2016 年 102 巻 3 号 p. 157-163
An analysis for solute redistribution and the macrosegregation during alloy solidification process under fluid flow were carried out by using a one dimensional cellular automaton method. The effect of fluid flow on the solute redistribution was incorporated as an eddy diffusion coefficient. Examination was carried out for the planar S/L interface solidification of a model alloy and the solidification of a Fe-0.6 mass%C alloy with mushy zone, respectivly. Steady state solidification was formed with no fluid flow condition for the planar S/L interface solidification. Macrosegregation was formed during the planar S/L interface solidification under the fluid flow, and the degree of the macrosegregation increased with increase in eddy diffusion coefficient. Two types of fluid flow, i.e. macroscale flow and micro scale flow were considered for the study of the solidification of the Fe-0.6 mass%C alloy with mushy zone. It was shown that the degree of the macrosegregation with micro scale flow was larger than that with macro scale flow. The effect of the limiting fraction of solid for flow in mushy zone was examined, and the degree of the macrosegregation in Fe-0.6 mass%C alloy was increased with increase in the limiting fraction solid for flow.
