3D MICROSTRUCTURE SIMULATION OF Al-Si/SiCp COMPOSITES FOR STIR CASTING
搅拌铸造SiCp/Al-7.0%Si复合材料的三维微观组织模拟

The microstructure of SiC particle reinforced A1-7.0%Si (mass fraction) composite prepared by stir casting was simulated by a modified cellular automaton method coupled with finite difference method,and 3D mathematical and numerical models under normal solidification condition were established including macro heat transfer,nucleation,equiaxed dendrite growth and particle pushing.The effects of particle volume fraction on macro heat transfer,composite microstructure and particle distribution were studied.The simulated results can clearly show the evolution of the microstructure of composite and particle clustering phenomena caused by particle pushing,which are in good agreement with the experimental ones.With the increase of SiC particle volume fraction, solidification time is decreased,composite matrix grains are refined and particles distributed more uniformly.