Three-Dimensional Simulation of Macrosegregation in a 36-Ton Steel Ingot Using a Multicomponent Multiphase Model

A multicomponent multiphase solidification model has been developed to predict macrosegregation of steel ingots in three dimensions. The interpenetrating continua of liquid melt and solid grains is coupled with air for the mass, momentum, concentration, and heat transfer. Interfacial solute constraint relationships are derived to close the model by solving the solidification paths of multicomponent alloy. The upward unidirectional solidification case of a ternary Al-6.0 wt.%Cu-1.0 wt.%Si alloy is taken as a basic validation. Predictions have well captured the inverse segregation profiles induced by shrinkage during solidification. Then, the model is applied to a 36-ton steel ingot, which was experimentally investigated by temperature recording and concentration analysis. Predictions have reproduced the macrosegregation patterns in the measurements. Confidence levels of current predictions compared to the concentration measurements have been presented. General good agreements are exhibited in quantitative comparisons between measurements and predictions of carbon and sulfur variations along selected positions.