X-Ray Subgrain Analysis of Polycrystalline Materials.

Two X-ray techniques are presented, which permit the estimation of grain or subgrain characteristics of polycrystalline materials (e. g. subgrain size and/or disorientation). The first one is the well-known microbeam technique, using traditional film registration of the azimuthal intensity distribution of Debye-Scherrer rings. In the second method, giving possibility of automatization and computerization of data recording and processing, respectively, local statistical fluctuations of the radial intensity distribution are measured by means of a powder diffractometer. Because the intensity fluctuations depend usually on both the grain and the subgrain statistics of the sample, separation of the corresponding effects is necessary. For this purpose a procedure was developed, which is based on the fitting of cubic spline-functions. Experimentally determined subgrain diameters are in good agreement with results of TEM investigations.