Modeling of recrystallization through the integration of disorientation and nucleation mechanisms: application to ferritic stainless steel

The mechanisms of continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX) are usually treated as distinct in the literature. In this study, we propose a unified grain-scale framework that integrates both mechanisms. It combines subgrain boundary formation and misorientation, following the model originally proposed by Gourdet et al., and incorporates nucleation mechanisms through a thermodynamic formulation. The framework was evaluated at 900 C for a true strain of =0.6 in a niobium-free ferritic stainless steel. Additional tests at =0.3 and =0.6 characterized the dynamic regime, followed by holding experiments to assess static evolution. Model predictions were validated against grain size distributions, recrystallized fractions, misorientation distributions, and the decay of subgrain boundary density. Overall, the model demonstrates that CDRX and DDRX can be coupled within a simplified framework, providing a consistent description of both dynamic and static recrystallization regimes. • Unified DDRX–CDRX recrystallization model. • Substructure-driven nucleation criterion. • Calibration and validation on ferritic stainless steel. • Mean-field approach with local resolution.