Small-angle scattering studies of inhomogeneities in condensed matter

The experimental methods of small-angle scattering of X-rays, neutrons and light have been established as excellent tools for investigating particulate inhomogeneities in condensed matter media in the size range of 10 Å-10000 Å. In this paper we bring out the usefulness of small-angle X-ray scattering studies of particulate microstructure in condensed matter. Notwithstanding the extreme extensivity of the field of its applicability, we shall discuss in detail only one field, namely, precipitation of second phase particles in phase separating alloys. Specifically, we shall analyse the example ofγ’ precipitation in Ni0·8Al0·2 alloy system in order to demonstrate the efficacy of the small-angle scattering techniques. We shall touch upon the maximum entropy technique, a relatively new and efficient method of SAXS data analysis, used to derive material data with excellent certainty and statistics from these experiments.