Effect of Strain Rate on Mechanical Properties of Fe-23Mn-2Al-0.2C TWIP Steel

The effect of strain rate on the mechanical properties has been investigated for a solid-solution treated TWIP steel Fe-23Mn-2AI-0.2C.The results show that the strain rate in the range of 2.97×10~(-4)-1.49×10~(-1)s~(-1) has no obvious influence on yield strength.However,tensile strength was slightly decreased and elongation evidently decreased as the strain rate was increased.Deformation behavior with three stages was observed as the change of strain hardening rate for low strain rate.While for high strain rate,there exist only two stages in the deformation behavior with respect to the strain hardening rate and true strain.Strain hardening exponent of this steel increases with increasing true strain.High density deformation twins forms during the deformation for different strain rates,and the width of deformation twin lath decreases as the strain rate increases.