Small-angle X-ray scattering from internal stress sources which were described by an incompatibility field in isotropic and cubic crystals was studied, for arbitrary crystal symmetry, within the framework of linear anisotropic elasticity theory. By exploiting an unique decomposition of the elastic strain tensor into deformational and incompatible parts, as an ansatz, the small-angle X-ray scattering amplitude was obtained via Fourier transformation of the basic equations of internal stress theory. The integration problem could be reduced to Fourier transformation of the incompatibility tensor alone. In this way, calculations of the volume dilatation field could be avoided. The calculated small-angle X-ray scattering amplitude was applied to dislocation loops in hexagonal close-packed crystals. It was determined which information concerning dislocation loops could be deduced by measuring small-angle X-ray scattering intensity contours.

Theory of Small-Angle X-Ray Scattering Caused by Incompatibilities in Elastic Anisotropic Media and Application to Dislocations in Hexagonal Close-Packed Crystals. T.Michelitsch: Physica Status Solidi B, 1997, 203[1], 3-16