Distribution of dislocations in glide bands of KCl single crystals

Abstract

Local dislocation densities were measured in glide bands of deformed KCl single crystals revealed by etching. The distributions of local dislocation densities are obtained and their variations along the glide bands, and from one band to another are studied. The degree of agreement of the experimental histograms with two standard distribution functions (Poisson and Gauss), corresponding to random and correlated distributions, respectively, shows that the distribution of screw dislocations agrees with the Poisson-like shape along the total band length. Edge bands show various distribution forms: “Poissonian” as well as “Gaussian” regions are observed. The “Gaussian” behaviour of the distribution in edge bands is related to the elastic interaction between dislocations. The correlation found between the form of the distribution function and the dislocation density is explained on the basis of increasing contribution of this interaction with increasing dislocation density. It is shown that separate portions of the glide band cannot be regarded as representative for the entire glide band, because the parameters of the distribution function and its form change along the glide band. [Russian Text Ignored].