Abstract: Light weight high-silicon aluminum alloys are used for electronic packaging in the aviation and space-flight. Al-30Si and Al-40Si are fabricated with air-atomization and vacuum canning hot-extrusion process. Material density, thermal conductivity, hermeticity and thermal expansion coefficient are also measured, and the relationship of extrusion temperature and properties are obtained. Experimental results show that the density of high-silicon aluminum alloys prepared with the method is high to 99.64% of the theory density, and it increases with elevating extrusion temperature, at the same time, thermal conductivity which varies between 104~140 W/(m·K) with the extrusion temperature and thermal expansion coefficient also increases, but it is within 13×10–6(at 100 ℃), and the her-meticity of the material is high to 10–9.

Key words: Hot extrusion, Thermal conductivity, Vacuum canning, Al-Si alloy, Electronic package, Gas sealed, Rapid solidification