Scanning transmission electron microscopy image simulations of complex dislocation structures generated by discrete dislocation dynamics

Joseph Tessmer; Saransh Singh; Yejun Gu; Jaafar A El-Awady; Marc De Graef

doi:10.1016/j.ultramic.2020.113124

Scanning transmission electron microscopy image simulations of complex dislocation structures generated by discrete dislocation dynamics

Ultramicroscopy. 2020 Dec:219:113124. doi: 10.1016/j.ultramic.2020.113124. Epub 2020 Sep 24.

Authors

Joseph Tessmer¹, Saransh Singh², Yejun Gu³, Jaafar A El-Awady³, Marc De Graef¹

Affiliations

¹ Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
² Lawrence Livermore National Lab, Computational Engineering Division, Livermore, CA 94550, USA.
³ Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA.

PMID: 33032162
DOI: 10.1016/j.ultramic.2020.113124

Abstract

Scanning Transmission Electron Microscopy Diffraction Contrast Imaging (STEM-DCI) has been gaining popularity for the identification and analysis of dislocations in crystalline materials due to its ability to supress undesirable image features that are often present in conventional TEM images. However, there does not yet exist a robust body of work demonstrating expected contrast in these imaging conditions. A novel approach for the simulation of STEM-DCI images was developed using a modified form of the scattering matrix formalism. This algorithm was used to simulate a variety of dislocation configurations generated using three-dimensional discrete dislocation dynamics.

Keywords: Diffraction; Discrete Dislocation Dynamics; STEM-DCI; Scanning Transmission Electron Microscopy - Diffraction Contrast Imaging; Simulation.