X-ray diffraction analysis of an ε/γ' iron-nitride compound double layer

An -Fe3N/ -Fe4N double compound layer grown on -Fe was investigated by Xray diffraction analysis. The anisotropic diffraction-line broadening observed by highresolution synchrotron diffraction measurements and the diffraction-line shifts as measured for hexagonal layer can be quantitatively explained by the presence of both a lattice parameter gradient associated with a concentration gradient and a stress gradient within the layer. Investigation of the layer revealed an elastic anisotropy unusual for fcc type metals.