Aqueous Slip Casting Research Articles

Influence of Additions on the Fusion of Magnesia and Sintering Behaviour

Magnesia is a highly refractory oxide and finds use in many applications above 1800°C. Sinterable magnesia powders can be made by calcination of parent compounds but due to hydration, these are not amenable for aqueous medium slip casting or tamping, for which fused magnesia powders are more suitable. However, arc-fusion of magnesia is difficult and costly. Therefore, the addition of Al2O3, ZrO2 and TiO2 to magnesia was investigated for fusion and the sintering behaviour of the fused material was studied. The addition of the oxides facilitated the fusion of magnesia at moderate powder inputs. The material thus obtained could be slip cast and sintered to 85–96% theoretical density at sintering temperatures between 1400° and 1500°C.