Effect of Cr ₂ O ₃ on Slag Resistance of Al ₂ O ₃ –SiO ₂ Refractories

Abstract

Refractory bodies of 65 wt% Al 2 O 3 were prepared from a mixture of calcined alumina and raw kaolin with the addition of Cr 2 O 3 up to 15 wt%. The Cr 2 O 3 addition effectively enhances slag resistance and reduces mullite formation. Petrographic analysis of the refractories after the slag test suggests that Cr 2 O 3 increases the viscosity of both the glassy phase in the refractory as well as the slag, thereby retarding slag penetration and reaction at elevated temperature.