IMMERSION NOZZLE FOR CONTINUOUS CASTING

摘要

PROBLEM TO BE SOLVED: To reduce casting piece crack during casting of a sub-peritectic steel.SOLUTION: The invention relates to an immersion nozzle for continuous casting of a sub-peritectic steel using a zirconia-carbon fibrous material as a powder line material. In the immersion nozzle, the zirconia of equal to or more than 100μm on the powder line part is made to MgO stabilized zirconia. The MgO stabilized zirconia is stabilized zirconia or partial stabilized zirconia including 0.5-10 mass% of a MgO content. The zirconia-carbon fibrous material comprises a content of 70-95 mass% of a zirconia raw material and 5-20 mass% of a content of a carbon raw material when total sum of the zirconia and carbon is 100 mass%. Therefore, occurrence probability of casting piece crack during casting of the sub-peritectic steel can be significantly reduced.