Dynamic mechanical properties in relation to adiabatic shear band formation in titanium alloy-Ti17

A Split-Hopkinson Pressure Bar system was used to determine the dynamic mechanical properties in relation to the formation of adiabatic shear bands in titanium alloy-Ti17. Cylindrical and conical frustum specimens were impacted between the incident and transmitted bars. The experimental results showed that the dynamic yield stress (σyd) and impact strength (σbd) were both higher than the corresponding static values, and the failure was sensitive to the strain rate, but insensitive to the applied stress level. The critical strain rate for failure was ε̇c=2000 s−1. Microscopic examinations revealed that the break of specimen frequently occurred along the shear band. A hemicyclic shear band appeared on the transverse section of the conical frustum, while a straight shear band developed at the location of maximum shear stress and propagated along the trace of the maximum shear stress, which was determined by the analysis of the stress distribution.