MOLD POWDER FOR CONTINUOUSLY CASTING MEDIUM CARBON STEEL CAST SLAB AND METHOD FOR CONTINUOUSLY CASTING MEDIUM CARBON STEEL CAST SLAB

摘要

PURPOSE: To provide mold powder for continuous casting which prevents the development of the longitudinal crack on a cast slab caused by the development of uneven solidified shell in a mold, and to provide a method for continuously casting medium carbon steel cast slab. ;CONSTITUTION: This mold powder for continuous casting has a compsn. containing essentially CaO and SiO₂ in a ratio CaO/SiO₂ (by wt.%) of 1.2-1.6 and 2-6wt.% in total of MgO+LiO₂. The molten powder is cooled at least to ≤400°C at 1500-2500°C/min cooling rate and solidified to measure the crystallizing ratio of the obtd. solidified powder. The cast slab containing carbon in the range of 0.08-0.16wt.% is produced with the continuous casting by using the mold powder for continuous casting having ≥50% evaluated crystallizing ratio.;COPYRIGHT: (C)1996,JPO