Calculation of the aligned fraction in polycrystalline samples with preferred orientation

Abstract

An analytical expression is derived for the fraction of crystallites which are aligned within an angle, θ (0< θ<90°), of the sample's preferred orientation axis. The expression is given in terms of the preferred orientation parameter obtained in Rietveld refinement of the sample's diffractogram. It is useful in the study of anisotropic materials using aligned polycrystalline samples.