Transition of 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 transitional work hardening behaviors of nano-crystalline or ultrafine-crystalline metals processed by severe plastic deformation (SPD). Alternatively, from the perspective of material's initial state, this study provides a consistent interpretation of their work hardening behaviors in terms of the microstructural features and the mechanical properties.