Overcoming plasticity reduction in a severely deformed nano-grained metastable alloy

Abstract

Most bulk metallic materials reveal an increased strength but a loss of ductility after cold deformation, a phenomenon known as the strength–ductility trade-off. In this study, we propose a strategy to overcome this problem by introducing a high density of crystalline defects into a Fe-based metastable alloy by refining grains to a nanometer scale. This procedure effectively enhances the kinetics and reduces the driving force for transformation-induced plasticity (TRIP). Consequently, the TRIP effect originally occurring at cryogenic temperature in the studied alloy becomes active at ambient conditions, contributing to a strength–ductility synergy and overcoming cold working induced sacrifice of ductility.

Keywords

• Metastable alloys
• transformation-induced plasticity
• nano grains
• mechanical properties