A semitopological mean-field model of discontinuous dynamic recrystallization: Toward a correct and rapid prediction of grain-size distribution

Abstract : Some mean-field models are currently available for discontinuous dynamic recrystallization (DDRX). They offer an affordable way to predict the variation of averages altered by DDRX as flow stress, grain size and recrystallized fraction. They predict also a grain-size distribution, but it appears unrealistic, at least if a deterministic equation governs the migration of grain boundaries. The present paper exposes an extension to mean-field models which introduces some topological and stochastic features in the migration equation. This extension aims to bridge the gap between mean- and full-field models. It allows predicting realistic distributions of grain size by keeping the simplicity of mean-field approaches. The results obtained are consistent with experimental data on an 18% Cr–11% Ni stainless steel.