The theory of small angle scattering from dislocations

Abstract

Abstract The small angle scattering of x-rays or neutrons from crystals containing a random network of dislocations is calculated. Three causes of density changes associated with dislocations are considered : that due to the elastic strain field from edge dislocations, that due to second-order elasticity effects and that due to the dislocation cores. It is found that in the range of angles for which experimental evidence is available, the effect due to the elastic strain field from edge dislocations predominates. The magnitude of the scattering expected from the theory for a dislocation density of about 1011 cm−2 is of the same order as that found recently from small angle neutron scattering experiments on heavily cold-worked copper.