Mechanical behavior of a stainless steel material at elevated temperatures and high strain rates

Dynamic compressive mechanical behavior of a stainless steel material was studied at elevated temperatures and high strain ratesby using split Hopkinson pressure bar (SHPB), which was installed with heating and synchro assembly system. The tests were carried out at loading rates ranging from 1100 to 16000 s-1 and temperatures from 20 to 800°C. The strain rate and temperature sensitivities of flow stress are analyzed. The intrinsic mechanism is discussed according to the thermally activated dislocation motion theory. The results show that the material has evident heat softening effect and strain rate hardening effect. And both the strain rate and temperature sensitivities of the material are increased at higher temperatures.