Alloy Design and Phase Transformation of Nitrogen-Alloyed Metastable Austenitic Stainless Steels

摘要

By the aid of Thermo-Calc commercial software, new type of metastable austenitic Cr-Mn-N stainless steels (MASSs in short), with no or a small amount of nickel, were developed. Phase transformation in MASSs was studied by ferrite scope and X-ray diffraction (XRD). The results show that the studied steels with Ni less than 2% or little N could have the outstanding metastability because α'-martensite can be easily induced during deformation at room temperature. When nickel content is more than 3% , the microstructures in steels are quite stable at room temperature so that no ε-martensite could be found even after 50% deformation.