Analytic model of the remobilization of pinned glide dislocations from quasi-static to high strain rates

•A kinetic equation describing mobile-immobile dislocation interactions is derived.•Relates plastic strain rate to applied stress, dislocation densities, and temperature.•Kinetic equation applies to high strain rate, pressure, and temperature regimes.•Kinetic equation does not rely on standard activation theory.•Mean-first-passage-time theory specific to dislocation intersections is developed.

In this paper, we construct an analytic model describing mobile-immobile dislocation intersections using a mean-first-passage-time (MFPT) framework. By applying MFPT theory to dislocation intersection, the deformation mechanics at high strain rates is more reliably described than in traditional models based on Van't Hoff-Arrhenius thermal activation. The plastic strain rate is expressed as a function of the applied stress, mobile and immobile dislocation densities, material density, and temperature. This kinetic equation is applicable at strain rates from quasi-static to rates in excess of 1012 s−1, pressures from ambient to about 1000 GPa, and temperatures ranging from zero to the melt temperature.