Abstract

Corundum-spinel castables have been widely used as working lining in ladle due to their excellent properties and easy installation. With increased demand for saving high-quality resources and energy, more attention has been devoted to the researches on the lightweight refractories for working linings of industrial furnaces. In order to fabricate the lightweight corundum-spinel castables, the bulk density of dense aggregate must be decreased. The decreasing bulk density of aggregate may affect the strengths and slag resistance of castables, which determines whether the lightweight castables could be used as working lining of ladle or not.

In the early work, the porous corundum-spinel ceramics have been prepared through an in-situ decomposition pore-forming technique, which is an excellent lightweight aggregate for fabricating lightweight refractories. In order to improve the slag resistance of lightweight corundum-spinel castables, additives are needed to adjust the microstructure and composition of the matrix. SiC has lower wettability by molten slag, and can increase the SiO2 content of the penetrated slag after reaction with slag to increase the viscosity of slag, and thus inhibits the penetration of the slag. But until now, when the porous corundum-spinel ceramics are used as aggregates to prepare lightweight corundum-spinel castables, the effect of the SiC content on the slag resistance still has not been understood. This will be addressed in the present work.