On the measurement of dislocation damping forces at high dislocation velocity

Abstract

In direct mobility experiments in single crystals, dislocation velocity is studied as a function of stress by the application of short-duration stress pulses. The stress pulse consists of a loading wave, followed microseconds later, by an unloading wave. At high velocities, dislocation inertia effects become important if the dislocation damping force is a decreasing function of dislocation velocity. In general, the magnitude of this force can be determined only if the relative velocity between the applied stress wave and the dislocation is considered.