An investigation of dynamic mechanical behaviour of Ti6Al4V titanium alloy at room temperature

State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China

Abstract

To study the high strain rate shear behaviour of Ti6Al4V titanium alloy, a series of dynamic compression experiments has been performed by split Hopkinson pressure bar (SHPB) using Flat Hat-shaped specimen at room temperature. Macro true shear stress-true strain curves were obtained under different strain rate loading conditions at room temperature. The effects of strain hardening and strain rate hardening on the dynamic mechanical properties of Ti6Al4V titanium alloy were discussed. Results indicate that a) The higher the strain rate, the higher the flow stress, therefore, the material has obvious strain rate hardening effect, b) It is ductile failure for Ti6Al4V titanium alloy under quasi-static loading condition, c) For dynamical tests, the values for true shear stress increase with increasing true strain till the maximum true shear stress, on the contrary, the values for true shear stress decrease with increasing the true strain after the maximum true shear stress and d) The flow stress increases with increasing the true strain under quasi-static loading condition during the plastic deformation.