Numerical Investigation on Grain Structure of Magnetic-Controlled Electroslag Remelted Ingot Based on CAFE and Equivalent Treatment Method

A transient two-dimensional axisymmetric model is developed to investigate the influence of the applied transverse static magnetic field (TSMF) on the grain morphology of the electroslag remelted (ESR) ingot. The cellular automata-finite element (CAFE) technique is employed to elucidate the nucleation and growth of the grains. Moreover, an equivalent treatment method by adjusting the effective thermal conductivity is introduced to model the effect of the electromagnetic vibration (EMV) generated by the applied 0.05T TSMF on the temperature distribution. The close correspondence between the experimental data and the simulation outcomes demonstrates the validity and reliability of the computational model. The results show that with the effective thermal conductivity increasing from \(\eta \) $\eta$ to \(3\eta \) $3\eta$ , the proportion of equiaxed grain increases from 25.1 to 48.7 pct and the grains get refined. Furthermore, the increase in effective thermal conductivity correlates with a decrease in both the local solidification time (LST) and the second dendrite arm spacing (SDAS) at the central region, suggesting a finer microstructure of the ingot. In addition, as the effective thermal conductivity increases, a substantial decrease in the maximum depth of the metal pool is observed, reducing from 53.9 to 19.4 mm, which should be conductive to microstructure refinement and macrosegregation alleviation.