QUANTUM-MECHANICAL ASPECTS OF DISLOCATION-MOTION AND PLASTIC-FLOW

The movement of dislocations in response to a finite-amplitude shear stress is treated as a quantum-mechanical process in which the dislocations tunnel through the lattice potential barriers and transit into adjacent potential wells. For simple potential barriers, the predicted dislocation velocity and macroscopic plastic strain rate contain all of the essential features observed in shock and impact experiments. Insights are provided into electroplastic effects and into a possible microscopic mechanism of crystal failure.