At the very beginning of the deformation of a crystal, surface sources are activated before internal sources of same length. X-ray topographs of slightly deformed f.c.c. metal crystals exhibit particular configurations of dislocations induced by the presence of the external boundary. The experimental facts can be explained by a simple model of surface source and its different mechanisms of expansion under an applied stress.

F. Minari

Papers

Dislocations and free surfaces in the microplastic deformation of f.c.c. metals: an x-ray topographic study