Titanium and molybdenum content in supermartensitic stainless steel

The supermartensitic stainless steels (SMSS) must be developed considering a balance between strength and toughness that are achieved by controlling the chemical compositions and heat treatment. In this paper, the results of detailed investigations on 12.50 Cr-5.40 Ni-2.10 Mo-0.13 Ti SMSS composition were obtained after the SMSS was put in a vacuum furnace and subsequently hot rolled and heat-treated. A very fine microstructure of martensite matrix with nanometer size particles of titanium carbonitride (Ti(C, N)-70 nm) was selected after quenching and tempering. Such microstructure reasonably showed an improved mechanical property values: 28 RC hardness, 804 MPa tensile strength, 764 MPa yield strength, 23.7% elongation and 256 J impact energy.