Optimization of Glass Forming Ability of Al-Ni-Si Alloys by a Thermodynamic and Kinetic Approach

This study reports the glass forming ability (GFA) of Al-Ni-Si alloys with selected compositions based on atomic packing efficiency and driving force criteria. Higher GFA was observed in the Al-rich lower liquidus temperature regions of the Al-Ni-Si system indicating that these compositions exhibit a lower driving force for crystallization. Five glassy alloys that were calculated to consist of densely packed atomic short-range ordering were found to retain an amorphous structure upon copper mould casting. The result of GFA in the Al-Ni-Si system provides a novel approach to develop new metallic glasses considering both the thermodynamic stability and sluggish crystallisation kinetics through efficient packing.