Production manner null of extra mild steel continuous casting

摘要

PROBLEM TO BE SOLVED: To provide a method for producing a continuously cast billet of extra- mild steel which does not develop the clogging of a pouring nozzle at the time of pouring, the scum flaw, Al spills and blow hole even in the case of using no vacuum degassing treatment, and applies the open pouring. ;SOLUTION: In the producing method of the continuously cast billet of extra- mild steel by executing the open pouring without using an immersion nozzle at the time of pouring the molten steel into a continuous casting mold from a continuous casting tundish, the molten steel in the tundish is composed of, by weight, 0.01-0.08% C, 0.001-0.10% Si, 0.001-0.50% Mn, 0.003-0.008% Ti, 0.005-0.0020% Ca and ≤0.005% Al and the balance Fe with inevitable impurities, and further Al of (0.08/[%Ti]) g to 60 g per ton of molten steel is added into the steel in the continuous casting mold.;COPYRIGHT: (C)2000,JPO