Through-thickness texture profiling by energy dispersive synchrotron diffraction

Abstract

Two new approaches that make use of the advantages of energy dispersive diffraction were applied to investigate through-thickness variations of the crystallographic texture: the `real-space' and the `Laplace-space' methods. The first consists of defining a small gauge volume by adding a pair of slits in the primary and the diffracted beams. Thus the depth resolution is achieved by a decoupledztranslation of the gauge through the sample. The second method is based on the Beer attenuation law, and the depth resolution is achieved by assigning pole figures of different order reflections (e.g.0002, 0004…) to different average information depths. Wrought rolled AZ31 magnesium alloy was selected as a `model' material for the experiments because of the low X-ray absorption of Mg. The through-thickness crystallographic texture variation was generated by sample bending. The results give a first insight into the possibilities of fast texture depth profile investigation applying nondestructive methods and represent a step forward towards a simultaneous evaluation of residual stress and texture gradients.