"Two-Dimensional Grain Growth Kinetics of Polycrystalline Materials" 

Zijun Su, MSE PhD Candidate 

Advisor: Professor R. Edwin García

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ABSTRACT

Grain growth is a fundamental microstructure evolution process in polycrystalline materials, historically known to be driven by the reduction of interfacial energy. This coarsening process reveals the increase in average grain size and the self-similarity of the grain size distribution over time. Understanding the grain growth and coarsening kinetics is essential for predicting material behavior and designing modern technology for applications such as batteries, austenitic stainless steels, and solar cells. This prelim reviews existing two dimensional grain growth models based on sharp interface and diffuse interface, phase field, frameworks. Sharp interface models are based on the linear relationship between grain boundary velocity and its driving force, leading to the well-known N-6 rule, the vertex model approach, the empirical scaling rule, Mullins’ statistical model, and grain size distribution modeling approached by Brakke. In contrast, phase field approach is a powerful class of diffuse interface methods, including multi phase field model which describes each grain independently, Kobayashi–Warren–Carter (KWC) model which uses a single orientation to describe different grains, the Staublin-Mukherjee-Warren-Voorhees (SMWV) model which uses a single well potential to describe the volumetric free energy density with an orientation field. Finally, the relationship between sharp interface and phase field models is discussed, to make it quantitatively consistent with experimentally measurable parameters.