A systematic investigation was made of dislocation motion, dislocation interactions, and the collective behaviour of dislocations during high strain-rate deformation. Based upon the results of 3-dimensional dislocation dynamics simulations, it was found that using the accurate full-dynamics equation of motion (i.e. including inertial effects) significantly changed the predictions of microstructural evolution and the macroscopic response, as compared with the commonly used over-damped equation of motion (i.e. with no inertial effects); especially at high strain rates (103 to 106/s). Although it was found that inertial effects could not be neglected, the net velocities were not high enough to make so-called relativistic effects important. Results were also presented concerning the effects of high strain rates upon single-crystal deformation. These showed good agreement with experimental trends, including an increased hardening with increasing strain rate.

Dislocation Motion in High Strain-Rate Deformation. Z.Q.Wang, I.J.Beyerlein, R.Lesar: Philosophical Magazine, 2007, 87[16], 2263-79