A study of grain orientation of Alkali doped polycrystalline YBCO ceramics using an EBSD technique

Abstract

Polycrystalline KClO₃-, K₂CO₃-, Rb₂CO₃-doped and undoped YBa₂Cu₃O_7−x (YBCO) ceramic high-T_c superconductors were examined using electron backscatter diffraction (EBSD) technique. We present orientation maps and pole figures of the samples. It is shown that the pure YBCO samples and the ones with Rb₂CO₃ and K₂CO₃ additives do not exhibit a very pronounced texture (i.e. preferred orientation). On the polycrystalline KClO₃-doped YBCO samples we find two major grain orientations (0 0 1) and (1 0 0) normal to the sample surface while the pure YBCO sample does not exhibit any orientation maxima. This observation is ascribed to the effect of a liquid phase due to the KClO₃-additive during the preparation process.