2003 Volume 43 Issue 7 Pages 1095-1099
Numerical simulation of three-dimensional dendritic growth is studied by using a macro-micro coupled method and a capturing liquid method. The dendritic growth is controlled by the solution of the phase field equation. Since it is difficult to compute the microstructure of a whole sample, a scheme is adopted that the temperature field is calculated on the whole sample, while the microstructure computation is carried out by selecting a macro-cell in the casting. Under the condition of not changing the Phase-field Model, a calculating method is advanced, which captures the liquid cells into the interface cells. In that method, every calculated micro-cell is endowed with a variable which identifies whether the cell is in the interface region and the phase field equation is only solved for the cells in that region. When the dendrite grows, the method captures the liquid cells into the interface ones and pushes the interface region forward. For the captured liquid cells, the values of the phase variable are modified. We apply the calculating method to accelerate the calculating speed, and realize the simulation of three-dimensional single grain and multiple grains for aluminum alloy. The simulation results are compared with those obtained experimentally.