Dynamic recrystallization behavior and mechanism of Fe–Cr–Ni–Mn–Mo–N low magnetic stainless steel during hot deformation

A newly designed Fe–Cr–Ni–Mn–Mo–N low magnetic stainless steel was tested based on hot deformation at 950–1150 °C and 0.01–10 s−1 strain rate conditions. The flow curves of the hot deformation process are of dynamic recrystallization type, the softening mechanism is mainly dynamic recrystallization. Complete dynamic recrystallization occurs when the deformation temperature is higher than 1100 °C. The microstructure evolution of the dynamic recrystallization process is characterized by electric backscatter diffraction. The Avrami kinetics of low magnetic stainless steel under different deformation conditions are established to effectively predict the dynamic recrystallization behavior during hot deformation. Through microstructure analysis, it is clarified that the discontinuous dynamic recrystallization formed by the high angle grain boundaries bulging and migration is the dominant dynamic recrystallization mechanism of low magnetic stainless steel. The continuous dynamic recrystallization formed by the sub-grains rotation and dislocations absorption is the auxiliary mechanism. The characteristics of dynamic recrystallization nucleation, grain growth, and microstructure evolution of the low magnetic stainless steel during hot deformation are described.