LADLE HEAT-INSULATING MATERIAL FOR ULTRA-LOW CARBON SPECIAL MOLTEN STEEL, EXCELLENT IN HEAT KEEPING ABILITY, ALUMINA ABSORPTIVITY, AND CORROSION-RESISTANCE TO MAGNESIA REFRACTORY

摘要

PURPOSE: A ladle heat-insulating material for ultra-low carbon special molten steel is provided, which is excellent in a heat keeping ability, an alumina absorptivity of the molten steel slag, and a corrosion-resistance to a magnesia refractory. CONSTITUTION: The ladle heat-insulating material comprises 35-50wt% of MgO, 10-20wt% of CaO, 10-20wt% of SiO2, 5-10wt% of Al2O3, 5-10wt% of a carbon, and the balance of a binder and impurities and has a basicity(CaO/SiO2) of 2.5-3.5. The ladle heat-insulating material is injected into the upper part of the molten steel slag to prevent contact with the outside air, to reduce temperature from lowering, and to reduce change of components.