Electron backscatter diffraction

Electron backscatter diffraction (EBSD) maps crystal orientations and related microstructural features by analyzing diffraction patterns produced when a scanning electron microscope beam interacts with a crystalline specimen.

Kikuchi bands: Paired lines or bands in electron diffraction patterns formed by diffraction from families of crystal planes. Their geometry in an EBSD pattern encodes the specimen crystal’s orientation.
Grain boundary: The interface separating crystals with different crystallographic orientations in a polycrystalline material. Orientation maps reveal grain boundaries and their misorientation angles.
Crystallography: The study of crystal structures, symmetry, and the geometric arrangement of atoms in solids. EBSD interprets diffraction using the symmetry and lattice geometry of crystals.
Electron backscatter diffraction versus transmission Kikuchi diffraction: A transmission electron diffraction technique in an SEM that records Kikuchi patterns from thin specimens. TKD uses transmission through a thin sample and can resolve finer structures than conventional EBSD.
William R. W. Wilson: A British physicist whose work included early studies of electron diffraction patterns from bulk crystalline materials. His observations helped establish the experimental basis for backscatter Kikuchi patterns.
Bragg diffraction: The constructive interference of waves scattered by regularly spaced planes when the Bragg condition is met. Diffraction from crystal planes produces the bands used to determine orientation.
Texture (crystallography): The statistical distribution of crystallographic orientations in a polycrystalline material. Orientation measurements across many grains establish crystallographic texture.
Scanning electron microscope: An instrument that scans a focused electron beam across a specimen and detects emitted or scattered signals. EBSD is performed inside an SEM using its beam and specimen chamber.
Electron backscatter diffraction versus electron backscatter diffraction simulation: A theory that models electron diffraction by solving for multiple scattering within a crystal. Dynamical simulations predict detailed patterns, while routine EBSD indexing often uses simpler geometric models.
Geoffrey H. J. W. Bunge: A German crystallographer known for developing quantitative methods for crystallographic texture analysis. Texture analysis provided mathematical tools later used to interpret orientation maps.

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