A phase field model of the effects of dislocation microstructure on grain boundary motion during recrystallization

TL;DR

This paper introduces a phase field model that simulates how heterogeneous dislocation microstructures influence grain boundary motion during recrystallization, providing insights into defect-driven microstructure evolution.

Contribution

The study develops a novel phase field model capturing dislocation microstructure heterogeneity and its impact on grain boundary dynamics during recrystallization.

Findings

Model reproduces multiscale dislocation features.

Dislocation heterogeneity significantly affects boundary motion.

Results align with experimental observations.

Abstract

The internal energy associated with the defect microstructure of strongly deformed crystals provides an important driving force for grain boundary motion during recrystallization. Typical dislocation microstructures are strongly heterogeneous and this heterogeneity affects the motion of recrystallization boundaries. In this study, a phase field model for microstructure evolution encompassing the evolution of both dislocation densities and grain order parameters is formulated. The model is employed to generate typical dislocation microstructures exhibiting multiscale features such as incidental and geometrically necessary dislocation walls. It is then used to study the motion of recrystallization boundaries in the associated complex defect energy 'landscape'. Results are compared to experimental observations.