Atomistic study of ⅓〈1123〉{1011} dislocations in h.cp. crystals. II. Motion of the dislocations

Abstract

The effect of shear stress on three ⅓〈1 123〉 dislocations on {1011} planes in h.c.p. crystals has been investigated by computer simulation using a truncated Lennard-Jones potential. An edge dislocation and a 30° mixed dislocation glide on the (1011) plane relatively easily. Three types of 105° dislocations are different in their behaviour under the applied stresses. A dislocation with a planar core (type I) moves at a comparable stress to the above ones, whereas larger stresses are required for the other two; a dislocation with a nonplanar core configuration (type II) begins to move after transformation to a planar, glissile configuration (type I), and a dislocation with another nonplanar configuration (type III) is sessile. The result is discussed and compared with experimental observations.