| 摘要 |
PURPOSE:To prevent abnormal failure by subjecting refractories contg. carbon and alumina as essential components respectively in specific ratios and >=1 kinds among oxide powder, metallic powder, metallic powder and non-oxide powder for refractory raw materials in specific ratios to an impregnation treatment with a 3Ca-2SiO2-ZrO2 alkoxide. CONSTITUTION:The refractories contg. 5 to 30wt.% carbon and 40 to 90wt.% alumina as the essential components and contg. 5 to 30wt.% one or >=2 kinds among the oxide powder, metallic powder, metallic powder and non-oxide powder for the refractory raw materials is subjected to the impregnation treatment with the 3Ca-2SiO2-ZrO2 alkoxide. The 3Ca-2SiO2-ZrO2 alkoxide impregnated in the nozzle for continuous casting contg. the carbon contributes to the improvement in non-adhesiveness of alumina, oxidation resistance and corrosion resistance. As a result, the clogging of the nozzle and the oxidation of the carbon is effectively prevented. The reduction of the casting cost of a molten steel and the cost of the refractories as well as the stable long-time casting of the steel is enabled. A large contribution is thus made to the improvement in the productivity of irons and steels. |
