| Abstract Scope |
Dislocation mobility laws are essential to crystal plasticity modeling. For dislocations following the kink-pair mechanism, however, existing formulations are often restricted to specific regimes due to the complex interplay between stochastic kink-pair nucleation and lateral kink migration. We formulate the average dislocation velocity resulting from the kink-pair mechanism as a function of: kink-pair nucleation rate, kink migration velocity, dislocation segment length, critical kink-pair width, and kink height. Through probabilistic cellular automaton simulations, the propagation of conceptual dislocation segments is tracked across a wide range of conditions, and their average velocities are fit using a hyperbolic tangent function. The resulting full-range formulation remains valid for arbitrary combinations of the five variables, and is therefore compatible with a wide variety of underlying kinetic laws. Comparisons with established models demonstrate the consistency and robustness of the new formulation, making it suitable for diverse material systems in which the kink-pair mechanism governs dislocation motion. |