Analysis of energy absorption of adiabatic shear plugging in thermoviscoplastic targets

Abstract

A mechanical model, based on the theory of adiabatic shear instability and fracture of thermoviscoplastic materials, is proposed to analyse the energy absorption of plugging. An important relationship between energy absorption and initial impact velocity is obtained. When the initial velocity is slightly greater than the critical impact velocity, the energy absorption decreases with increasing initial velocity; however, the energy absorption increases for initial velocity greater than the critical impact velocity. This analytical result is the same as that observed experimentally. This phenomena is explained with the adiabatic shear instability and fracture criterion controlled by both the strain and strain-rate.