Abstract:In the present work, compressive properties and deformation modes of binary Ti-16V alloy have been investigated during dynamic compressive tests performed on split Hopkinson pressure bar. For metastable Ti-16V alloy, the flow stress and strain hardening rate were both independent of the loading strain rate within the strain rate range (1000~3700 s-1) in our experiments. According to the optical microstructure evolution, the critical instability strain rate was confirmed to be about 3000 s-1. Multiple deformation modes including {332}<113> type mechanical twinning and stress induced ω phase transformation were identified by electron backscatter diffraction and transmission electron microscopy. With the help of Schmid factor values calculated in a spherical coordinate system, the dynamic twinning behavior of Ti-16V alloy was analyzed and the critical Schmid factor was proved to be a key parameter determining the activation of twinning behavior. Combining the critical Schmid factor value and true stress, the critical resolved shear stress range of {332}<113> type twinning was calculated to be 334~338 MPa.