Solute redistribution and macrosegregation in continuous casting slab of carbon steel during solidification process

Based on the modified Scheil model of solute redistribution,the effects of solidification rate,molten steel flow,and alloy composition on solute macrosegregation during the solidification of carbon steel continuous casting billet are calculated and analyzed. The formation mechanism of "white band" segregation under the condition of electromagnetic stirring is also involved,and some practical countermeasures to restrain the central segregation are suggested. The results show that the modified Scheil model can be applied to predict and analyze the macrosegregation of casting slab effectively. The ratio vx/R of the flow velocity of molten steel to solidification rate has decisive formations of segregation such as linea, V,and "white band" types. It is an effective way to select sufficient termina cooling and reasonable electromagnetic stirring in order to decrease macrosegregation in the slab. The concept of the chaacteristic distance of solute enrichment layer can drastically simplify the calculation of solute redistribution at the solid/liquid interface of various elements in cabon steel.