DEVELOPMENT OF HIGH-STRENGTH HYPEREUTECTIC Al-Si ALLOYS BY NANO-REFINING THE CONTITUENT SI PHASES

摘要

Among the structural light weight materials, Al-Si alloys have established itself as the most widely used Al-alloys for aerospace and automotive applications. Our recent efforts have demonstrated that it is possible to develop primary Si-phase free hypereutectic Al-Si alloys by a casting method. In the continuation of this effort, an Al-17wt%Si alloy that has a microstructure in which silicon phase assumes nano sized fibrous morphology has been developed by directional casting. The fabrication and characterization of these unique Al-Si alloys are presented. The mechanical properties of this alloy based on first principle, are also discussed.