A multiphysics coupled model integrating molten‐steel flow, solidification heat transfer, solute transport, and electromagnetic forces was developed to study macrosegregation in 180 mm× 220 mm medium‐carbon, sulfur‐bearing F38MnVS continuous‐casting billets. The model was validated against measurements of the electromagnetic field, billet‐surface temperature, and solute (C and S) distributions. Simulations show that mold curvature induces asymmetric flow and temperature fields; ignoring curvature, therefore biases the predicted mixing and solidification behavior. mold electromagnetic stirring (M‐EMS) enhances recirculation and mixing, improving flow uniformity. While increasing M‐EMS current accelerates the growth of the solidified shell, it exacerbates both subcutaneous negative segregation and center‐positive segregation. For final EMS (F‐EMS), higher frequency lowers the local temperature and increases solid fraction, accelerating solidification. An appropriate electromagnetic stirring frequency helps alleviate the centerline macrosegregation. However, an excessively high stirring frequency can aggravate this phenomenon due to severe dendrite fragmentation. The synergetic application of M‐EMS and F‐EMS effectively suppresses solute enrichment and enhances overall billet quality. Through the synergistic use of M‐EMS (300 A, 3 Hz) and F‐EMS (400 A, 8 Hz), this study successfully minimized macrosegregation and lowered the centerline segregation indices of C and S to 1.19 and 1.081, respectively.
Qiu et al. (Thu,) studied this question.