| 摘要 |
PROBLEM TO BE SOLVED: To restrain the constraction and the clogging of an inner hole due to non-metallic inclusion of an alumina, etc., and to stably cast an aluminum- killed steel by forming the surface layer part of the inner layer part of a nozzle, in which molten steel flows of refractory having specific chemical component composition. SOLUTION: The inner hole surface layer part 2 being in contact with the molten metal in the continuous casting nozzle 10, is formed by adding binder to the composition of 15-60 wt.% aggregate consisting of alumina or essentially of alumina and having >=1800 deg.C m.p. and the balance agalmatolite and kneading, and fired under non-oxidizing atmosphere. Further, the agalmatolite having <=250 μm grain diameter in <=60 wt.% blending ratio in the total agalmatolite, is used. Semimelting temp. of the agalmatolite is about 1500 deg.C and the agalmatolite is melted on the working surface being in contact with the molten steel and glassy film is formed and therefore, the structure of the working surface is smoothened and further, the enclosure of the air through the refractory structure is restrained with the glassy film. |
