Study on the metallurgical function of mold electromagnetic stirring in continuous casting bloom

Abstract

The metallurgical function of mold electromagnetic stirring(M-EMS) was investigated by simulation according to the following factors: flow field, temperature field, solidification, removal of inclusions, slag entrainment, and macrosegregation. When the current intensity increased from 0 A to 490 A, the rotational flow induced by M-EMS enhanced gradually, and the impinging effect of jet flow on the solidification front decreased obviously. The average speed on the top surface increased from 0.015 m/s to 0.038 m/s. The temperature of the molten steel was more uniform, and the temperature on the top surface decreased from 1788.5 K to 1785.9 K. The depth of depressions induced by the jet flow decreased from 6.1 mm to 0.7 mm. When the current intensity of M-EMS was 390 A, the removal fraction of inclusions was the highest. When the current intensity of M-EMS was 0 A, no slag entrainment occurred. With the current intensity of M-EMS increasing from 290 A to 490 A, the net slag entrainment rate was 0.003, 0.013, and 0.047 kg/s. When the current intensity of M-EMS increased from 0 A to 490 A, the minimum carbon content of negative segregation in the subsurface of the bloom worsened from 0.176% to 0.167%. For the bloom CC process, the M-EMS scheme should be weak or no M-EMS to decrease the occurrence of slag entrainment and improve the negative segregation in the subsurface of the bloom.