On the grain size dependent working hardening behaviors of severe plastic deformation processed metals

Based on our analysis, the grain size effect in the most widely used models such as the Kocks-Mecking-Estrin (KME) model cannot account for the work hardening behaviors of nano-crystalline or ultrafine-crystalline metals processed by severe plastic deformation (SPD). By considering the material's initial state, this study provides a consistent interpretation of their work hardening behaviors in terms of the evolution of microstructural features and the mechanical properties. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.