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

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.
High-density crystalline defects were introduced into a metastable alloy, leading to an increase in TRIP temperature. This helps to overcome the strength–ductility trade-off in the severely plastic-deformed alloys at ambient conditions.