Abstract:Due to accurately understand the rate-temperature’s effect on the dynamic mechanical behavior of NiTi shape memory alloy(SMA), a split Hopkinson pressure bar(SHPB) apparatus and a static material testing system are utilized to perform the quasi-static uniaxial tension tests under different temperatures and the dynamic compression tests subjected to various strain rates in this paper. The experimental results show the strain rate strengthening effect of NiTi alloy, and its stress-strain responses show the double elastic stage and double nonlinear deformation stage. The initial phase transformation stress, the end phase transformation stress and dislocation yield stress increase obviously with increasing strain rate. But the elastic modulus of the parent phase and martensitic phase change little. The results of uniaxial tension tests under different temperatures reveal that the yield stress and elastic modulus of NiTi alloy increase linearly with temperature and then decrease linearly. And the phase transformation hardening rate in these two temperature regions varies significantly.