A model for equiaxed eutectic solidification with melt convection and solid-phase transport

This paper presents a method to track microstructural evolution during eute ctic solidification using a coupled fluid flow - mass transport model. The continuum formulations were used to describe the macroscopic transports of mass, energy, and momentum, associated with the microstructural evolution, for two-phase systems. It was assumed that the liquid flow is driven by the rmal and solutal buoyancy, as well as solidification contraction. The eutec tic cell (grain) of cast iron was assumed to have a spherical morphology, T he microstructural model includes the gray-to-white eutectic transition and the influence of microsegregation on the eutectic temperature. A continuou s nucleation law was used in calculation. Rules for grain movement have bee n developed to track the nucleation, growth and movement of grains because of melt convection. Three test cases are discussed to demonstrate the influ ence of melt convection and solid phase transport on microstructure evoluti on for eutectic cast iron.