Investigation of High‐Alumina Spinel: Effect of LiF and CaCO3 Addition

This work examines the effects of LiF or LiF/CaCO 3 additives on the phases, microstructure, sintering temperature, and activation energy of MgO-Al 2 O 3 spinel formation. According to these results, the spinel formation temperature decreases and the spinel phase content increases by incorporating sintering additives. Such an effect is due to the formation of liquid phases at sintering temperatures. The Al composition in spinel is substantially higher in samples containing LiF or LiF/CaCO 3 than in samples without sintering additives. Results obtained from the Arrhenius equation and Jander's model indicate that the activation energy for forming spinel decreases by incorporating LiF or LiF/CaCO 3 .