Small-angle scattering studies of phase separation and defects in inorganic materials

The use of X-ray and neutron small-angle scattering in the study of microstructural changes in inorganic materials is reviewed, with emphasis on recent developments. In the kinetics of diffusion-controlled phase separation, reliable data on the evolution of size and shape of the decomposition products may be obtained especially from in situ ageing experiments. Magnetic neutron scattering is discussed for inhomogeneous ferromagnets. While for the structural characterization of binary systems single-wavelength experiments are sufficient, variable X-ray wavelengths now available at synchrotron-radiation facilities open possibilities for the study of partial structure functions in systems containing several components. The combined use of small-angle scattering and complementary techniques is of particular value in more complex cases. These points are illustrated by a survey of recent results on phase separation and precipitates in binary and ternary crystalline alloys and on radiation-induced microstructural changes in metallic and semiconducting materials.