Characterization at high spatial and angular resolutions of deformed nanostructures by on-axis HR-TKD

Global Digital Image Correlation (DIC) is applied on the electron diffraction patterns acquired by the on-axis Transmission Kikuchi Diffraction (TKD) technique. High-angular resolution (HR-TKD) mappings of the grain internal disorientations and the associated geometrically necessary dislocation densities are then derived at a nanoscale resolution. Tailored for the fine characterization of nanomaterials in the scanning electron microscope (SEM), the method is illustrated on a nanostructured high-purity aluminium processed by severe plastic deformation (SPD) and its performances are discussed in the light of imaging by transmission electron microscopy (TEM) and by SEM using a forescatter electron detector (FSD). (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.