METHOD COMPRISING CONTINUOUS CASTER PROVIDING STEP, MOLTEN STEEL INTRODUCTION STEP AND MOLTEN STEEL CASTING STEP TO MANUFACTURE ULTRA-LOW CARBON STEEL SLAB

摘要

PURPOSE: To provide an ultra-low carbon steel slab manufacturing method capable of obtaining a slab excellent surface quality event at a high casting rate of 2.0 m/min or more without any post-treatment process such as scarfing. CONSTITUTION: The method for manufacturing an ultra-low carbon steel slab comprises: a step of providing a continuous casting apparatus comprising a casting space having a short-side length D of about 150 to 240 mm, and a mold equipped with a submerged entry nozzle having at least one or more discharge spouts, wherein the discharge spouts have a lateral width d in such a way that a ratio of D/d is in a range of about 1.5 to 3.0; a step of introducing molten steel into the mold through the submerged entry nozzle; and a step of casting the molten steel at a casting rate of about 2.0 mm/min or more by the continuous casting apparatus to manufacture ultra-low carbon steel slab having a carbon content of about 0.01 mass% or less.