Coupled simulation of microstructural formation and deformation behavior of ferrite-pearlite steel by phase-field method and homogenization method

A coupled simulation by the phase-field (PF) method and the finite element method based on the homogenization theory (FEH) is developed to predict the microstructure formations and mechanical properties of ferrite-pearlite steels. The formation of the α phase during the isothermal γ→α transformation is simulated by the PF method. Furthermore, the FEH analysis is performed to clarify the effects of the predicted microstructure on the deformation behavior of the steels. In order to link to the FEH analysis, the microstructure in the steel is described by the representative volume element (RVE) based on the results of the PF simulation. The results reveal that although the macroscopic stress-strain relationship is mainly characterized by the volume fraction of the constituent phase, the localization of plastic strain is reduced due to the fine-grained α phase. This numerical model provides a systematic way of predicting the mechanical properties of steel depending on the microstructure.