The Effects of Electromagnetic Stirring on Solidification Structure of Continuously Cast SUS43O Stainless Steel Slabs

Abstract

Effects of electromagnetic stirring on the solidification structure of continuously cast SUS430 slabs were investigated to reduce the ridging of cold-rolled sheets by grain refinement of the solidification structure. The following results were obtained: (1) The area in which equiaxed crystals form increases with increasing stirring intensity and decreasing superheat (4T) of molten steel. The most suitable stirring mode is the alternate stirring. The effect of 4T can be moderated by lowering the position of the stirrer, but the ratio of equiaxed crystals decreases in this case. Appropriate conditions for obtaining a ratio of equiaxed crystals over 60% were determined. (2) Ridging is reduced as the ratio of equiaxed crystals increases. Stable ridging obtained for 50% or more equiaxed crystals is the same as that of steel sheets rolled from ingots.

Optimisation of Electromagnetic Stirring in Steel Billet Caster by Using Image Processing Technique for Improvement in Billet Quality

“…3) Optimum stirring intensity facilitates homogenization of composition and temperature subsequently minimization of macrosegregation. 4) Rotational velocity generated by a rotary EMS depresses the position meniscus, thereby decreases the effective immersion depth of the submerged entry nozzle (SEN) and gives rise to mould flux/slag en-…”

“…Therefore, SEN immersion depth should be optimum for ensuring defect free casting. 4) Magnetic field induced by EMS changes the shape of the liquid pool from a tall inverted pyramid to a truncated shape which changes the solidification direction from one of directionally inwards to predominantly upwards from the bottom of the pool. It follows that such a relatively flat bottom will provide a strand cast product relatively free of centre defects.…”

“…It follows that such a relatively flat bottom will provide a strand cast product relatively free of centre defects. 4,5) …”