KINEMATIC GENERATION OF DISLOCATIONS

In this letter we present evidence from computer simulations that edge dislocations can be generated by purely kinematic processes, in the absence of more conventional dislocation sources. New dislocation pairs may be generated near high-velocity dislocations. These kinematic processes are only active under high stresses but may be important under shock loading or under other conditions where a very high strain rate is obtained. This dislocation generation becomes possible because the sign of the force between edge dislocations changes when the dislocation velocity exceeds the Rayleigh velocity.