| The manufacturing of high quality steel products will be possible only if the steel coming out of steelmaking furnaces is of acceptable cleanliness. Deleterious effects caused by residual elements, such as copper, must be identified in order to keep the effects within acceptable limits. In this regard, understanding the mechanism of microsegregation during solidification of steel is essential.; This research establishes an estimate of copper microsegregation in low carbon steels by performing a finite element analysis of heat flow and coupling with the Giovanola-Kurz model for copper redistribution in steel. It is necessary that the heat flow calculations and the microsegregation calculations are coupled because the rate of latent heat liberation is affected by the solute redistribution process, while the solute redistribution process depends on the cooling rates.; The results deduced from the model demonstrate the effect of the initial concentration of copper, Peclet number, dendrite tip radius, dendrite tip concentration, and dendrite tip temperature in the microsegregation of copper in the steel.; At low velocities, the Peclet number that characterizes the response of the solidification interface instability sharply decreases with a decrease in interface velocity. The Peclet number is lower for higher amounts of copper in the steel.; The dendrite tip radius is infinite at extremely low interface velocities indicating a transformation to a planar interface. In the dendritic regime, the tip radius decreases with an increase in the interface velocity. In a certain velocity the dendrite tip radius decreases with the increment of copper in the steel. Therefore, by having a smaller radius, there is more chance for the diffusion of copper in steel and, eventually, having less copper microsegregation.; The dendrite tip concentration increases with an increase in the interface velocity. The amount of copper in the dendrite tip increases with an increase in the interface velocity; and, at higher initial percentage of copper in steel, the amount of copper increment is higher.; The dendrite tip temperature decreases with an increase in the interface velocity and is lower for higher amounts of copper in the steel.; The results of this study also show that pouring temperature and, particularly, casting velocity of steel billet play an important role in the microsegregation of elements in steel. By selecting the pouring temperature and the casting velocity as low as possible, a lower amount of copper microsegregation can be achieved. |
