MICROSTRUCTURE SIMULATION OF Al-Si/SiCp COMPOSITES WITH PARTICLE PUSHING MODEL
用颗粒推移模型模拟Al-Si/SiCp复合材料微观组织

The microstructure of SiC particle reinforced Al-7.0%Si (mass fraction) composite prepared by stir casting was simulated by a modified cellular automaton method coupled with finite difference method and two-dimensional models under normal solidification condition including macro heat transfer, nucleation, equiaxed dendrite growth and particle pushing. The effects of different casting processes on composite microstructure and particle distribution were analyzed. The simulated results can clearly show the evolution of the microstructure of composite and particle clustering phenomena caused by particle pushing. The simulated results are in good agreement with the experimental results. Grain size is smaller and particle distribution is more uniform for metal mould casting than sand mould casting.