Multi-scale modeling method for multiphase alloy

The invention discloses a multi-scale modeling method for a multi-phase alloy, and the method comprises the steps: building atomic scale models of matrix phase, precipitation phase and impurity phase polycrystalline cells; using DREAM.3D software to import EBSD data to generate a multiphase microstructure, and exporting unit data to generate an Abaqus input file; constructing crystal plastic material parameters by using MATLAB, and writing the crystal plastic material parameters into an Abaqus input file according to a crystal grain ID sequence to generate a matrix phase and a precipitated phase representative volume element RVE; according to the method, impurity phase lattice material parameters are modified in batches by using a Python script in Abaqus, so that a crystal plasticity finite element microstructure model of the multiphase alloy is constructed, then a macroscopic finite element global model of a multiphase alloy part is established, and multi-scale modeling is realized by using an FE-RVE microme