Generalized Phase Field Model for Computer Simulation of Grain Growth in Anisotropic Systems

TL;DR

This paper introduces a generalized phase field model to simulate grain growth considering anisotropic boundary energy and mobility, revealing their distinct impacts on grain morphology and growth dynamics.

Contribution

The study develops and validates a new phase field model that incorporates boundary inclination and misorientation, advancing understanding of anisotropic grain growth.

Findings

Grain boundary energy anisotropy strongly influences grain shape.

Mobility anisotropy leads to non-self-similar evolution and shape anisotropy.

Average grain area grows linearly over time regardless of anisotropy.

Abstract

We study the dynamics and morphology of grain growth with anisotropic energy and mobility of grain boundaries using a generalized phase field model. In contrast to previous studies, both inclination and misorientation of the boundaries are considered. The model is first validated against exact analytical solutions for the classical problem of an island grain embedded in an infinite matrix. It is found that grain boundary energy anisotropy has a much stronger effect on grain shape than that of mobility anisotropy. In a polycrystalline system with mobility anisotropy, we find that the system evolves in a non-self-similar manner and grain shape anisotropy develops. However, the average area of the grains grows linearly with time, as in an isotropic system.