Electron Backscattering Diffraction · Electron backscatter diffraction (EBSD) is a Scanning...

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Electron Backscattering Diffraction

2019/06/14

Yifan Yuan

The inelastically scattered electrons can subsequently be elastically scattered that is Bragg diffracted by lattice

planes to produce a phenomenon known as Kikuchi lines

Electron backscatter diffraction (EBSD) is a Scanning Electron Microscope based microstructural-crystallographiccharacterization technique commonly used in the study of crystalline or polycrystalline materials.

Kossel cones:

The stereographic projection transforms great circles on the sphere into circles.Conversely, the gnomonic projection transforms all great circles into straight lines.

Projections onto a plane

How to draw Kikuchi lines for FCC lattice?

(020) planes

Electron beam [001] pole

020 Kikuchi line

𝒈020

0ത20 Kikuchi line

Step 1: construct [001] Kikuchi pattern

DF with [001] pole

Step 2: construct [101] patternPole figure

Knowing the [001] pattern we can construct the [101] pattern since a pair of lines is common to both

DF with [101] pole

Reciprocal spaceReal space Real space

ത1ത1111ത1

Step 3: construct [112] pattern Pole figure

Step 3: construct [111] and [011] pattern

Experimental Kikuchi map for fcc crystals and (B) indexed Kikuchi lines in the schematic map

Au(FCC) Kikuchi map Kikuchi map of croconic acid (orthorhombic)

References

David B. Williams, C. Barry Carter. Transmission Electron Microscopy A Textbook for Materials Science. Springer. 2009