Capturing of the propagating processes of adiabatic shear band in Ti-6Al-4V alloys under dynamic compression

In the present investigation, the dynamic compression properties and the sensitivity of the formation of adiabatic shear band in the Ti-6Al-4V alloyshaving equiaxed and bimodalmicrostructures were studied. The stop-ring technology traditionally used on the hat-shaped specimen was introduced to the compression experiments to control the engineering strain of the cylindrical specimen. The loading time (t(i)), the critical strain (epsilon(i)) and the localization energy (U-loc) at which adiabatic shear band initiates were differentiated. The loading time (t(i)), the critical strain (epsilon(i)) and the localization energy (U-loc) analyzed were found to be useful points in decoupling the homogenous plastic deformation and the adiabatic shear banding behavior in the dynamic deformation and fracture behavior of the investigated Ti-6Al-4V alloys. The loading time (t(i)), the critical strain (epsilon(i)) and the localization energy (U-loc) were also chosen to quantitatively evaluate the sensitivity of the formation of adiabatic shear band in Ti-6Al-4V alloys having bimodal microstructures with identical primary equiaxed a and similar volume fraction of the transformed 13 matrix. The bimodal microstructure BA with the thickest a lamellar in the transformed 13 matrix demonstrated the lowest possibility of the formation of adiabatic shear band. (C) 2016 Elsevier B.V. All rights reserved.