ROLE OF THE PRIMARY PHASE ON EUTECTIC SOLIDIFICATION OF Al-Si ALLOYS.

Abstract

Studies of the initial stage of Al-Si eutectic solidification were carried out by thermal analysis. It was found that silicon crystals are usually nucleated on the surface of aluminum crystals by small undercooling, whereas aluminum crystals are not easily nucleated on the surface of silicon crystals. This finding can be explained in terms of relative interfacial energies for boundaries of liquid-primary, liquid-secondary, and primary-secondary phases.