Three-Dimensional Phase Field Simulation of Dendritic Morphology of Al-Si Alloy

Based on the Karma thin interface phase-field model with the solid diffusivity, the effects of interface width and thermal noise on the dendrite growth behavior in undercooled melt of Al-Si alloy were studied by a three-dimensional adaptive meshing method. The simulation results show that with the increase of interface width, the complexity of dendrite morphology, the dendritic tip velocity and the solute concentration at the tip liquid phase decrease. With the increase of thermal noise amplitude, the dendritic tip changes slightly, and the number and asymmetry of secondary dendrites located on both sides of the dendrite increase.