Dislocation Mechanics of Extremely High Rate Deformations

Abstract

High strain rate simulations were performed using the multiscale dislocation dynamic plasticity (MDDP) method to calculate different rise times and load durations in mimicking high deformation rate shock as compared with isentropic (ramp) testing of α-iron and tantalum materials. Smaller differences than expected were found between the two loading behaviors and attributed to the shock loading being relatively weak. Comparisons were also made with thermal activation strain rate analysis (TASRA), phonon drag and dislocation generation predictions for the behaviors.