Quantitative Evaluation Of Glass-Forming Impurities In Alumina: Equivalent Silica Concentration (Esc)

Equivalent silica concentration (ESC) is proposed as a quantitative measure of the total impurity concentration that contributes to intergranular glass formation in nominally pure alumina. The method involves, in its determination, the processing and sintering of the alumina under contamination-free conditions, as well as measurement of the average grain size at the moment that abnormal grains first appear.