Force on a screw dislocation in a multiphase laminated structure

Abstract

The force on a screw dislocation in a multiphase laminated elastic structure is determined, both as an infinite integral and as a sum of multiple image terms. When the dislocation is near an interface, it is found that dislocation mobility is largely dependent on the ratio of the rigidities of the adjacent materials, and the perpendicular distance of the dislocation from the interface becomes the important length scale. When the dislocation is far from the interface layers, it is found that a combination of an odd number of alternate strata of two different materials has a stabilizing influence on the dislocation. Further, if two dissimilar semi-infinite planes are separated by any number of dissimilar thick layers, then the force on a screw dislocation at large distances is independent of the physical properties of the interface layers.