Studies of polycrystalline materials by Pseudo Kossel technique

In contrast to the Kossel Technique the Pseudo Kossel Technique (PKT) is ma inly used for investigations of single crystals to determine the crystal st ructure, the crystallographic orientation and lattice parameter of the spec imens so far. Though the PKT has yet large possibilities and is well-suited also for micro range investigations, the application for the characterizat ion of polycrystalline materials is not common. The complicated con-figurat ion of the reflex sections in polycrystals, caused by grain boundary effect s, usually makes it very difficult to evaluate them. The studies have been carried out at Al and BaTiO3 polycrystals. Thus, for the first time the suc cessful application of the technique to a ceramic was demonstrated. The dep endence of the reflex length on the grain size was investigated by simulati on. It is shown that this technique allows precise determination of correla tion between neighbor grains, since one diffraction pattern contains contri butions from several grains. As a result one obtains for example the relati ve orientations of neighbor grains, which influence among other things the electrical and mechanical properties.