The combined effects of lattice friction and localized obstacles upon dislocation velocity were considered. The 2 effects were first considered separately. The velocity of an individual dislocation was described by the Hirth-Lothe equation for the case of lattice friction, and by a power law for the case of localized obstacles. The power law was modified so as to introduce a static waiting time (during which the dislocation had to wait in its equilibrium configuration at an obstacle until it broke away under thermal activation). A combination of the 2 mechanisms was then described. A dynamic waiting time was introduced which corresponded to the situation in which a dislocation overcame the obstacle before it reached the equilibrium configuration. The model provided a good description of the effects when they were independent, and also interpolated the 2 regimes.

Dislocation Motion in Crystals with a High Peierls Relief - a Unified Model Incorporating the Lattice Friction and Localized Obstacles. G.Dour, Y.Estrin: Journal of Engineering Materials and Technology, 2002, 124[1], 7-12