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Title: Extending 4D-STEM to Defect and Short-range Ordering Analysis: Principles, Methodology and Applications
This talk focuses on the principles of 4D-STEM based electron nanodiffraction techniques for defect, strain and short-range ordering analysis using electron diffuse scattering [8, 9]. We review recent progress made in scanning electron nanodiffraction (SEND) data collection, new algorithms based on cepstral analysis, and machine learning based electron DP analysis. These progresses will be highlighted using defect detection, and short-range ordering analysis as application examples. The materials of the study are the medium entropy alloy, CrCoNi, which has exceptional low-temperature mechanical strength and ductility. We will show how SEND helps our understanding of non-random chemical mixing in a CrCoNi alloy, resulting from short-range ordering, behind the mechanical strength in CrCoNi and how these developments provide general opportunities for an atomistic-structure study in advanced alloys.  more » « less
Award ID(s):
2226495
PAR ID:
10466758
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Microscopy and Microanalysis
Volume:
29
Issue:
Supplement_1
ISSN:
1431-9276
Page Range / eLocation ID:
249 to 250
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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