In the present study the effect of addition of some cramic particles (SiC, Al2O3 and YSZ) with various concentrations of 5, 10 and 15wt. % on microstructure alteration and solidification characteristics of Al-18%Mg2Si composite is investigated using optical microscopy and cooling curve thermal analysis (CCTA). The results show that addition of ceramic particles leads to change of the nucleation temperature of primary Mg2Si particles. Furthermore, SiC with 15wt. % concentration illustrated the highest refinement effect on both primary and eutectic Mg2Si particles compared to Al2O3 and YSZ reinforcements. Unexpectedly, increase of the level of Al2O3 resulted in disappearance of primary Mg2Si. Moreover, YSZ addition did not reveal a considerable effect on refinement of eutectic Mg2Si particles.
