Effect of High-Energy Ball Milling to Powders on Microstructure and Physical Properties of Al-50Si Alloy

Al-50Si can be fabricated with a method in which air-atomization is followed by vacuum canning hot-pressing process. In order to improve the mechanical character and the physical property，the treatment of high-energy milling are used in the pretreatment of the powder of Al-50Si.The microstructure，density ,coefficient of thermal expansion are analyzed by scanning electron microscope(SEM) and thermal physical tester. It was found that the silicon grain was refined, the density and strength was improved when high silicon alloy powders were treated by high-energy ball milling.