Electron back scatter diffraction and x-ray pole figure analysis of c-axis textured α-alumina fabricated by gel-casting

摘要

In the present research, c-axis textured a-alumina ceramics have been prepared by an alginate-based, gel-cast, doctor-blade process. The macrotexture of the α-alumina ceramics was analysed by x-ray pole figure measurements and the c-axis texture nature was revealed using 00.12, 10.10 and 113 pole figures. In order to examine the regional grain orientation relations (microtexture), electron back scatter diffraction (EBSD) was applied in this work. Using EBSD, the boundary mis-orientation distribution was obtained and analysed. Apart from the well-developed low angle grain boundaries, a large fraction of boundaries were found misoriented in the range of 50-60°, implying the high possibility of forming Σ3 boundary in this c-axis textured α-alumina ceramic. Pole figures and inverse pole figures were also measured by EBSD patterns taken from the grains in the SEM scanned area, which confirms the c-axis texture symmetry determined by x-ray diffraction.