METHOD OF CONTINUOUS CASTING OF MULTI-LAYER SLAB.

摘要

Two kinds of molten steel are poured into a mold for continuous casting. A DC magnetic flux directed to intersect the thickness of poured contents (corresponding to the thickness of a slab) is provided when the mold is positioned at a predetermined height. Molten steel is fed at positions above and below a static magnetic zone as a boundary which is formed by said DC magnetic flux and divides an inner space of the mold into top and bottom ones along the vertical direction, that is, the casting direction. Where the difference (Wp) between the density p<5> of molten steel to be fed above the static magnetic zone for forming the outer layer of a slab and the density p<6> of molten steel to be fed below said zone for the inner layer is Wp = p<5> - p<6>, the DC magnetic flux density (tesla) is adapted to satisfy the relations expressed by the following formulas: a) when Wp < 0, B / Ä2.83 x (Wp)<2> + 1.68 x Wp + 0.30Ü; b) when 0 & Wp, B / Ä20.0 x (Wp)<2> + 3.0 x Wp + 0.30Ü.