Open AccessAssessment of deviatoric lattice strain uncertainty for polychromatic X‐ray microdiffraction experiments
Author(s) -
Poshadel Andrew,
Dawson Paul,
Johnson George
Publication year - 2012
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049511050400
Subject(s) - monte carlo method , spurious relationship , lattice (music) , statistical physics , computational physics , infinitesimal strain theory , materials science , optics , physics , mathematics , acoustics , thermodynamics , finite element method , statistics
X‐ray microdiffraction is a powerful technique for conducting high‐spatial‐resolution lattice strain measurements. However, there has been limited validation of the technique to date. An experiment was conducted at the Advanced Light Source to assess the uncertainty of deviatoric lattice strains measured using polychromatic X‐ray microdiffraction. It is shown that the measurement uncertainty is different for each component of the deviatoric lattice strain tensor. Monte Carlo simulations of the experiment are used to explain the differences in uncertainty. The simulations point to the existence of spurious deformation modes that arise erroneously in the strain calculation owing to measurement noise and limited pole figure coverage. Methods for reducing measurement uncertainty are proposed.