| 摘要 |
PROBLEM TO BE SOLVED: To provide a continuous casting method for steel where, utilizing a static magnetic field more excellent in flowing control than the conventional static magnetic field, the flowing of molten steel in a mold is braked, thus the distribution in the width direction of a slab at a solidification completion position is controlled so as to be more precisely compared with the conventional one, in this way, the effect of light rolling reduction is sufficiently made to appear, and a slab in which central segregation is slight is cast. SOLUTION: First electromagnets 19, 20 applying static magnetic fields are split into two in the width direction of a mold with the installing position of an immersion nozzle 4 or the vicinity thereof as a boundary, and are arranged so as to be confronted with the back face of the mold, further, between the mold and the respective first electromagnets, second electromagnets 21 to 26 applying static magnetic fields are arranged in parallel to the width direction of the mold by two or more per first electromagnet, static magnetic fields are applied to the molten steel in the mold in such a manner that, regarding the respective first electromagnets and the second electromagnets, magnetic field intensities and polarities are independently controlled, and further, the slab is subjected to rolling reduction at a rolling reduction speed within the range of 0.6 to 1.5 mm/min from the point of time at which the solid phase ratio in the central part of the thickness in the slab is≤0.4 at least to the point of time at which the solid phase ratio in the central part of the thickness in the slab reaches≥0.7. COPYRIGHT: (C)2011,JPO&INPIT |
