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92 results about "Crystal plasticity" patented technology

Abstract. Besides Dislocation Dynamics, crystal plasticity can be considered a mesoscale formulation, since the details of the equations start at the scale of the crystal or grain. In this section, the topics of classical crystal plasticity formulations, kinematics, kinetics, and the polycrystalline average methods will be discussed.

Rolling contact fatigue pitting corrosion prediction method considering crystal plasticity, corresponding computer readable storage medium and electronic equipment

The invention belongs to the field of prediction of fatigue failure caused by surface defects under rolling contact loads, and particularly relates to a rolling contact fatigue pitting corrosion prediction method considering crystal plasticity, a corresponding computer readable storage medium and electronic equipment. The method comprises the following steps: S1, constructing a crystal plastic constitutive model of a coupling damage accumulation theory; s2, developing the model in the step 1 into a UMAT subprogram by using Fortran, and embedding ABAQUS into the UMAT subprogram; s3, establishing a representative volume element crystal plastic finite element model; s4, applying a periodic boundary condition and a shear load, obtaining a shear stress-strain curve, carrying out a torsional fatigue test, obtaining fatigue damage parameters of the material, and determining constitutive model parameters of the material; s5, establishing a crystal plastic finite element model of the roller and raceway contact pair; s6, applying boundary conditions in two steps; and S7, observing a damage evolution path to the surface, and obtaining the rolling contact fatigue pitting corrosion life. The method can fill the blank of rolling contact fatigue pitting corrosion prediction methods at present.
Owner:HARBIN INST OF TECH ZHENGZHOU RES INST +1

Nonlinear decoupling method and system of three-axis force sensor

The invention relates to the technical field of force sensors, and discloses a nonlinear decoupling method and system for a three-axis force sensor, and the method comprises the steps: collecting multi-dimensional original data, and carrying out the adaptive noise reduction, dynamic selection of a wavelet basis, and construction of a filtering matrix, and obtaining a noise reduction signal through calculation; constructing a dynamic PINN proxy model, fusing material parameters and environment parameters, outputting a stiffness matrix, establishing an online parameter updating mechanism, calculating the obtained optimization parameters, and constructing an enhanced dynamic compensation matrix; the output stiffness matrix and the enhanced dynamic compensation matrix are fused, and a main singular value is reserved; reconstructing to obtain a reconstructed strain field, establishing a multi-physics field coupling model to compensate quantum-thermal coupling errors, and compensating wire inductive coupling under high frequency; constructing a multi-scale graph structure, strengthening a loss function through physical constraint, performing crystal plasticity hysteresis compensation, fusing multi-scale features, and calculating and outputting a decoupling force value; and an intelligent calibration decision is established, the drift trend is predicted, and the calibration period is dynamically adjusted.
Owner:HARBIN INST OF TECH (SHENYANG) INTELLIGENT IND TECH CO LTD

Weld joint structure sample fatigue life prediction method considering microstructure characteristics

The invention discloses a weld structure sample fatigue life prediction method considering microstructure characteristics, which comprises the following steps of: acquiring microstructure crystal characteristics of a weld joint area of a weld structure sample; establishing a finite element model of a representative volume element considering microstructure crystal characteristics of the welding joint area; acquiring material parameters of the weld joint structure sample; and calculating the representative volume element finite element model containing the microstructure crystal characteristics of the welding joint area through the crystal plasticity constitutive model, and combining with the improved fatigue life prediction model to obtain the final fatigue life prediction value of the weld joint structure sample. Based on the improved fatigue life prediction model, the fatigue life of the weld joint structure sample can be predicted more accurately.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Modeling method and system of crystal plasticity finite element model for weld microstructure crystal plasticity

The invention relates to the technical field of metal material processing engineering, discloses a full-automatic full-process modeling method and system of crystal plasticity finite element model for laser welding weld, which adopts MATLAB to call ABAQUS and PYTHON for co-simulation programming. In this text, a full-automatic modeling method of the crystal plasticity finite element model for laser welding weld is proposed, and a one-key crystal plastic finite element model for laser welding weld is established based on EBSD experimental data. In addition, the full-process full-automatic modeling method of crystal plastic finite element for laser welding weld is universal, and can be used for the establishment of the crystal plasticity finite element model for the microstructure of the base material of aluminum alloy, titanium alloy, magnesium alloy, stainless steel and other materials.
Owner:HUAZHONG UNIV OF SCI & TECH

VPSC model construction method based on ABAQUS sub-model

The invention discloses a VPSC model construction method based on an ABAQUS sub-model, and belongs to the field of computational material science and engineering.The VPSC model construction method comprises the steps that a global model is established according to the size of a part, and an ABAQUS input file is generated; selecting a local area of a part in the global model, determining a unit number of the area, constructing a crystal plasticity constitutive model through UMAT, and adding a plurality of randomly oriented crystal grains to the local area in an ABAQUS input file to form a reference model; grain nodes and orientation information in the reference model are read through an ABAQUS script, a grain model is created, corresponding orientation is given to sub-models, sub-model boundary conditions consistent with global model deformation are applied to grain geometric boundaries, and a VPSC model is constructed. According to the method, the grain orientation is locally refined through the sub-model technology, and the VPSC sub-model is automatically generated in combination with the script, so that the calculation complexity is remarkably reduced.
Owner:NANTONG UNIV

Prediction method of high temperature creep life of nickel-based single crystal under the influence of orientation deviation

The present invention proposes a method for predicting the high-temperature creep life of nickel-based single crystals under the influence of orientation deviation, which relates to the field of reliability technology. The method comprises: establishing a three-dimensional finite element round rod model based on the dimensions of a nickel-based single crystal creep specimen; establishing a constitutive equation for the nickel-based single crystal based on crystal plasticity theory, wherein the constitutive equation for the nickel-based single crystal includes a deformation equation that considers orientation deviation and a damage equation that considers orientation deviation; combining the three-dimensional finite element round rod model and the nickel-based single crystal constitutive equation to perform creep finite element simulation calculations on the round rod model; and establishing a creep time-strain curve and predicting the creep life based on the results of the creep finite element simulation calculations. The present invention can relatively accurately evaluate and predict the high-temperature creep life of nickel-based single crystal turbine blades used in actual industrial manufacturing.
Owner:YANSHAN UNIV

Crystal plasticity and cohesion model coupling hydrogen induced cracking simulation method based on test

The invention discloses a test-based crystal plasticity and cohesion model coupling hydrogen induced cracking simulation method, which comprises the following steps: carrying out a hydrogen filling mechanical property test on a metal material to obtain a true stress-true strain curve of the metal material in a hydrogen environment; carrying out a hydrogen-filled fracture toughness test on the metal material to obtain a stress intensity factor of the metal material in a hydrogen environment; constructing a cohesion constitutive model; a metal material electron back scattering diffraction microscopic characterization test is carried out, microstructure characteristics are obtained, and a polycrystalline model is constructed; constructing a crystal plastic constitutive model; coupling crystal plasticity constitutive and cohesion constitutive, and calibrating crystal plasticity to-be-determined parameters by adopting a trial-and-error method; and carrying out finite element simulation analysis on hydrogen-induced cracking behaviors with different microstructure characteristics in a hydrogen environment to obtain stress-strain data and crack data of the hydrogen-induced cracking behaviors. According to the invention, high-precision simulation of the hydrogen-induced cracking micromechanism of the metal material in the hydrogen environment is realized.
Owner:SOUTHWEST PETROLEUM UNIV

Crystal plasticity finite element modeling method and device, medium and electronic equipment

The invention relates to the technical field of material analysis, in particular to a crystal plasticity finite element modeling method, a crystal plasticity finite element modeling device, a storage medium and electronic equipment. The crystal plasticity finite element modeling method comprises the following steps: collecting grain information of a given material sample; performing crystal grain division based on the crystal grain information to obtain a crystal grain data file, and determining grid parameters based on a crystal grain with a minimum crystal grain morphology area in the crystal grain information; creating a grain geometric model according to the grain data file, creating a grid model according to the grid parameters, and mapping the grain geometric model to the grid model to obtain a crystal plasticity finite element grid model; and endowing a boundary condition and a constitutive relation to the crystal plasticity finite element mesh model so as to realize crystal plasticity finite element simulation. According to the crystal plasticity finite element modeling method provided by the invention, the modeling calculation efficiency can be improved while the model precision is ensured.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Welding thermal stress simulation method, device and equipment based on crystal plasticity finite element and medium

The invention discloses a welding thermal stress simulation method, device, equipment and medium based on a crystal plasticity finite element, and relates to the technical field of welding thermal stress finite element simulation. The method comprises the steps that a sample is prepared according to a specific multi-phase metal material, and phase distribution and crystal orientation information of a two-dimensional plane of the material are obtained through a metallographic experiment; and a three-dimensional multi-grain model is constructed based on the two-dimensional information. According to the method, a crystal plastic constitutive model is adopted to describe the flowing behavior of the material at high temperature, crystal slippage and polycrystal interaction are considered, the influence on the material performance is reflected from the microstructure evolution level, and the problem that the influence on the macroscopic mechanical performance of a microstructure is difficult to capture in welding multiphase metal material simulation is solved; two-dimensional representation is obtained through a metallographic experiment, the Young modulus and rigidity matrix parameters are accurately calculated by combining forward stretching and shear simulation, the rigidity matrix precision is improved, a temperature field area is divided, stress evolution and residual stress are calculated by combining a thermal-elastic-plastic model, and the welding thermal stress calculation precision is improved.
Owner:WUHAN INST OF TECH +1

Notch structure fatigue life prediction method based on probability crystal plasticity

The invention discloses a notched structure fatigue life prediction method based on probabilistic crystal plasticity, is applied to the field of reliability analysis, and provides a probabilistic crystal plasticity modeling framework for solving the problems of notched effect (local stress concentration) and material uncertainty generally existing in notched metal structural parts under the action of external loads. And the influence of material dispersibility (including material performance and microstructure) on the fatigue life of the notched part is considered. According to the method, a dual-scale modeling method is adopted, the mechanical response of a notched sample is simulated by adopting Chboche and crystal plastic constitutive simulation in a macro-micro mode, the randomness of the microstructure of the material and the dispersity of the mechanical property are considered by adopting a Voronoi algorithm and a Latin hypercube sampling method, and the fatigue life under different loads is predicted by adopting a fatigue indication factor; and finally describing the dispersibility of the fatigue life by using a probability model.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA +1

Welded joint fatigue weak area evaluation method based on crystal plasticity

The invention discloses a method for evaluating a fatigue weak area of a welded joint based on crystal plasticity, which aims at the problem of fatigue failure of the welded joint caused by complex microstructures such as grain orientation difference and uneven grain size distribution, establishes a quantitative correlation model of grain orientation and size evolution through CPFEM, and combines a macro-micro cross-scale analysis method to evaluate the fatigue weak area of the welded joint. And precise prediction of local stress concentration and crack initiation behaviors of the welding joint under a real fatigue load working condition is realized, so that scientific evaluation of a fatigue weak region is completed. According to the method, an innovative framework of fatigue weak area evaluation is constructed through load working condition reduction and grain characteristic multi-scale coupling, so that excessive simplification of a traditional method on real load conditions is made up, the limitation that a traditional model is difficult to couple a microstructure and a real load is overcome, and the fatigue weakening quantization precision is remarkably improved; and a high-precision analysis technology is provided for anti-fatigue design, process optimization and service life evaluation of the engineering welding structure.
Owner:EAST CHINA UNIV OF SCI & TECH

Material life prediction method, prediction system and computer readable medium

The invention relates to a material life prediction method, a prediction system and a computer readable medium. The prediction method comprises the following steps: obtaining simulation results of crystal plasticity finite element models corresponding to a to-be-predicted material under loads of pure low-cycle fatigue, creep fatigue and high-low-cycle composite creep fatigue, and at least one group of actual test results corresponding to the to-be-predicted material under the loads of pure low-cycle fatigue, creep fatigue and high-low-cycle composite creep fatigue; according to the simulation result and the test result, determining a critical value of a fatigue indication factor, a critical value of a creep indication factor and parameters related to the creep indication factor under loads of pure low-cycle fatigue, creep fatigue and high-low-cycle composite creep fatigue; and establishing a life prediction equation based on crystal plasticity by utilizing a linear damage accumulation criterion, and predicting the cycle life of the to-be-predicted material under the cyclic load test condition.
Owner:AECC COMML AIRCRAFT ENGINE CO LTD +1

GCN-LSTM-based dual-phase titanium alloy grain level stress prediction method

The invention relates to the field of computer algorithms and material engineering, in particular to a two-phase titanium alloy grain level stress prediction method based on GCN-LSTM. Firstly, a GCN module is used for extracting high-dimensional spatial features from crystal grain nodes and connection relations thereof; then, an LSTM module is adopted to carry out time sequence modeling on grain stress data which are preprocessed and spliced into a time sequence, and the hidden state of the last time step of the sequence serves as a dynamic feature; and then fusing the features of the two parts element by element, and mapping the fused features into a grain-level stress prediction value through a full connection layer. The stress data predicted for microstructures of different texture types are reversely reconstructed into a three-dimensional visual image which is highly consistent with a crystal plasticity finite element calculation result, the method has a remarkable advantage in calculation speed, and more accurate local information is provided at the same time. The method provides efficient and accurate technical support for microstructure design, alloy performance and preparation process optimization and structural safety evaluation of materials such as titanium alloy.
Owner:INST OF METAL RESEARCH - CHINESE ACAD OF SCI

Irradiation zirconium alloy plasticity limit prediction method based on crystal plasticity finite element

The invention relates to the technical field of nuclear reactor fuel element analysis, in particular to an irradiated zirconium alloy plasticity limit prediction method based on a crystal plasticity finite element, which comprises the following steps: establishing a three-dimensional polycrystalline representative body cell model conforming to the actual grain size of zirconium alloy; based on a crystal plasticity theoretical model, zirconium alloy material parameters are obtained through calculation; boundary conditions and load conditions are determined, finite element calculation is executed in combination with material parameters, and an element stiffness matrix of each increment step is output; assembling the unit stiffness matrix, and obtaining a macroscopic stress-strain matrix of the three-dimensional polycrystal cell model through a homogenization method; and substituting the macroscopic stress-strain matrix into the Rice theoretical criterion, traversing the macroscopic stress-strain matrix of each increment step, and determining the plastic strain meeting the judgment critical condition. According to the method, accurate finite element plastic limit analysis can be carried out on the irradiation material, and the plastic limit strain of the zirconium alloy under the irradiation condition can be accurately judged.
Owner:NUCLEAR POWER INSTITUTE OF CHINA

Method for establishing nonlinear constitutive model of low-temperature marine steel

InactiveCN121959758AImprove predictive reliabilityAchieve physical consistent descriptionGeometric CADMathematical modelsPrincipal stressData set
The invention provides a method for establishing a nonlinear constitutive model of low-temperature marine steel, and relates to the technical field of ships and materials. A heterogeneous time series data set is provided for model construction through multi-type sample multi-axial load tests and full-field strain acquisition; nonlinear mapping of deformation activation energy about temperature and microscopic state variables is established by taking a crystal plasticity theory as a framework, and the defect that a low-temperature dislocation evolution rule cannot be reflected due to the fact that a traditional model solidifies physical parameters into constants is overcome; a damage evolution operator jointly induced by stress triaxial degree and a principal stress threshold is embedded, Bayesian inference is adopted to carry out parameter joint calibration, model dynamic calibration and parameter continuous optimization are realized through a simulation and experiment closed-loop iteration mechanism, and finally a digital design evaluation model capable of being under untested extreme working conditions is produced. And an engineering tool taking physical interpretability and probabilistic safety margin into consideration is provided for the ice-resistant design of the polar region ship.
Owner:NANTONG INST OF TECH

Modeling and analyzing method for metal matrix composite crystal plasticity finite element

The invention discloses a modeling and analysis method for a metal matrix composite crystal plasticity finite element, and particularly relates to the field of metal matrix composites for spaceflight. Comprising the following steps: acquiring EBSD data of a to-be-detected metal-based composite material; identifying a metal matrix phase and a reinforced fiber phase according to the EBSD data; carrying out texture analysis on the to-be-detected metal matrix composite material, and determining grain orientation data; according to the grain orientation data, establishing a finite element model of the to-be-tested metal matrix composite material, and generating a geometric grid; identifying a metal matrix phase and a reinforced fiber phase in the finite element model, and endowing each phase with parameters; according to the crystal plasticity constitutive model, determining the strain of the to-be-measured metal-based composite material; and original crystal plasticity parameters are corrected according to the actually-measured strain and strain, and the metal-based composite material model is obtained. The metal matrix composite model can obtain the grain plastic strain in the plastic deformation process.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Method and system for predicting mechanical properties of laser welded particle reinforced welds of aluminum-lithium alloys

The application discloses a method and system for predicting mechanical properties of laser welded particle reinforced welds of aluminum-lithium alloys, and particularly relates to the field of predicting mechanical properties of laser welded joints. A cross-scale parameter transfer path from first principles to crystal plasticity is established. By constructing a unified high-precision machine learning potential function, the mechanical behavior of complex multi-phase interfaces is accurately quantified, providing a solution for understanding the micro-damage mechanism of the weld. Secondly, by establishing an experiment-driven closed-loop self-correction mechanism, the cumulative error problem introduced by the simplification of models at different scales is effectively solved, and the self-optimization and precision improvement of the prediction model are realized. Finally, a high-confidence digital tool is provided for welding process parameter optimization and new material design, significantly shortening the research and development cycle and reducing the test cost, and having important engineering application value in the field of high-end manufacturing such as aerospace.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Dynamic recrystallization multi-scale simulation method and system coupled with crystal plasticity

The invention provides a dynamic recrystallization deformation structure and performance multi-scale simulation method and system coupled with crystal plasticity, and the method comprises the steps: simulating a metal plastic processing process through macroscopic finite element calculation, updating the state through a macroscopic material constitutive model in the calculation process, recording the historical information related to deformation of each unit, and calculating the deformation of each unit; a microstructure plastic recrystallization model is adopted, microstructure calculation is carried out in combination with deformation historical information, tissues, textures and stress at specified intervals are output, geometric information of a macroscopic finite element is extracted, geometry is reconstructed according to finite element deformation coordinate information, and according to the corresponding tissue, texture and stress information of unit and strain state indexes, the microstructure, texture and stress information of the unit and strain state indexes is calculated. And realizing prediction display of tissue and texture distribution in an overall corresponding deformation state. According to the method, under the metal non-uniform hot working plastic deformation state, the multi-scale simulation method for the structures, textures and mechanical properties of different areas is predicted, and the method has great significance in guiding metal plastic working process design and structure property regulation and control.
Owner:SHANGHAI JIAOTONG UNIV

Fatigue life prediction method based on physical failure mechanism in liquid lead bismuth environment

The invention relates to a fatigue life prediction method based on a physical failure mechanism in a liquid lead bismuth environment, and the method comprises the following steps: building a representative volume element model, and defining elements belonging to a slip band; defining a crystal plasticity constitutive equation; determining parameters in the crystal plasticity constitutive equation; calculating the average shear strain range of the slip band; carrying out a fracture toughness test to obtain specific fracture energy; establishing a fatigue life prediction model based on a physical failure mechanism; carrying out a symmetrically cyclic low-cycle fatigue test on the metal material in a predicted-temperature high-oxygen liquid lead bismuth environment to determine the thickness of an oxide film; and establishing a fatigue life prediction model in the high-oxygen-concentration liquid lead bismuth environment, and predicting the fatigue life of the metal material in the high-oxygen-concentration liquid lead bismuth environment. According to the method, the fatigue life in the liquid lead-bismuth environment can be predicted by carrying out a low-cycle fatigue test for calibrating crystal plasticity constitutive equation parameters in the air at the predicted temperature and a fracture toughness test in the air and liquid lead-bismuth environment.
Owner:TIANJIN UNIV

A method and system for nonlinear decoupling of a triaxial force sensor

The present application relates to the technical field of force sensor, disclose a kind of nonlinear decoupling method and system of triaxial force sensor, comprising: acquisition multi-dimensional original data, and carry out adaptive noise reduction, dynamically select wavelet base, construct filter matrix and obtain denoising signal;Dynamic PINN proxy model is constructed, material parameters and environmental variables are fused, and stiffness matrix is output, online parameter updating mechanism is established, and the optimized parameter calculated is constructed enhanced dynamic compensation matrix;The output stiffness matrix and enhanced dynamic compensation matrix are fused and the main singular value is reserved;Reconstruction obtains reconstructed strain field, establishes multi-physical field coupling model compensation quantum-thermal coupling error, and compensates the lead inductance coupling under high frequency;Multi-scale graph structure is constructed, loss function is reinforced by physical constraint, crystal plasticity hysteresis compensation is carried out, multi-scale features are fused, and the decoupling force value is calculated;Establish intelligent calibration decision, predict drift trend and dynamically adjust calibration cycle.
Owner:HARBIN INST OF TECH (SHENYANG) INTELLIGENT IND TECH CO LTD

An oriented electrical steel cold rolling texture rapid prediction method and system based on crystal plasticity finite element and sequential condition generation type deep learning agent model and a medium

The application discloses a kind of based on crystal plastic finite element and sequence condition generation formula deep learning agent model's oriented electrical steel cold rolling texture fast prediction method, system and medium, with cold rolling process parameter set as input, with ODF slice image as output;Through the crystal plastic finite element model driven by physical mechanism, "process path-ODF" virtual labeling data pair is generated in batch in pre-set cold rolling process design space, and data set is constructed;Then using sequence condition generation formula deep learning agent model realizes the end-to-end nonlinear mapping from cold rolling process path to high-dimensional ODF image, so that the premise of not needing to call crystal plastic finite element model successively, realize the fast prediction, visualization and path regulation of cold rolling texture evolution.This application solves the problem of existing fusion crystal plastic simulation precision advantage and deep learning model high efficient generalization ability, realizes the fast and accurate prediction of cold rolling texture evolution.
Owner:BAOSHAN IRON & STEEL CO LTD +1

A high-efficiency calculation method for gradient nanostructure friction and wear

The application discloses a kind of gradient nanostructure sliding wear high-efficiency calculation method, comprising: obtaining gradient nanostructure grain size parameter and load parameter, determine the material parameter at different depths;Establish size-dependent crystal plasticity constitutive model and dislocation density evolution model and cluster homogenization model;Establish three-dimensional friction contact finite element model, calibrate constitutive model parameters and friction and wear parameters;In three-dimensional friction contact finite element model, calculate the results such as contact pressure, relative slip, cumulative plastic strain, dislocation density;Based on energy dissipation theory, calculate the wear depth increment of each contact node.The application can be coupled in the same calculation framework gradient grain size, crystal plastic deformation, dislocation density evolution, friction contact and surface wear evolution, obtain the wear depth, contact pressure, cumulative plastic strain, dislocation density of gradient nanostructure under reciprocating sliding load, and can be used for comparing the wear resistance under different surface grain size.
Owner:TIANJIN UNIV

Complex component crystal plasticity finite element cross-scale modeling method based on topological decoupling

The invention relates to a topological decoupling-based complex component crystal plasticity finite element cross-scale modeling method, which comprises the following steps of: firstly, carrying out macroscopic finite element grid division on a geometric model of a component to be analyzed to export an isolated grid file, and then establishing an RVE voxel grid based on microstructure source data of a material of the component to be analyzed; calculating the geometric centroid coordinate of each unit after macroscopic finite element grid division, and judging the attribution crystal grain ID of each geometric centroid coordinate in the RVE voxel grid through a centroid mapping algorithm to generate a unit set mapping file; then calculating a rotation matrix for each crystal grain ID based on crystal orientation distribution data, combining the rotation matrix with crystal plasticity constitutive model parameters to generate a physical attribute library file, and finally performing semantic analysis and recombination on an isolated grid file to generate a CPFE cross-scale simulation model. According to the method, macroscopic finite elements and microscopic voxel grids are decoupled, the problem that complex geometric expression precision and microstructure fidelity are difficult to consider at the same time is solved, and CPFE cross-scale accurate modeling of complex components is achieved.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

Method for constructing nuclear power steel hot manufacturing full-process grain evolution model based on high-throughput characterization and data driving

According to the nuclear power steel hot manufacturing full-process grain evolution model construction method based on high-flux characterization and data driving, a sample of high-flux grain configuration is designed, global high-flux microscopic structure characterization is carried out, crystallographic information of mass micro-area structures is obtained, and parameterized expression suitable for describing each grain configuration is given. Through cross-scale multi-physical field modeling of a rigid viscoplastic finite element method and a crystal plasticity finite element method, the distribution rule and quantitative description of deformation energy storage of each micro-area of the large-size nuclear power austenitic steel under different thermal deformation process conditions are explored. And a data driving model of the thermal deformation-deformation energy storage-solid solution grain configuration relation of the austenitic steel for nuclear power is constructed, and an active regulation and control strategy and method for controlling coarse grains / mixed grains of the austenitic steel for nuclear power are formed. The method can provide theoretical and method support for accurate quantitative prediction of nuclear power key part thermal manufacturing full-process grain evolution and active control of abnormal grains.
Owner:YANSHAN UNIV

Spherical tooth tip blade safety evaluation method and system based on data analysis

The application discloses a spherical tooth tip blade safety evaluation method and system based on data analysis, and relates to the technical field of cutting processing.The application comprises the following steps: collecting blade surface morphology, microscopic lattice structure and cutting dynamic load data through a white light interferometer, EBSD and a dynamometer; establishing a macro finite element model and embedding a microscopic crystal plasticity submodel; matching macro and microscopic stress fields, calculating lattice orientation conversion matrix and Schmid factor, and extracting slip system characteristic parameters; determining crack initiation, calculating an extension path in combination with an anisotropy criterion, and reconstructing three-dimensional crack morphology; calculating a cumulative damage factor, dividing three-level safety threshold values, and outputting a visual report and a life prediction value.The application establishes a coupling equation of macro stress field and microscopic crystal orientation, integrates the mechanical response characteristics of a material at different scales, and improves the physical authenticity of crack initiation and extension prediction.
Owner:HAINING YONGFA SHAVERS & SCISSORS CO LTD

Method for quantitatively revealing starting amount of grain size deformation mechanism

The invention discloses a method for quantitatively revealing the starting amount of a grain size deformation mechanism, and belongs to the technical field of finite element simulation of microcosmic plastic deformation and crystal plasticity. According to the method, in-situ / quasi-in-situ electron back scattering diffraction characterization and crystal plasticity finite element simulation are combined, real grain initial orientation distribution and grain shape evolution information are obtained through experiments and introduced into a finite element model, and accurate quantitative analysis of deformation mechanisms such as slippage and twinning is achieved. Compared with a traditional method, the method breaks through the limitation of an experiment in the aspect of quantitative characterization of the starting amount of a grain size deformation mechanism, and meanwhile the problem that a conventional simulation method is large in error under the grain size is solved. Through deep fusion of experiments and simulation, the quantitative analysis precision of the deformation mechanism is remarkably improved, and a powerful technical support is provided for research of the microcosmic plastic deformation mechanism.
Owner:CHONGQING UNIV

Nickel-based single crystal alloy fatigue life forecasting method considering second orientation and recrystallization defect

The invention relates to the technical field of single crystal alloy fatigue life prediction, in particular to a nickel-based single crystal alloy fatigue life prediction method considering second orientation and recrystallization defects. The specific method comprises the following steps: obtaining a plurality of nickel-based single crystal alloys as single crystal alloy samples which have different second orientations and have recrystallization defects partially; establishing a crystal plastic model; acquiring fatigue life and fatigue stress parameters; inputting the fatigue stress parameter into a crystal plastic model to calculate the accumulated plastic shear strain of the dangerous point; 1 / 2 of the product of the cumulative plastic cutting strain and the fatigue load in the crystal plasticity or the cumulative plastic cutting strain is used as a fatigue indication factor; and fitting by taking the fatigue indication factor as a vertical coordinate and the fatigue life as a horizontal coordinate to obtain a fatigue life prediction model. According to the method, the recrystallization defect and the influence of different second orientations are considered, the related fatigue indication factors are introduced to construct the fatigue life prediction model between the fatigue indication factors and the fatigue life, and the accuracy and reliability of the prediction result are improved.
Owner:SUN YAT SEN UNIV

Creep property prediction method of ODS steel under high temperature and high irradiation conditions

The invention relates to a method for predicting the creep performance of oxide dispersion strengthened (ODS) steel under high temperature and high irradiation conditions. A complex crystal plasticity constitutive model is developed to accurately predict the performance of ODS steel in terms of irradiation hardening and creep behavior, which incorporates the spatial distribution of voids and oxides. This developed model is highly consistent with experimental data at different temperatures and irradiation doses, demonstrating its strong robustness. As the irradiation dose increases, the yield stress of irradiated ODS steel also increases. The yield strength of ODS steel shows a linear relationship with the irradiation dose, which initially increases with the increase of irradiation dose and then decreases. The void size steadily increases, while the void spacing initially decreases and then increases. Therefore, the void hardening effect gradually weakens after the initial enhancement. In contrast, as the irradiation temperature increases, the yield strength decreases due to the expansion of the void spacing at higher temperatures. The creep rate of irradiated ODS steel is nonlinearly related to the irradiation dose. ODS steel irradiated at low or high doses has relatively poor creep performance and exhibits a higher creep rate under low applied stress. In contrast, at moderate doses, the creep performance is better due to the small number of irradiated voids and high strength of oxide particles. And spherical voids exhibit better creep resistance, and the void spacing has a more significant impact on the creep performance than the void size. At low and high doses, the creep performance decreases as the irradiation temperature increases, and in addition, at lower doses, the effect of irradiation temperature on creep performance is not as significant as at higher doses. This invention provides an efficient theoretical method for accurately evaluating the irradiation performance of ODS steel under complex environments.
Owner:HUNAN UNIV

Method for establishing plastic constitutive model of additive manufacturing metal crystal and determining parameters of plastic constitutive model

The invention discloses an additive manufacturing metal crystal plastic constitutive model establishment and parameter determination method, which can realize high-precision physical mechanism driven determination of additive manufacturing metal crystal plastic constitutive model parameters based on a synchronous X-ray diffraction technology and EBSD-RVE modeling. And the description accuracy of the model on the microstructure and the deformation behavior of the material is obviously improved.
Owner:TSINGHUA UNIVERSITY

A method for establishing and determining parameters of a metal crystal plasticity constitutive model for additive manufacturing

The application discloses a method for establishing and determining a metal crystal plasticity constitutive model of additive manufacturing, which can realize high-precision and physical mechanism driven determination of parameters of the metal crystal plasticity constitutive model of additive manufacturing based on a simultaneous X-ray diffraction technology and EBSD-RVE modeling, and significantly improves the description accuracy of the model on microstructure and deformation behavior of materials.
Owner:TSINGHUA UNIVERSITY