Preparation of Forming Powders of High Quality β"-Al2O3 Ceramics

The influences of chemical composition and fabrication technology of forming powders onsintering density, Na-ion conductivity and microstructure of β-Al2O3 ceramics were investigated.Compared with water-based slurry,ethanol-based slurry was more stable and could be preparedmore easily. Moreover, the latter had better stability to moisture and chemical homogeneity,and the agglomerates could be crushed at a lower pressure. Thus, higher green densities couldbe obtained. High quality β-Al2O3 ceramics with densities 3.23g.cm(-3), and resistivities of5-6cm at 300℃ and homogeneous microstructures were prepared with such powder spray driedfrom ethanol-based slurry which was composed of two components, namely Li2O-Al2O3 and Na2OAl2O3 calcinated at 1250℃ for 2h. respectively. The contents of Li2O and Na2O in the resultingpowders were variable in the ranges of 0.69-0.75wt% and 8.85-9.10wt%.