The influence of tempering temperature on the reversed austenite formation and tensile properties in Fe–13%Cr–4%Ni–Mo low carbon martensite stainless steels

The influence of tempering temperature on the reversed austenite formation and tensile properties are investigated in Fe–13%Cr–4%Ni–Mo low carbon martensite stainless steel in the temperature range of 550–950 °C. It is found that at the temperatures below 680 °C, the reversed austenite formation occurs by diffusion. Amount of the reversed austenite is determined by the tempering temperature and the holding time. The segregation of Ni is the main reason for the stability of the reversed austenite. When the temperatures are above 680 °C, the reversed austenite formation proceeds by diffusionless. The reversed austenite will transform back to martensite after cooled to room temperature. The tensile properties are most strongly influenced by the amount of the reversed austenite obtained at room temperature. The excellent combination of good strength and ductility is at 610 °C.