Dynamic mechanical behaviour induced by adiabatic temperature rise of Fe–Mn–Al–C steel

Abstract

The dynamic mechanical behaviour induced by adiabatic temperature rise of Fe–Mn–Al–C twinning-induced plasticity steel was investigated via the dynamic tensile test and a dynamic constitutive model. The twinning kinetics and recovery factor, which are all rate- and temperature-dependent, were introduced to describe the stress–strain relationships. Verified by experimental flow stress and twin volume fraction, simulated results are in good agreement with experimental ones. Because of the more active twinning that contributing plasticity at a higher strain rate, the decreasing plasticity from dislocation slip induces a retardation of dislocation multiplication and is responsible for the low strain hardening rate. In the later stage, the adiabatic heating promotes dislocation annihilation by enhanced dynamic recovery, resulting in the negative rate-dependent hardening.