A grain scale approach for modeling steady-state discontinuous dynamic recrystallization

✍ Scribed by F. Montheillet; O. Lurdos; G. Damamme

• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 535 KB
• Volume: 57
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/j.actamat.2008.11.044

✦ Synopsis

Discontinuous dynamic recrystallization (DDRX) generally occurs in low-stacking-fault-energy metals. New grains nucleate and grow at the expense of the strain-hardened older grains. A steady-state flow stress independent of initial conditions is experimentally observed. A general model is proposed to describe these phenomena. While the transient behavior can be addressed only numerically, a steady state is described in detail by closed-form relationships. The approach includes strain hardening and dynamic recovery, nucleation, growth and shrinkage of grains. Furthermore, the strain-hardening equation can be supplemented to account for the effect of boundary-migration-induced softening (BMIS). The present paper first states the general equations of the model; some simple strainhardening laws neglecting BMIS are then discussed. Finally, a method for evaluating the material parameters is described and illustrated by the example of 304L stainless steel.