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arXiv · 2005.07230

A mean-field model of static recrystallization considering orientation spreads and their time-evolution

Abstract

In this paper, we develop a mean-field model for simulating the microstructure evolution of crystalline materials during static recrystallization. The model considers a population of individual cells (i.e. grains and subgrains) growing in a homogeneous medium representing the average microstructure properties. The average boundary properties of the individual cells and of the medium, required to compute growth rates, are estimated statistically as a function of the microstructure topology and of the distribution of crystallographic orientations. Recrystallized grains arise from the competitive growth between cells. After a presentation of the algorithm, the model is compared to full-field simulations of recrystallization performed with a 2D Vertex model. It is shown that the mean-field model predicts accurately the evolution of boundary properties with time, as well as several recrystallization parameters including kinetics and grain orientations. The results allow one to investigate the role the orientation spread on the determination of boundary properties, the formation of recrystallized grains and recrystallization kinetics. The model can be used with experimentally obtained inputs to investigate the relationship between deformation and recrystallization microstructures.

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Arthur Després, Michael Greenwood, Chad Sinclair. 2020-05-14. A mean-field model of static recrystallization considering orientation spreads and their time-evolution. https://arxiv.org/abs/2005.07230

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