Tutorial: crystal orientations and EBSD – or which way is up?

Journal article

Electron backscatter diffraction (EBSD) is an automated technique that can measure the orientation of crystals in a sample very rapidly. There are many sophisticated software packages that present measured data. Unfortunately, due to crystal symmetry and differences in the set-up of microscope and EBSD software, there may be accuracy issues when linking the crystal orientation to a particular microstructural feature. In this paper we outline a series of conventions used to describe crystal orientations and coordinate systems. These conventions have been used to successfully demonstrate that a consistent frame of reference is used in the sample, unit cell, pole figure and diffraction pattern frames of reference. We establish a coordinate system rooted in measurement of the diffraction pattern and subsequent linking to all other coordinate systems. A fundamental outcome of this analysis is to note that the beamshift coordinate system needs to be precisely defined for consistent 3D microstructure analysis. This is supported through a series of case studies examining particular features of the microscope settings and/or unambiguous crystallographic features. These case studies can be generated easily in most laboratories and represent an opportunity to demonstrate confidence in use of recorded orientation data. Finally, we include a simple software tool, written in both MATLAB® and Python, which the reader can use to compare consistency with their own microscope set-up and which may act a springboard for further offline analysis.

Authors: Wilkinson, A; Britton, T; Jiang, J; Guo, Y; Vilalta-Clemente, A

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Elsevier
• Journal: Materials Characterization
• Publication date: 2016-01-01
• DOI: 10.1016/j.matchar.2016.04.008
• EISSN: 1873-4189
• ISSN: 1044-5803
• Keywords: electron backscatter diffraction; electron microscopy; crystal orientation; EBSD; texture