To investigate the effects of lattice periodicity on kink motion, a molecular-dynamic simulation for a kink in a screw dislocation was performed in a simple model lattice of diamond type. The Stillinger–Weber potential was assumed to act between atoms. Under applied stresses larger than 0.0027G, a long distance motion of a kink was possible, where G was the shear modulus. A moving kink emits lattice waves and loses its kinetic energy, which was compensated by the applied stress. The kink attains a terminal velocity after moving a few atomic distances. The kink velocity was not proportional to the applied stress, and exceeds the shear wave velocity when the applied stress was larger than 0.026G. The energy loss of the moving kink was one order of magnitude smaller than that of a moving straight dislocation and was about the same order of magnitude as the theoretical value of phonon-scattering mechanisms at room temperature.

Motion of Dislocation Kinks in a Simple Model Crystal. H.Koizumi, T.Suzuki: Materials Science and Engineering A, 2005, 400-401, 76-9