Application of CAFÉ Method on Microstructure Simulation of Semi-solid Al–7%Si Alloy

Abstract

Nucleation and growth of grains mainly happen in the stage of slurry preparation period during semi-solid die-casting process. The microstructure of slurry can directly influence the grain morphology and the mechanical properties of products. Thus, the prediction of semi-solid slurry microstructure is of vital importance for process optimization and products mechanical properties improvement. Cellular Automaton Finite Element (CAFE) method was adopted in this study to simulate the microstructure evolution of Al–7%Si alloy during semi-solid slurry preparation by using thermal equilibrium process. The models for interface heat transfer coefficient (IHTC) between slurry and crucible, and nucleation parameters under different pouring temperatures are the most important factors in this CAFE method, and they are the main tasks in this study. The results demonstrated that the cellular automaton model used in this article could directly display the details of microstructure evolution during slurry preparation process. The nucleation and growth patterns of grains were also analyzed according to the simulation results under different pouring temperature conditions. The control mechanism of thermal equilibrium process was obtained and it provided solid foundation for the popularization and application of thermal equilibrium semi-solid slurry preparation technique.