A multireflection and multiwavelength residual stress determination method using energy dispersive diffraction

J Appl Crystallogr. 2018 May 9;51(Pt 3):732-745. doi: 10.1107/S1600576718004193. eCollection 2018 Jun 1.

Abstract

The main focus of the presented work was the investigation of structure and residual stress gradients in the near-surface region of materials studied by X-ray diffraction. The multireflection method was used to measure depth-dependent stress variation in near-surface layers of a Ti sample (grade 2) subjected to different mechanical treatments. First, the multireflection grazing incidence diffraction method was applied on a classical diffractometer with Cu Kα radiation. The applicability of the method was then extended by using a white synchrotron beam during an energy dispersive (ED) diffraction experiment. An advantage of this method was the possibility of using not only more than one reflection but also different wavelengths of radiation. This approach was successfully applied to analysis of data obtained in the ED experiment. There was good agreement between the measurements performed using synchrotron radiation and those with Cu Kα radiation on the classical diffractometer. A great advantage of high-energy synchrotron radiation was the possibility to measure stresses as well as the a0 parameter and c0/a0 ratio for much larger depths in comparison with laboratory X-rays.

Keywords: MGIXD; MMXD; energy dispersive diffraction; hexagonal structures; multireflection and multiwavelength X-ray diffraction; multireflection grazing incidence diffraction; residual stress; synchrotron radiation.

Grants and funding

This work was funded by Narodowym Centrum Nauki grants UMO-2014/15/D/ST8/00542 and UMO-2017/25/B/ST8/00134.