Abstract:The Al2O3- SiC- C iron trough ramming mix was prepared using extra grade bauxite (particle size:8- 5 , 5- 3 and 3- 1mm), brown corundum (particle size:3- 1、≤1 and ≤0.074mm), silicon carbide (particle size:≤1 and ≤0.074mm) and ball pitch as main starting materials, metallic silicon and boron carbide as antioxidant and sintering aid, adding ultra- micro powders or Jiaozuo clay, colloidal silica as binder, ramming and shaping. Effect of silica micropowder, α- Al2O3 micropowder, Jiaozuo clay and organic explosion- proof fiber on properties of colloidal silica bonded Al2O3- SiC- C iron trough ramming mix were studied. The results show that: 2% quality score silica micropowder, 3% quality score Jiaozuo clay or 0.05% quality score organic explosion- proof fiber has little influence on bulk density of colloidal silica bonded Al2O3- SiC- C iron trough ramming mix; specimen with 9% quality score α- Al2O3 micropowder, and the specimen with 6% quality score α- Al2O3 micropowder and 3% quality score Jiaozuo clay exhibit better cold strength. Rational particle size distribution could improve the slag resistance of iron trough ramming mix specimen; specimen with 6% quality score α- Al2O3 micropowder and 3% quality score Jiaozuo clay has the best slag resistance; specimen with 7% quality score α- Al2O3 micropowder and 2% quality score silica micropowder has the second place; and the specimen with 9% quality score α- Al2O3 micropowder has the worst slag resistance. Organic explosion- proof fiber can improve the dried strength of ramming mix, but reduce slag resistance. The specimens of colloidal silica bonded Al2O3 - SiC- C iron trough ramming mix have mass increase after fired at 1450℃, which can improve volume stability and slag resistance.