Orientational Effect of the Dynamical Interaction of Circular Dislocation Loops with a Moving Edge Dislocation

摘要

The glide of an edge dislocation in a crystal containing circular dislocation loops is studied theoretically. An analytical expression is obtained for the drag force exerted on a dislocation by various types of dislocation loops, and it is shown that this force depends significantly on the orientation of the Burgers vector of immobile dislocation loops with respect to the gliding dislocation line. The F-parallel to/F-perpendicular to ratio of the drag force for the parallel orientation of the Burgers vectors of the loops with respect to the gliding dislocation line (F-parallel to) and the drag force for the perpendicular orientation (F-perpendicular to) is equal to K(v/c)(2), where v is the velocity of the dislocation; c is the velocity of acoustic waves in the crystal; and K is a dimensionless coefficient, whose value is of the order of the ratio of the concentrations of dislocation loops with parallel and perpendicular orientations of the Burgers vector.