We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Multigrain indexing of unknown multiphase materials.
- Authors
Wejdemann, Christian; Poulsen, Henning Friis
- Abstract
A multigrain indexing algorithm for use with samples comprising an arbitrary number of known or unknown phases is presented. No a priori crystallographic knowledge is required. The algorithm applies to data acquired with a monochromatic beam and a conventional two-dimensional detector for diffraction. Initially, candidate grains are found by searching for crystallographic planes, using a Dirac comb convoluted with a box function as a filter. Next, candidate grains are validated and the unit cell is optimized. The algorithm is validated by simulations. Simulations of 500 cementite grains and ∼100 reflections per grain resulted in 99.2% of all grains being indexed correctly and 99.5% of the reflections becoming associated with the right grain. Simulations with 200 grains associated with four mineral phases and 50-700 reflections per grain resulted in 99.9% of all grains being indexed correctly and 99.9% of the reflections becoming associated with the right grain. The main limitation is in terms of overlap of diffraction spots and computing time. Potential areas of use include three-dimensional grain mapping, structural solution and refinement studies of complex samples, and studies of dilute phases.
- Subjects
MULTIPHASE flow; FLUID flow; CRYSTALLOGRAPHY; MONOCHROMATIC light; MONOCHROMATIC aberration
- Publication
Journal of Applied Crystallography, 2016, Vol 49, Issue 2, p616
- ISSN
0021-8898
- Publication type
Article
- DOI
10.1107/S1600576716003691