Dislocation induced line-broadening in cold-worked Pb-Bi binary alloy system in the α-phase using X-ray powder profile analysis

Abstract

An X-ray diffraction line profile analysis on cold-worked Pb-Bi alloys in the α- phase is presented. The anisotropic broadening of X-ray diffraction lines has been interpreted in terms of dislocation induced strain broadening only. Dislocations are found to be predominantly of screw type from a modified Williamson–Hall analysis. Due to the almost symmetric shape of the X-ray line profiles, a restrictedly random dislocation distribution was assumed in the modified Warren–Averbach analysis. The dislocation densities are of the order of 10 11 cm −2 and decrease for annealed specimen. The dislocation arrangement parameter ( μ) decreases from more than 1.0 for cold-worked samples to less than 1.0 for annealed samples. This indicates a rather short ranged strain fields in annealed samples compared to cold-worked samples. Relative change in the dislocation arrangement parameter increases with solute concentration.