Aging Precipitation Behaviour of Cr-Mn-N Austenitic Stainless Steels

This work is focused on the austenite decomposition in Cr-Mn-N austenitic stainless steels. The experimental steels was solution heat treated (1100°C/30 min. followed by water quenching) and then annealed in the temperature range from 650 to 900°C for holding time 5 min. to 100 hours for the study of precipitation. The precipitation behaviour during isothermal aging was investigated using light optical microscopy, transmission electron microscopy, selected area diffraction and energy-dispersive X-ray spectroscopy. The results show that the phase composition of the precipitates depends on the chemical composition of the experimental steel. The critical temperature of precipitation is 825°C with the corresponding time 100 s.