Residual stress analysis using overlapping diffraction peaks. Case of textured cubic materials

Abstract

Residual stresses in polycrystalline materials can be determined from the 20 shift of a reflection peak's line profile. Recently, multiple reflections have been used for residual stress analysis in single-phase textured cubic materials. Analogously, residual stresses in twophase materials could be determined from overlapping peaks of both phases. Equations are derived for residual stress analysis using partially or completely overlapping diffraction peaks. Mainly textured cubic materials are considered. It is shown that the so-called quasi-isotropic diffraction elastic constants become connected to texture-dependent quantities. In the examples treated the calculated diffraction strains of three multiple reflections exhibit only small nonlinearities although the intensities oscillate strongly.

On the diffractive determination of single-crystal elastic constants using polycrystalline samples

“…It is relatively simple for the texture-free case and for cubic crystal symmetry, and has been applied to the calculation of bulk properties S (Kneer, 1965) as well as to stress analysis (Noyan & Cohen (1987) and the inverse problem (Hauk & Kockelmann, 1979). However, its application in the case of low crystal symmetries and/or textured samples becomes much more complicated, especially if the texture-related operations use the harmonic approach (Morris, 1970;Brakman, 1987).…”