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Updated: Jan 23, 2026
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Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction
Published on: April 1, 2017
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On the depth resolution of transmission Kikuchi diffraction (TKD) analysis
Junliang Liu1, Sergio Lozano-Perez1, Angus J Wilkinson1
1Department of Materials, University of Oxford, Parks Road, OX1 3PH, United Kingdom.
Ultramicroscopy
|June 25, 2019
Summary
Transmission Kikuchi diffraction (TKD) depth resolution is limited by thermal diffuse scattering (TDS). Optimal sample thickness for TKD analysis depends on material crystal symmetry and scattering properties.
Area of Science:
- Materials Science
- Crystallography
- Electron Microscopy
Background:
- Transmission Kikuchi diffraction (TKD) is a powerful technique for analyzing crystal structures at the nanoscale.
- Understanding the depth resolution of TKD is crucial for accurate microstructural characterization.
- Surface sensitivity in TKD can lead to asymmetric observations of grain structures.
Purpose of the Study:
- To analyze the depth resolution of on-axis transmission Kikuchi diffraction (TKD).
- To determine the origin of signals contributing to Kikuchi band formation.
- To provide guidelines for optimal sample thickness in TKD analysis.
Main Methods:
- Utilized on-axis transmission Kikuchi diffraction (TKD).
- Employed a Zr-Nb alloy for experimental analysis.
- Investigated signal origins related to thermal diffuse scattering (TDS).
Main Results:
- TKD signals originate from a depth approximately equal to the mean free path of thermal diffuse scattering (λTDS) from the sample's bottom surface.
- Surface sensitivity of TKD can result in observing different grain structures from opposite foil surfaces.
- Identified optimal sample thickness guidelines: ≤ 6λTDS (21λMFP) for high symmetry, and ≤ 3λTDS (10λMFP) for low symmetry materials.
Conclusions:
- The depth resolution in TKD is primarily governed by the mean free path of thermal diffuse scattering.
- Sample thickness is a critical parameter influencing TKD results, especially for nano-crystalline foils.
- The findings offer practical guidance for optimizing sample preparation and experimental parameters in TKD studies.
Keywords:
Depth resolutionNanocrystalline materialThermal diffuse scatteringTransmission Kikuchi diffraction (TKD)Zr alloysMore Related Videos
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