Computational Construction of Phase Diagram for Cr–Mn–N Steel with a Variable Manganese Concentration

Using the THERMOCALC software package, phase state calculations in the temperature range of 500–1600°C have been performed for eleven compositions of chromium-manganese stainless steels with a manganese concentration ranging from 0 to 20% and with the limiting equilibrium nitrogen concentration corresponding to each composition. The results have been used for plotting a phase diagram making it possible to evaluate the effect of manganese exerted on the extent with respect to the temperature and manganese concentration of the domains of existence of austenite, ferrite, chromium nitride, carbides and σ phase affecting the processing and operational properties of nitrogen-alloyed corrosion-resistant steels.