Abstract
In this study, a multi-phase-field (MPF) model describing evolution of twin microstructure with two or more variants of twin is developed. Three kinds of free energy namely elastic energy, barrier energy and interfacial energy are considered. In order to introduce the strong anisotropy of interfacial energy, nonlinear form of its functional is adopted. The MPF model is coupled with dislocation-based crystal plasticity model, which is developed previously by the authors, via order parameter and resolved shear stress acting on twin system that plays a role of driving force of twin microstructure development. Using the above model, a uniaxial tensile FE analysis on pure magnesium including two variants of twin is carried out. From the result of the present analysis, compression stress considered to be occurred by twin shear is seen at the triple junction among matrix and two twins. In addition, basal slip and accumulation of dislocation is observed in the vicinity of twin interface, especially at the triple junction.
