Abstract:The time-dependent springback and anelastic behavior of TC4 titanium alloy were investigated as a function of time, prescribed strain and loading strain rate by universal testing machine. In order to infer its basis, the microstructures of samples under different loading conditions were examined by optical microscope(OM) and transmission electron microscope(TEM). The results reveal that the absolute values of time-dependent springback strain(TDSS) accumulated in 10h both presented exponential growth, as the prescribed strain and loading strain rate went up. The OM and TEM results show that the evolutions of “streamline” microstructure, dislocation pile-up, and deformation twin had positive correlation with the change law of TDSS.