|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||Characterization of Minerals, Metals and Materials
||On the Depth Resolution of Transmission Kikuchi Diffraction (TKD) Analysis
||Junliang Liu, Sergio Lozano-Perez, Angus J. Wilkinson, Chris R.M. Grovenor
|On-Site Speaker (Planned)
Transmission Kikuchi diffraction (TKD) has been widely utilized in the characterization of nano-crystalline materials, but a better understanding of the achievable depth resolution is still required to understand the potential and the limitations of this technique. In this work we report on experimental measurements on model Zr-Nb alloys of the depth resolution achievable using an on-axis TKD system. The results indicate that the signals contributing to Kikuchi bands originate from a depth of approximately the mean free path of thermal diffuse scattering from the bottom surface of samples, ~20 nm in Zr-Nb alloy. This strong surface sensitivity can thus lead to the observation of different grain structures when opposite sides of the same region of a nano-crystalline foil are scanned. These results also provide a guideline for the optimum sample thickness in order to achieve clear and indexable Kikuchi patterns for TKD analysis.