EXACT ANALYSIS OF AN EDGE DISLOCATION NEAR A SURFACE LAYER

Some explanations of how very thin coatings affect mechanical properties of crystals are based on the interaction of the surface layer with dislocations. Although analysis of this interaction has been accomplished for a screw dislocation, the equally interesting case of an edge dislocation has not been solved up to this time. The present paper provides an exact analysis of an edge dislocation near a surface layer with no restrictions other than isotropy. The results show that the edge dislocation has stable equilibrium positions whenever it is repelled by the layer nearby. Especially for layers with higher shear moduli, the equilibrium positions are much closer to the layer than for screws dislocations. © 1968.