The effect of pattern overlap on the accuracy of high resolution electron backscatter diffraction measurements

Vivian Tong, Jun Jiang, Angus J. Wilkinson, T. Ben Britton
2015 Ultramicroscopy  
High resolution, cross-correlation-based, electron backscatter diffraction (EBSD) measures the variation of elastic strains and lattice rotations from a reference state. Regions near grain boundaries are often of interest but overlap of patterns from the two grains could reduce accuracy of the cross-correlation analysis. To explore this concern, patterns from the interior of two grains have been mixed to simulate the interaction volume crossing a grain boundary so that the effect on the
more » ... of the cross correlation results can be tested. It was found that the accuracy of HR-EBSD strain measurements performed in a FEG-SEM on zirconium remains good until the incident beam is less than 18 nm from a grain boundary. A simulated microstructure was used to measure how often pattern overlap occurs at any given EBSD step size, and a simple relation was found linking the probability of overlap with step size.
doi:10.1016/j.ultramic.2015.04.019 pmid:25957534 fatcat:5ytrc2h6sjgwfmmmn7gpxvfvki