Method for continuous casting of steel containing rare earth metal

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PROBLEM TO BE SOLVED : To provide a continuous casting method for rare earth metal-containing steel which prevents the sticking of REM-based inclusions having a high melting point and a high specific gravity to the inner wall of an immersion nozzle stably over a long period. SOLUTION : There is provided the continuous casting method for rare earth metal-containing steel in which molten steel is poured into a mold using the immersion nozzle in a continuous casting apparatus. In the method, at least the molten metal flow passage working surface of the immersion nozzle is composed of a refractory satisfying that an MgO content is 60 to 85 mass% and the reduced value of a carbon content is 15 to 40 mass%, wherein the total of the MgO content and the reduced value of the carbon content exceeds 85 mass%, and continuous casting is performed under the condition that the rare earth metal content [%REM] and sol. Al content [%Al] in the molten steel and the MgO content (%MgO) in the refractory satisfy inequality : [%Al]/[%REM]×(%MgO)≥13. The total content of Ce, La, Pr and Nd in the cast rare earth metal-containing steel is 0.001 to 0.1 mass%. COPYRIGHT : (C)2012, JPO&INPIT