Al-Si合金超高压凝固过饱和固溶体的时效组织与性能

M-9．21％Si亚共晶铝硅合金在5．5GPa高压下凝固，获得接近单-α相的超高过饱和固溶体．对超过饱和固溶体进行时效处理，获得了弥散分布的细颗粒Si相，合金的性能有非常大的提高．分析了时效处理温度和保温时间对析出组织的影响．高压凝固获得超高过饱和固溶体后进行时效处理，有可能成为制备某些特殊材料的新方法．

Precipitated structure and properties of Al-Si alloy extended solution solidified at high pressure

Hypoeutectic Al-9. 21% Si alloy was solidified under a pressure of 5. 5 GPa and an altra-high supersatuated solid solution with nearly single a phase has been attained. The solid solution then under went ageing treatment and dispersed and fine Si particles were formed, resulting in an obvious improment in mechanical properties of the alloy. The effect of ageing time on the precipitation micrstructure were also analyzed in the paper. It might become a new method for preparing some special materials to attain ulltrahigh supersatuated solid solution by using high pressure solidification first and then to carry out ageing treatment.