A unified mesoscale framework for predicting the orientation-dependent substructure evolution in FCC metals

Abstract

Numerous studies indicate that the type of dislocation substructure in FCC metals depends on the crystal orientation. However, a predictive model is still lacking in the literature. This work aims to establish a mesoscale modeling framework capable of predicting the orientation-dependent substructure in polycrystalline aluminum. A physics-based crystal plasticity (CP) model was employed for this purpose. Based on the CP simulation results, we formulate various descriptor functions that could potentially characterize the type of dislocation substructure. The function that accounts for both slip activity and cross-slip-based dynamic recovery effectively captures the orientation-dependent substructure evolution under tension and plane strain compression. Furthermore, it demonstrates the ability to predict intragranular heterogeneity and the effect of deformation temperature on the substructure evolution. Therefore, the CP model in conjunction with the descriptor function constitutes a mesoscale framework that can enhance the prediction of substructure morphology and optimize material properties sensitive to these substructures.