Microstructural evolution of adiabatic shear bands in TA2

Adiabatic shear localization is an important failure mechanism in structural impact. In order to characterize the adiabatic shear susceptivity of hexagonal close-packed (HCP) metal materials, the formation and evolution of adiabatic shear bands at high strain rate deformation of pure titanium TA2 were investigated using Hopkinson bar system. Microstructural characterization of shear bands was performed using scanning microscopy and high-resolution transmission electron microscopy. Results show that the adiabatic shear bands are formed in the ligament on samples. No evidence of transition from α-Ti to another phase within the adiabatic shear bands can be found. The microstructure of adiabatic shear bands is composed of fine recrystallized particles. It is shown that the presence of recrystallization in TA2 adiabatic shear bands can be predicted by a progressive subgrain misorientation (PrisM) recrystallization model.