| 摘要 |
PROBLEM TO BE SOLVED: To provide a ramming material used for an induction furnace as a material for lining the inner surface of the induction furnace, having excellent corrosion resistance and thermal shock resistance and not causing the advance of a crack to the coil side of a non-operated surface, even when the crack is generated on an operation surface due to the flow friction of a molten metal and thermal shock, because the ramming material forms a compact sintered layer on the operation surface in a proper thickness and leaves a powder layer without being hardened up to the coil side of the non-operated surface, and thereby capable of avoiding the generation of troubles such as the leak of the molten metal. SOLUTION: This ramming material for introduction furnaces comprises 1-7 wt.% of a powdery material having a particle diameter of >=0.5 mm, 30-80 wt.% of molten silica having a SiO2 purity of >=98% and a granule diameter of <=5 mm and the remainder of natural silica having a SiO2 purity of >=98% and a granule diameter of <=5 mm. The powdery particles having the particle diameter of <=0.5 mm are obtained by grinding a sintered product or a molten and solidified product having a porosity of <=2% and comprising 67-77 wt.% of SiO2 component, 18-28 wt.% of Al2 O3 component and totally 2-7 wt.% of at least one kind of component selected from TiO2 , Fe2 O3 , CaO, MgO, Na2 O and K2 O. |
