Subgrain Size-Distributions, Dislocation Structures, Stacking- and Twin Faults and Vacancy Concentrations in SPD Materials Determined by X-Ray Line Profile Analysis

Abstract

The fundamentals of X-ray line profile analysis are summarised in terms of subgrain size and size-distribution, dislocation density and dislocation types, especially edge and screw dislocations, intrinsic and extrinsic stacking faults and twin boundaries and vacancies produced during plastic deformation. It is shown that deformation induced vacancy concentrations in the grain boundaries of compressed copper polycrystals are close to the equilibrium values at the melting temperature. The discrepancy between X-ray and TEM size values is discussed in terms subgrain- and grain size. It is shown that this apparent discrepancy might be used to determine the status of fragmentation by severe plastic deformation.