RAMMING MATERIAL FOR INDUCTION FURNACE

PURPOSE:To improve corrosion resistance, thermal shock resistance and heat insulation effect and prevent occurrence of crack on operating face and hardening over the rear of executing body by constituting of a specific fused silica and a natural silica without including a sintering binder. CONSTITUTION:Fused silica containing 0.5-3.0wt.% alumina, 0.5-3.0wt.% potassium oxide is included in an amount of 40-80wt.% so as to improve sintering property on a lined operating face and natural silica is substantially added as the residual part excluding impurities thereto. Since boric acid generally used as a sintering binder is not applied, unhardened layer (powder layer) is left on the outer induction coil side. As a result, even if fine crack is produced on the operating face side, penetrated molten ore is surely stopped at this unhardened layer and occurrence of trouble is prevented and resistances to chemical penetration due to molten ore components and physical penetration of molten ore due to electromagnetic agitation are improved, thus the objective ramming material can keep the long-life and durability of induction furnaces.