中国铸造2009，Vol.6Issue(2)：129-132,4.
Microstructure variation and growth mechanism of hypoeutectic Al-Si alloy solidified under high pressure
Microstructure variation and growth mechanism of hypoeutectic Al-Si alloy solidified under high pressure
摘要
Abstract
The microstructure of hypoeutectic Al-9.21wt.%Si alloy solidified under 5.5 GPa was studied. The results show that the solidification microstructure is refined. The primary a phase is the extended solid solution.The solid solubility of Si in a phase is up to 8.26wt.%. The growth mode of the a phase is cellular, and this cellular growth mechanism is interpreted in terms of the decrease of the diffusivity and the extended solid solution under high pressure. By calculation, it can be known that the the diffusivity of solute in the liquid under normal pressure is as high as two hundred times that under high pressure. The microhardness of the hypoeutectic Al-Si alloy solidified under high pressure is higher than that of solidified under normal pressure. After annealing, Si precipitates from the solid solution, the microhardness of the alloy decrease, but, still higher than that of solidified under normal pressure.关键词
Al-Si alloy/high pressure solidification/extended solid solution/cellular growthKey words
Al-Si alloy/high pressure solidification/extended solid solution/cellular growth分类
矿业与冶金引用本文复制引用
Zhang Guozhi,Yu Xifeng,Liu Xinggang..Microstructure variation and growth mechanism of hypoeutectic Al-Si alloy solidified under high pressure[J].中国铸造,2009,6(2):129-132,4.基金项目
This project is supported by the National Natural Science Foundation of China(grant No.59571040) （grant No.59571040）
