diffraktography

Diffraktography, also spelled diffractography, is the study and interpretation of diffraction patterns produced when waves such as X-rays, electrons, or neutrons interact with a crystalline material. By analyzing the angular distribution and intensity of diffracted radiation, scientists infer information about crystal structure, phase composition, lattice parameters, strain, and microstructure.

Common implementations include X-ray diffractography (XRD), which probes bulk materials and powders to identify phases and measure lattice spacings; transmission electron diffraction for local crystallography within a thin specimen; and electron backscatter diffraction (EBSD) in scanning electron microscopy for mapping crystal orientation and texture. Neutron diffractography is used for complementary information, particularly in light elements or deep within bulk materials.

Applications span phase identification and quantitative phase analysis, determination of lattice parameters and crystal symmetry, detection of residual stresses and microstrain, estimation of crystallite size and defect content from peak broadening, and texture or grain-orientation mapping. Advanced analyses employ Rietveld refinement, whole-pattern fitting, and micro-diffraction techniques to extract detailed structural information from diffraction data.

Data interpretation centers on Bragg’s law, with peak positions revealing d-spacings and lattice geometry, and peak intensities relating to structure factors and phase fractions. Limitations include peak overlap, instrumental broadening, sample preparation effects, and potential preferred orientation or radiation damage in electron-based methods. See also X-ray diffraction, electron diffraction, EBSD, and Rietveld refinement.