Prediction of potential pseudo-symmetry issues in the indexing of electron backscatter diffraction patterns

Abstract

A new methodology to predict potential pseudo-symmetric or systematically mis-indexed orientations for an arbitrary crystal structure is presented. The method leverages the recently proposed spherical indexing algorithm to index electron backscatter diffraction patterns. Potential pseudo-symmetric orientations are interpreted as secondary peaks in the autocorrelation of the Kikuchi sphere. The generality of the method is illustrated using a number of crystal systems, ranging from nickel, where no significant pseudo-symmetric issues are expected, to SrTiO3, with mild occurrence of such issues, to the olivine series, γ-TiAl and U-6%Nb systems, where the traditional Hough method systematically mis-indexes the pseudo-symmetric variants. Furthermore, the method predicts the severity of potential pseudo-symmetric matches and ranks all variants using a normalized autocorrelation coefficient.

Document Details

Document Type
Pub Defense Publication
Publication Date
Sep 23, 2019
Source ID
10.1107/s1600576719011233

Entities

People

  • Marc De Graef
  • Saransh Singh
  • William Lenthe

Organizations

  • Carnegie Mellon University
  • Office of Naval Research
  • United States Department of Energy

Tags

Readers

  • Approximation Theory.
  • Computational Modeling and Simulation
  • Materials Science and Engineering.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene