Sintering of K-beta-aluminas in the system K2O-Al2O3-Li2O was carried out at atmospheric pressure. The influence of Li2O as a stabilizer on densification and ionic conductivity, depending on its content, has been investigated. In order to lower the sintering temperature, the calcined powders were ultra-fine milled by an attrition mill. Relations between sintering density, microstructure and ionic conductivity were studied. The samples were prepared in the molar ratio range [K2O]:[Al2O3]=1:5-1:11, and the Li2O content was varied from 0 to 1.6 wt%. The maximum ionic conductivity has been observed with the sample having a molar ratio of [K2O]:[Al2O3]=1:5 and containing 0.8 wt% of stabilizer. This sample showed 97% density and its ionic conductivity was measured to be 1.1x10(-1) and 5x10(-3) S/cm at 800 degrees C and 300 degrees C, respectively.

Keywords: K-beta-aluminas; sintering; ionic conductivity; stabilizer (Li2O)