University of Technology of Troyes 1 article published in JoVE Engineering Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction Gwénaëlle Proust1, Patrick Trimby2, Sandra Piazolo3, Delphine Retraint4 1School of Civil Engineering, The University of Sydney, 2Australian Centre for Microscopy and Microanalysis, The University of Sydney, 3Department of Earth and Planetary Sciences, Macquarie University, 4Charles Delaunay Institute, LASMIS, UMR STMR CNRS 6281, University of Technology of Troyes This paper provides a detailed method to characterize the microstructure of ultra-fine grained and nanocrystalline materials using a scanning electron microscope equipped with a standard electron backscatter diffraction system. Metal alloys and minerals presenting refined microstructures are analyzed using this technique, showing the diversity of its possible applications.