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

Patent metadata

Field	Value
Publication number	US-2025229365-A1
Application number	US-202519023632-A
Country	US
Kind code	A1
Filing date	Jan 16, 2025
Priority date	Jan 16, 2024
Publication date	Jul 17, 2025
Grant date	—

Abstract

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.

First claim

What is claimed is:

1 . A full-automatic full-process modeling method of the crystal plasticity finite element model for laser welding weld, characterized by combining MATLAB software and ABAQUS finite element analysis software, using METX toolbox to process EBSD microstructure data of laser welding welds, and constructing and verifying the crystal plasticity finite element model; Firstly, EBSD data is denoised, and then grain information is extracted for model building, then, writing and executing scripts in MATLAB to automatically create ABAQUS model, importing grain data to generate INP file, and assigning material properties, Finally, outputting grain orientation information is by running a simulation, and extracting a stress-strain curve of simulation results, the full-process is fully automated from the EBSD data to crystal plasticity finite element model;
which comprises the following steps: Step 1 : using MATLAB to call METX toolbox to import EBSD data for laser welding welds, and creating EBSD data set in MATLAB workspace; Step 2 : using grain segmentation, confidence index filtering, small grain filtering and other methods to establish a grain set of original EBSD data, removing a grain in a very small size, and reduce a noise of original laser welding weld EBSD data; Step 3 : extracting the EBSD data after noise reduction, comprising a grain number, an equivalent diameter, an euler angle of grain orientation, grain pixel coordinates, a grain set and other data of each grain, drawing a grain distribution map after noise reduction, and comparing with original laser welding weld EBSD grain distribution map; Step 4 : extracting a length and a width of original EBSD scan data through MATLAB, calculating a step size of a single pixel of EBSD scan data for laser welding welds, and converting a unit from um to mm; Step 5 : entering a mesh size of crystal plasticity finite element model of the laser welding weld, an initial analysis step length, the minimum analysis step length and the maximum analysis step length in ABAQUS analysis step; Step 6 : writing and generating py files to create an initial model of ABAQUS through MATLAB; executing the py file by calling PYTHON through MATLAB to automatically generate the INP file of the initial model; Step 7 : reading each node data and unit data of the initial model through MATLAB, and generating a data file of a node and a unit set of each grain in ABAQUS according to a location of each grain and a pixel value occupied by each grain, and writing into the INP file of the initial model, generating the INP file of the crystal plasticity finite element model, including the grain structure distribution of laser welding weld; Step 8 : calling ABAQUS GUI interface through MATLAB to import the INP file to verify a consistency of crystal plasticity finite element model with grain structure distribution of laser welding weld and original laser welding weld microstructure distribution; The pixel gray level modulation structure based on phase change materials, is characterized by comprising n multi-layer phase change unit arrays in each sub-pixel, an upper all-dielectric filter structure, an all-dielectric intermediate cavity, a lower all-dielectric filter structure and a crossbar control structure; Step 9 : using MATLAB to call METX toolbox to draw a polar figure of the EBSD data of the original laser welding weld and a polar figure of the grain set after noise reduction, and verifying whether the grain set established is consistent with the original EBSD data; Step 10 : converting a grain Euler angle into a radian value, and using MATLAB to output the PYTHON file that assigns material properties to each grain, wherein the material property assigning code comprises three main parts: automatically reading a grain Euler angle radian value, converting radian value to Miller index, and assigning a grain size effect; Step 11 : using MATLAB to call ABAQUS to perform PYTHON for material property assignment, assigning material properties to each grain, and generating the INP file of the crystal plasticity finite element model, including the grain structure distribution of laser welding weld; Step 12 : generating an empty dat file through MATLAB to write an orientation information of each grain in the final crystal plasticity finite element model output by ABAQUS; Step 13 : calling ABAQUS through MATLAB to run the final generated INP file, and calling a subroutine of crystal plasticity finite element simulation to output the orientation information of each grain in the final generated crystal plasticity finite element model; calling METX to draw a polar figure of each grain in the final output, and comparing with the polar figure generated in step 8 ; Step 14 : writing the PYTHON file to extract a stress-strain curve of crystal plasticity finite element simulation through MATLAB, and calling ABAQUS to execute the PYTHON file through MATLAB to obtain the stress-strain curve of crystal plasticity finite element simulation; wherein the data set comprises important information such as a grain type, a grain ID, a grain orientation, a phase sequence, and a grain rotation.

2 . The full-automatic full-process modeling method of the crystal plasticity finite element model for laser welding weld according to claim 1 , characterized in that a formula for grain segmentation, confidence index filtering, small grain filtering is:

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wherein a grain rotation is expressed as R1 and R2, and Δθ is an orientation angle difference between two points; If Δθ>angle, two points are considered to belong to different grains;

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Assignees

• Univ Huazhong Science Tech

Inventors

• Geng Shaoning
• Jiang Ping
• Song Minjie
• Shu Leshi

Classifications

• G06F2111/10

  Numerical modelling · CPC title

• G06F2119/10

  Noise analysis or noise optimisation · CPC title

• B23K26/21

  by welding · CPC title

• B23K31/12 Primary

  relating to investigating the properties, e.g. the weldability, of materials · CPC title

• G06F30/23 Primary

  using finite element methods [FEM] or finite difference methods [FDM] · CPC title