Effects of electromagnetic stirring on fluid flow and temperature distribution in billet continuous casting mould and solidification structure of 55SiCr

Abstract

The optimal combination of current intensity and frequency of mould electromagnetic stirring (M-EMS) in continuous casting billet was a crucial compromise for improving inner quality of cast billet such as reduction in center segregation and porosity of medium-high carbon steel. In the present study, a decoupled three-dimensional mathematic model of electromagnetic field, fluid flow and heat transfer in continue casting billet mould with EMS has been developed, and the effects of current intensity and frequency on the system were also discussed. In addition, the industrial trials were carried out to investigate the magnetic field characteristics in the mould with M-EMS and the influence of M-EMS on the solidification structure of 55SiCr. According to the calculations and analysis, the optimal combination range of current intensity and frequency was 300–320 A and 3–4 Hz, respectively. The results showed that inner quality in as-cast billet of 55SiCr has been improved significantly with optimal parameter of 320 A and 3 Hz. For instance, central equiaxed zone increased from 19% to 33%, the center carbon segregation ratio decreased from 1.13 to 1.05 as well as center porosity has nearly disappeared.

Effect of the Gap Between Copper Mold and Solidified Shell on the Fluid Flow in the Continuous Casting Strand with Mold Electromagnetic Stirring

“…The benefits of M‐EMS were widely recognized by metallurgists and industries: enlarging the equiaxed crystal zone, reducing center segregation and porosity, intensifying the fluid flow, heat, and mass transfer near the meniscus, helping the removal of inclusions from the molten steel. Many studies investigated the effect of M‐EMS on the inner quality of continuous casting (CC) blooms including center segregation, center porosity, and equiaxed crystal ratio by industrial trials. In the past decades, the effect of M‐EMS on fluid flow, temperature distribution, species transfer, and removal of inclusions was numerically simulated .…”

Numerical and experimental investigation of solidification structure evolution and reduction of centre segregation in continuously cast GCr15 bloom

“…In the present study, a 5-strand bow type bloom caster with a section size of 220 × 260 mm Assumptions, the initial condition and boundary conditions have been described in detail in author' research [14]. In addition, the model as well as the whole subsequent discussion is based on the hypothesis of heat transfer in the solid and liquid steel by conduction only and that convection at the solid-liquid interface is neglected.…”

Electromagnetic torque detecting for optimization of in-mould electromagnetic stirring in the billet and bloom continuous casting

“…As can be seen from Equation ( 4), electromagnetic torque mainly depends on parameters B 2 ω or billet structural parameter r 1 4 L of the electromagnetic stirrer.…”