The effects of rolling deformation on Al-27%Si alloys prepared by powder metallurgy for electronic packaging applications

Al-27%Si alloys were prepared with 99.9% pure aluminium powder and 99.9% pure silicon powder through powder metallurgy. The sintered experimental alloy ingots were homogenized at 773 K for 2 h and hot rolled to sheets with 3 mm in thickness with several rolling passes. The results show that silicon grains were broken down to streamline with small size ranging from 5 μ m to 40 μ m after rolling. Thermal conductivity, relative density and gas-tightness of Al-27%Si alloys were increased to 143.8W/m·K (28°C), 99.3%, 2×10^-8Pa· m³/S through rolling deformation. There was no significant change with coefficient of thermal expansion of Al-27%Si alloy. Rolling deformation can decrease the amount of holes in Al-27%Si alloy prepared through powder metallurgy.