Strain-induced martensite formation and mechanical properties of a low-Ni N-containing Cr–Mn austenitic stainless steel

Low-Ni N-containing Cr–Mn austenitic stainless steels are promising candidates for structural and biomedical applications. In the present work, for the first time, the strain-induced martensitic transformation and mechanical properties of the low-Ni N-containing Cr–Mn X5CrMnN17-8 alloy were investigated and compared with the AISI 304 and 20l stainless steel grades. It was revealed that the X5CrMnN17-8 alloy has a low stacking fault energy, utilizes the strengthening effect of nitrogen alloying, and exhibits a controlled and desirable kinetics of α′-martensite formation to maintain the transformation-induced plasticity (TRIP) effect up to higher strains. Accordingly, the X5CrMnN17-8 alloy exhibited superior strength-ductility synergy compared to the competing stainless steels with similar grain size.