application Number
- CN202511410463.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-29
- Publication Date
- 2026-01-09
AI Technical Summary
In the prior art, the mechanical behavior of MEMS device bonding materials under high temperature and irradiation environments exhibits significant viscoplastic characteristics. However, existing constitutive models mostly consider temperature or irradiation factors alone, resulting in insufficient prediction accuracy. Furthermore, the nonlinear coupling mechanism between irradiation and temperature lacks quantitative characterization, which limits the applicability of the models under complex operating conditions.
A viscoplastic constitutive model based on irradiation-temperature bivariate coupling was constructed. Through microscopic damage mechanism modeling and multi-field coupling analysis, the evolution law of mechanical behavior of the bonded material was revealed. Monte Carlo and molecular dynamics simulations were used to establish the defect-mechanical property mapping relationship. Combined with finite element verification and dynamic correction, a constitutive equation containing piecewise correction terms was constructed.
It significantly improves the prediction accuracy of the mechanical behavior of bonding materials in deep space environment, provides theoretical support for the suppression of residual stress and reliability assessment of MEMS devices, and enhances the long-term prediction capability and engineering application value of the model.
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Abstract
Description
Technical Field
[0001] This invention relates to the fields of microelectromechanical systems (MEMS), materials science and engineering, and model simulation technology. Specifically, it relates to a method for constructing a viscoplastic constitutive model of bonding materials for MEMS devices coupled with space irradiation and temperature effects. This method is applicable to the prediction of mechanical properties and lifetime assessment of materials in extreme environments such as nuclear energy and aerospace. Background Technology
[0002] Space stations, spacecraft, and landers require long-term operation in deep space environments. The bonding materials of MEMS devices exhibit significant viscoplastic characteristics under high temperature and irradiation conditions. Their constitutive relations are influenced by the dual coupling of irradiation damage (such as atomic displacement damage) and temperature (thermal activation effect, creep), leading to microscopic damage to the bonding materials and subsequently viscoplastic deformation and creep relaxation. This results in the dynamic evolution of residual stress, causing systematic errors such as zero-bias drift and frequency drift. Current technologies often use constitutive models that consider temperature or irradiation factors individually, or employ linear superposition to handle bivariate effects, resulting in insufficient accuracy in predicting the dynamic response of materials.
[0003] Furthermore, the lack of quantitative characterization of the nonlinear coupling mechanism between irradiation and temperature (such as irradiation-accelerated diffusion and heat-irradiation synergistic damage) limits the applicability of the model under complex working conditions.
[0004] Therefore, there is an urgent need for a method for constructing viscoplastic constitutive models that comprehensively considers irradiation, temperature, and material properties. Summary of the Invention
[0005] To address the aforementioned technical issues, this application provides a method for constructing a viscoplastic constitutive model based on irradiation-temperature dual-variable coupling. Through microscopic damage mechanism modeling and multi-field coupling analysis, it reveals the evolution law of the mechanical behavior of bonding materials in space environment, providing theoretical support for residual stress suppression and reliability assessment of MEMS devices.
[0006] This application provides a method for constructing a viscoplastic constitutive model of the bonding material for MEMS devices in deep space environments, including: Irradiation-temperature coupling experimental data of the bonding material were collected to obtain the first data, including stress-strain curves, steady-state creep rate, elastic modulus and fracture toughness data under different irradiation doses and temperatures; Based on the first data, the atomic displacement damage and ionization damage distribution of the bonding material under irradiation were simulated, and the defect density and energy deposition were calculated; in addition, the irradiation-induced molecular chain breakage, cross-linking and microcrack propagation process were simulated, and the defect density-mechanical property mapping relationship was established. A first viscoplastic constitutive equation model is constructed, which includes the viscoplastic strain rate equation, the elastic modulus equation, and the damage evolution equation. Based on experimental data and simulation results, the parameters of the first viscoplastic constitutive equation model were calibrated and verified by finite element method, resulting in the second viscoplastic constitutive equation model. By combining the second viscoplastic constitutive equation model with multiphysics simulation of MEMS devices, the spatiotemporal evolution of residual stress is predicted, and the irradiation damage parameters are dynamically corrected.
[0007] In one possible implementation, the irradiation-temperature coupling experimental data includes data obtained from gradient irradiation metrology and temperature cycling tests on the adhesive material.
[0008] In one possible implementation, the viscoplastic strain rate equation is:
[0009] in, Indicates viscoplastic strain rate, This is the temperature correlation coefficient. The initial activation energy, For effective stress, V To activate the volume, k Boltzmann's constant, T Absolute temperature α The radiation sensitivity coefficient, D For drag stress, Back pressure; The irradiation damage variable; the drag stress D、 back pressure , This is a correction value after irradiation.
[0010] Furthermore, the drag stress D The corrected formula is:
[0011] Where D is the drag stress after irradiation, and D0 is the initial drag stress before irradiation. This is a low-irradiation linear correction factor. This is a high-irradiation nonlinearity correction coefficient. dose This is the irradiation dose. Here, H represents the irradiation damage threshold, and H is the Heaviside step function.
[0012] Furthermore, the back pressure The corrected formula is:
[0013] in, The back pressure after irradiation. The initial back pressure before irradiation. This is a low-irradiation linear correction factor. This is a high-irradiation nonlinearity correction coefficient. This represents the irradiation damage threshold.
[0014] Furthermore, the aforementioned The corrected formula is:
[0015] in, This represents the radiation damage variable after irradiation time t. This represents the initial irradiation damage variable before irradiation. Indicates irradiation The rate of change of the radiation damage variable at any given time.
[0016] In one possible implementation, the formula for the elastic modulus is:
[0017] in, E This represents the elastic modulus after irradiation. This represents the elastic modulus in the unirradiated state. This is a low-irradiation linear correction factor. This is a high-irradiation nonlinearity correction coefficient. It is a nonlinear hardening exponent. This represents the irradiation damage threshold.
[0018] In one possible implementation, the damage evolution equation is:
[0019] in, The rate of change of the irradiation damage variable describes the cumulative process of damage over time, temperature, and stress. This is the damage rate constant, reflecting the inherent rate of irradiation damage accumulation; k τ is the Boltzmann constant; T(τ) and σ(τ) represent the functions of temperature and stress as a function of time, respectively; This is the activation energy for radiation damage; m It is a stress sensitivity index that correlates stress level with damage accumulation rate.
[0020] In one possible implementation, calibrating the parameters of the first constitutive equation model by combining experimental data and simulation results includes: The parameters of the first viscoplastic constitutive equation model were calibrated using the nonlinear least squares method, combining the initial data and simulation results. These parameters include the temperature correlation coefficient. Initial activation energy Activation volume Irradiation sensitivity coefficient Initial drag stress Nonlinear hardening index Initial back pressure Initial elastic modulus Initial irradiation damage variables (Generally 0), damage rate constant Activation energy of radiation damage Stress sensitivity index and each correction factor; A finite element simulation model of the adhesive layer is established based on the calibrated first viscoplastic constitutive equation model to simulate its stress relaxation and creep behavior in a typical space environment; the deformation or stress relaxation curves obtained from the simulation are compared and verified with the corresponding data in the first data; after the verification is passed, the second viscoplastic constitutive equation model is obtained.
[0021] In one possible implementation, the combination of the second viscoplastic constitutive equation model with MEMS device multiphysics simulation to predict the spatiotemporal evolution of residual stress and dynamically correct irradiation damage parameters includes: By combining the constitutive model with multiphysics simulation of MEMS devices, the spatiotemporal evolution of residual stress in the adhesive layer during on-orbit operation of the device is predicted. Irradiation damage parameters were dynamically corrected through chip-level micro-heating sheet annealing experiments.
[0022] The method provided in this application, through microscopic damage mechanism modeling and multi-field coupling analysis, comprehensively considers irradiation, temperature, and material properties to reveal the evolution law of the mechanical behavior of bonding materials in space environment, providing theoretical support for residual stress suppression and reliability assessment of MEMS devices. The method presented in this application is the first to propose a mechanism-driven constitutive model based on the nonlinear coupling of irradiation and temperature, overcoming the limitations of the simple superposition of irradiation and temperature effects in existing technologies. It reveals the microscopic damage mechanism through multi-scale simulation and constructs a constitutive equation containing piecewise correction terms, which can accurately describe the complex evolution process of materials from "low-dose linear response" to "high-dose nonlinear saturation".
[0023] The beneficial effects of this application are as follows: 1. High-precision prediction: This method establishes a nonlinear coupling mechanism between irradiation and temperature, abandoning the traditional linear superposition assumption, and significantly improves the prediction accuracy of the mechanical behavior of bonding materials (such as creep and stress relaxation) in deep space environment.
[0024] 2. Mechanism-driven: Through multi-scale simulations such as Monte Carlo and molecular dynamics, the generation and evolution mechanism of irradiation damage (displacement damage, ionization damage, molecular chain breakage / crosslinking) is revealed at the atomic / molecular level, and a quantitative mapping relationship between "defect-mechanical properties" is established, giving the constitutive model a solid physical basis rather than empirical fitting.
[0025] 3. Dynamic correction capability: A chip-level micro-heating sheet annealing experiment is proposed to dynamically correct the irradiation damage parameters in the model, so that the model can adapt to the long-term performance evolution of the device during on-orbit operation, which solves the problem of poor applicability of traditional static models and improves the long-term prediction capability of the model.
[0026] 4. Engineering Applicability: The constructed constitutive model can be directly embedded into commercial finite element software (such as Abaqus) and combined with multiphysics simulation of MEMS devices, providing a direct theoretical tool for low-stress packaging design and reliability assessment of devices, and has good prospects for engineering applications. Attached Figure Description
[0027] Figure 1 This is a flowchart illustrating the method provided in an embodiment of this application. Detailed Implementation
[0028] The content of this application will be further described below with reference to specific embodiments, but the content of this application is not limited thereto.
[0029] In existing technologies, constitutive models often consider temperature or irradiation factors individually, or use linear superposition to handle bivariate effects, resulting in insufficient accuracy in predicting the dynamic response of materials. In addition, the nonlinear coupling mechanism between irradiation and temperature (such as irradiation-accelerated diffusion and heat-irradiation synergistic damage) lacks quantitative characterization, which limits the applicability of the model under complex working conditions.
[0030] In view of this, this application provides a method for constructing a viscoplastic constitutive model of the bonding material of MEMS devices in a deep space environment.
[0031] See Figure 1 The method described in this application includes the following steps: S101. Collect irradiation-temperature coupling experimental data of the bonding material, obtaining initial data including stress-strain curves, steady-state creep rate, elastic modulus, and fracture toughness at different irradiation doses and temperatures. It should be noted that this step is fundamental to all subsequent modeling and calibration; the acquired experimental data is used to drive and validate the model. In the MEMS device manufacturing process, the bonding and fixing of crystalline components is a critical step. Selecting a suitable adhesive can effectively improve structural strength and environmental resistance. Common bonding materials include: silver-doped epoxy resin H20E, silver-doped epoxy resin P-1011, silver glass adhesive QM-3555R, eutectic solder Au-Ge, and eutectic solder Au-Sn.
[0032] In one possible implementation, S101 includes: S101a. Using a dynamic thermomechanical analyzer (DMA) coupled with an accelerator system, gradient irradiation doses (e.g., 0~1×10⁻⁶) are applied to typical MEMS device bonding materials (such as conductive silver paste H₂OE). 4 Coupled testing of rad) and wide temperature range temperature cycling (e.g., -40℃ to 120℃).
[0033] This combined system enables in-situ or quasi-in-situ testing of irradiation and mechanical properties, ensuring data accuracy. The data acquired through the tests constitutes the irradiation-temperature coupling experimental data.
[0034] Based on the irradiation-temperature coupling experimental data obtained from S101a, key mechanical performance parameters under different irradiation doses and temperature combinations were extracted and organized, including stress-strain curves, steady-state creep rate, elastic modulus, and fracture toughness data. These data together constitute the "first data" and will be used for subsequent simulations, modeling, and parameter calibration.
[0035] S102. Based on the first data, simulate the atomic displacement damage and ionization damage distribution of the bonding material under irradiation, calculate the defect density and energy deposition; and simulate the irradiation-induced molecular chain breakage, cross-linking and microcrack propagation process to establish the defect density-mechanical property mapping relationship.
[0036] In one possible implementation, S102 includes: S102a, Monte Carlo Simulation: Based on the first data, the transport process of particles in the binder material is simulated using SRIM software to accurately calculate the spatial distribution of atomic displacement damage, defect density distribution, and ionization damage distribution. These simulation results are used to quantify the degree of microscopic damage caused by irradiation.
[0037] S102b, Molecular Dynamics Calculation: Based on the material composition information and defect density distribution results, the molecular dynamics (MD) method is used in combination with the deep learning potential function (DP-Tab) to simulate the impact effect of the irradiation process on the polymer molecular chain and obtain the defect density-mechanical property mapping relationship.
[0038] Furthermore, S102b includes: (1) Simulating the damage process: High-energy particle impacts are introduced into the MD model to simulate the molecular chain breakage and cross-linking phenomena caused by free radical recombination. This step tracks the initiation and propagation path of microcracks through long-term simulation.
[0039] (2) Establishing a mapping relationship: Statistically analyze the microstructural parameters such as the average fracture length of molecular chains, crosslinking density, and volume fraction of micropores or microcracks under different irradiation doses; perform correlation analysis between these microscopic parameters and the macroscopic mechanical properties of the material (such as a decrease in elastic modulus and a reduction in fracture toughness); and use data fitting or machine learning methods to establish a quantitative mapping relationship between "defect density" and "mechanical property degradation". For example, a functional relationship of "for every X% increase in crosslinking density, the elastic modulus increases by Y%" can be obtained.
[0040] S103. Construct the first viscoplastic constitutive equation model.
[0041] This step, based on the microscopic mechanisms and mapping relationships established in S102, constructs a constitutive equation that reflects the irradiation-temperature coupling effect. The results of S102 (especially the defect density-mechanical property mapping relationship) are the theoretical basis for constructing this model.
[0042] In one possible implementation, the first viscoplastic constitutive equation model consists of three parts: a strain rate equation, an elastic modulus equation, and a damage evolution equation.
[0043] Furthermore, combining thermal activation theory and nonlinear hardening mechanism, the following viscoplastic strain rate equation is established:
[0044] in, Indicates viscoplastic strain rate, This is the temperature correlation coefficient. The initial activation energy, For effective stress, V To activate the volume, k Boltzmann's constant, T Absolute temperature α The radiation sensitivity coefficient, D For drag stress, Back pressure; The irradiation damage variable; the drag stress D、back pressure , This is a correction value after irradiation.
[0045] It should be noted that irradiation introduces defects (such as vacancies and interstitial atoms), increasing hardening resistance. Under low irradiation, the material response is mainly linear hardening or softening, with relatively mild molecular chain crosslinking or degradation. Under high irradiation, the material enters a nonlinear hardening or softening stage, with significant changes in molecular structure (such as crosslink density saturation). Irradiation is classified into low and high irradiation based on the irradiation damage threshold; values less than or equal to the threshold are considered low irradiation, and values greater than the threshold are considered high irradiation. Therefore, it is necessary to modify the material parameters according to the irradiation level to reflect the nonlinear coupling effect in S102. The specific correction formula is as follows: The corrected formula for drag stress D is:
[0046] Where D is the drag stress after irradiation, and D0 is the drag stress in the unirradiated state. This is a low-irradiation linear correction factor. This is a high-irradiation nonlinearity correction coefficient. dose This is the irradiation dose. Here, H represents the irradiation damage threshold, and H is the Heaviside step function.
[0047] back pressure The corrected formula is:
[0048] in, The back pressure after irradiation. The back pressure under unirradiated conditions. This is a low-irradiation linear correction factor. This is a high-irradiation nonlinearity correction coefficient. This represents the irradiation damage threshold.
[0049] The corrected formula is:
[0050] in, This represents the radiation damage variable after irradiation time t; This represents the initial irradiation damage variable before irradiation; Indicates irradiation The rate of change of the radiation damage variable at any given time.
[0051] Elastic modulus:
[0052] Among them, among them, EThis represents the elastic modulus after irradiation. This represents the elastic modulus in the unirradiated state. This is a low-irradiation linear correction factor. This is a high-irradiation nonlinearity correction coefficient. It is a nonlinear hardening exponent. This is the radiation damage threshold (determined experimentally).
[0053] Damage evolution equation:
[0054] in, The rate of change of the irradiation damage variable describes the cumulative process of damage over time, temperature, and stress. This is the damage rate constant, reflecting the inherent rate of irradiation damage accumulation; k τ is the Boltzmann constant; T(τ) and σ(τ) represent the functions of temperature and stress as a function of time, respectively; This is the activation energy for radiation damage; m This is a stress sensitivity index that correlates stress level with damage accumulation rate. The equation reflects the accelerating effect of temperature-irradiation synergistic damage.
[0055] S104. Combining experimental data and simulation results, calibrate the constitutive equation model parameters and perform finite element verification to obtain the second viscoplastic constitutive equation model. This step utilizes the experimental data from S101 and the preliminary model from S103 to obtain a verified final model that can be used for engineering simulation through parameter calibration and verification.
[0056] In one possible implementation, S104 includes: S104a. Multi-source data fitting: Using the nonlinear least squares method, and combining the simulation results obtained from the simulation of the first viscoplastic constitutive equation model in finite element software with the first data (such as stress-strain curves and creep rate), the parameters of the first viscoplastic constitutive equation model are calibrated. The calibrated model parameters include: temperature correlation coefficient. Initial activation energy Activation volume Irradiation sensitivity coefficient Initial drag stress Nonlinear hardening index Initial back pressure Initial elastic modulus Initial irradiation damage variables (Generally 0), damage rate constant Activation energy of radiation damage Stress sensitivity index and each correction factor ( ) and threshold (dose) th ).
[0057] S104b, Finite Element Verification: Based on the calibrated first viscoplastic constitutive equation model, a finite element simulation model of the adhesive layer is established to simulate its stress relaxation and creep behavior under typical space environments (such as specific temperature cycles and irradiation history); the deformation or stress relaxation curves obtained from the simulation are compared and verified with the corresponding data in the first data; after the verification is passed, the second viscoplastic constitutive equation model is obtained.
[0058] Furthermore, the method for establishing the finite element simulation model of the adhesive layer includes: embedding the first viscoplastic constitutive equation model into the UMAT (User Material Subroutine) of the Abaqus software.
[0059] For example, verification can be performed by setting a relative error threshold. For instance, if the relative error between the two is less than 10%, the model is considered valid, and the calibrated model is the "second viscoplastic constitutive equation model".
[0060] S105. Combine the second viscoplastic constitutive equation model with multiphysics simulation of MEMS devices to predict the spatiotemporal evolution of residual stress and dynamically correct the irradiation damage parameters. This step involves the application and closed-loop optimization of the model, transforming it from a static model into a dynamic model with self-learning capabilities.
[0061] In one possible implementation, S105 includes: S105a, Cross-scale Coupling: The second viscoplastic constitutive equation model is integrated into the three-dimensional finite element model of the MEMS device as the material constitutive model. The multiphysics field of the MEMS device includes: thermal field (generated by changes in ambient temperature and the device's own power consumption), force field (stress generated by the mismatch of the material's thermal expansion coefficients and the creep of the adhesive layer), and electric field (in some MEMS devices, the electric field affects material properties). Through multiphysics coupling simulation, the spatiotemporal evolution of residual stress in the adhesive layer during the device's on-orbit operation is predicted, providing design guidance for optimizing the packaging process and reducing initial residual stress.
[0062] S105b, Online Correction: In order to address the model drift problem that may occur during long-term on-orbit operation of the device, the model is dynamically corrected through chip-level micro-heater annealing experiments.
[0063] The specific method involves applying a controlled thermal pulse (via an integrated microheater) to the MEMS device during ground-based simulations or in-orbit recoverable testing to simulate the annealing process. By measuring the device's performance parameters (such as resonant frequency and zero bias) before and after annealing, the degree of recovery of the adhesive layer's mechanical properties (such as modulus and internal stress) is deduced. Based on this experimental data, key irradiation damage parameters (such as the damage rate constant) of the second viscoplastic constitutive equation model are dynamically modified. Damage variables (etc.). This closed-loop correction mechanism can significantly improve the prediction accuracy and long-term applicability of the model throughout the entire device lifecycle.
[0064] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the invention.
Claims
1. A method for constructing a viscoplastic constitutive model of the bonding material for MEMS devices in a deep space environment, characterized in that, include: Irradiation-temperature coupling experimental data of the bonding material were collected to obtain the first data, including stress-strain curves, steady-state creep rate, elastic modulus and fracture toughness data under different irradiation doses and temperatures; Based on the first data, the atomic displacement damage and ionization damage distribution of the bonding material under irradiation were simulated, and the defect density and energy deposition were calculated; in addition, the irradiation-induced molecular chain breakage, cross-linking and microcrack propagation process were simulated, and the defect density-mechanical property mapping relationship was established. A first viscoplastic constitutive equation model is constructed, which includes the viscoplastic strain rate equation, the elastic modulus equation, and the damage evolution equation. Based on experimental data and simulation results, the parameters of the first viscoplastic constitutive equation model were calibrated and verified by finite element method, resulting in the second viscoplastic constitutive equation model. By combining the second viscoplastic constitutive equation model with multiphysics simulation of MEMS devices, the spatiotemporal evolution of residual stress is predicted, and the irradiation damage parameters are dynamically corrected.
2. The construction method according to claim 1, characterized in that, The irradiation-temperature coupling experimental data includes data obtained from gradient irradiation metrology and temperature cycling tests on the adhesive material.
3. The construction method according to claim 1, characterized in that, The viscoplastic strain rate equation is as follows: in, Indicates viscoplastic strain rate, This is the temperature correlation coefficient. The initial activation energy, For effective stress, V To activate the volume, k Boltzmann's constant, T Absolute temperature α The radiation sensitivity coefficient, D For drag stress, Back pressure; The irradiation damage variable; the drag stress D、 back pressure , This is a correction value after irradiation.
4. The construction method according to claim 3, characterized in that, The drag stress D The corrected formula is: Where D is the drag stress after irradiation, and D0 is the initial drag stress before irradiation. This is a low-irradiation linear correction factor. This is a high-irradiation nonlinearity correction coefficient. dose This is the irradiation dose. Here, H represents the irradiation damage threshold, and H is the Heaviside step function.
5. The construction method according to claim 3, characterized in that, The back pressure The corrected formula is: in, The back pressure after irradiation. The initial back pressure before irradiation. This is a low-irradiation linear correction factor. This is a high-irradiation nonlinearity correction coefficient. This represents the irradiation damage threshold.
6. The construction method according to claim 1, characterized in that, The The corrected formula is: in, This represents the radiation damage variable after irradiation time t. This represents the initial irradiation damage variable before irradiation. Indicates irradiation The rate of change of the radiation damage variable at any given time.
7. The construction method according to claim 1, characterized in that, The formula for the elastic modulus is: in, E This represents the elastic modulus after irradiation. This represents the initial elastic modulus before irradiation. This is a low-irradiation linear correction factor. This is a high-irradiation nonlinearity correction coefficient. It is a nonlinear hardening exponent. This represents the irradiation damage threshold.
8. The construction method according to claim 1, characterized in that, The damage evolution equation: in, The rate of change of the irradiation damage variable describes the cumulative process of damage over time, temperature, and stress. This is the damage rate constant, reflecting the inherent rate of irradiation damage accumulation; k τ is the Boltzmann constant; T(τ) and σ(τ) represent the functions of temperature and stress as a function of time, respectively; This is the activation energy for radiation damage; m It is a stress sensitivity index that correlates stress level with damage accumulation rate.
9. The construction method according to claim 1, characterized in that, The calibration of the first constitutive equation model parameters, combining experimental data and simulation results, includes: The parameters of the first viscoplastic constitutive equation model were calibrated using the nonlinear least squares method, combining the initial data and simulation results. These parameters include the temperature correlation coefficient. Initial activation energy Activation volume Irradiation sensitivity coefficient Initial drag stress Nonlinear hardening index Initial back pressure Initial elastic modulus Initial irradiation damage variables Damage rate constant Activation energy of radiation damage Stress sensitivity index and each correction factor; A finite element simulation model of the adhesive layer is established based on the calibrated first viscoplastic constitutive equation model to simulate its stress relaxation and creep behavior in a typical space environment; the deformation or stress relaxation curves obtained from the simulation are compared and verified with the corresponding data in the first data; after the verification is passed, the second viscoplastic constitutive equation model is obtained.
10. The construction method according to claim 1, characterized in that, The method of combining the second viscoplastic constitutive equation model with MEMS device multiphysics simulation to predict the spatiotemporal evolution of residual stress and dynamically correct irradiation damage parameters includes: By combining the constitutive model with multiphysics simulation of MEMS devices, the spatiotemporal evolution of residual stress in the adhesive layer during on-orbit operation of the device is predicted. Irradiation damage parameters were dynamically corrected through chip-level micro-heating sheet annealing experiments.