Mechanical behavior and microstructure evolution during steady-state dynamic recrystallization in the austenitic steel 800H

Investigations of steady-state dynamic recrystallization (DRX) were carried out on an austenitic steel alloy 800H. The influence of strain rate and temperature on the mechanical behavior, microstructure development and texture evolution were analyzed. Strain rate and temperature change experiments during steady-state deformation revealed characteristic interdependencies of flow stress, hardening rate, and grain size. The grain size sensitivity of the flow stress was found to scale with the characteristic length scale of the deformed structure. Based on these observations a new model is proposed that relates the process of DRX to an interaction of mobile grain boundaries with deformation-induced subboundaries.