連続鋳造鋳型内における亜包晶炭素鋼の不均一凝固の制御
1992 年 78 巻 1 号 p. 105-112
詳細
1992 年 78 巻 1 号 p. 105-112
Surface cracks tend to occur in continuously cast slab of hypoperitectic carbon steels. The surface cracks are originated by an uneven solidified shell formation in the continuous casting mold. Mechanism of uneven solidified shell formation at the initial stage of solidification was investigated by dipping of water cooled chill plates in the molten steel. The dip test showed that, (1) the shell of hypo-peritectic carbon steel has a hexagonal depression pattern and these depressions form air gap between the shell and the chill plate and results in the uneven solidified shell formation, (2) the chill plate with a fixed interval lattice grooves was most effective to prevent the uneven solidified shell formation. Nextly, the casting tests using a small-scale continuous caster were performed to investigate the measures for prevention of the uneven solidified shell formation. The mold with a controlled uneven heat extraction method was essential to form the even solidified shell at the initial stage of solidification.
