A 2D STOCHASTIC MICRO-MACRO MODEL OF EQUIAXED EUTECTIC SOLIDIFICATION

We propose a model of equiaxed eutectic solidification that couples ma croscopic heat diffusion with a microscopic description of nucleation and growth of the eutectic grains. The heat equation is solved numeric ally by means of an implicit finite difference method. The evolution o f solid fraction is deduced from a stochastic model of nucleation and growth which uses the local temperature (interpolated from the FDM mes h) to determine the local grain density and the local growth rate. The model predicts the evaluations of both temperature and solid fraction at any point of the sample. Moreover, a realistic appearance of the r ecalescence on the cooling curves, as well as a detailed picture of th e microstructure, are predicted. We apply the model to the solidificat ion of grey cast iron.