Simulation of dendritic growth in solidification of Al-Cu alloy by applying the modified cellular automaton model with the growth calculation of nucleus within a cell

Rather than designated directly as solid if the micromesh (or cell) larger than a nucleus is chosen as the nucleation site, the growth of a nucleus in the cell is considered in the application of the modified cellular automaton model to simulate the evolution of dendritic microstructures in the solidification of Al-Cu alloy. The growth velocity of a nucleus or a dendrite tip is calculated according to the KGT (Kurz-Giovanola-Trivedi) model, which is the function of the undercooling. In this study, the dendritic microstructures, such as the free dendritic growth in an undercooled melt and the dendritic growth in the directional solidification, are simulated with the modified growth algorithm in the nucleation cell. The simulated results for the temporal and final morphologies are shown and are in agreement with the experimental ones.