A Novel Multiphase Stainless Steel with Ultra-Low Yield Ratio and High Ductility

This study focuses on developing a novel multiphase stainless steel with enhanced ductility and an ultralow yield ratio achieved through solid-solution treatment. The steel exhibits remarkable mechanical properties: a tensile strength of approximately 1114 MPa, an ultralow yield ratio of 0.36, exceptional uniform elongation of approximately 17.48%, and total elongation of approximately 21.73%. The remarkable ductility of the steel can be attributed to the transformation-induced plasticity (TRIP) effect observed in the retained austenite, while its exceptional strength results from the combined effects of TRIP and the martensite phase.