铸造技术2013，Vol.34Issue(3)：259-262,4.
Bi对过共晶Al-15Mg2Si合金Mg2Si相的变质作用
Effect of Bi Modification on Mg2Si Phase in Hypereutectic Al-15Mg2Si Alloy
摘要
Abstract
The influence of Bi additions on the microstructure of hypereutectic Al-15Mg2Si alloy was investigated by XRD,SEM and EDS,and the modification mechanism was analyzed.The results show that the proper amount of Bi has a significant modification effect on both primary and eutectic Mg2Si in the alloy.When 1.0％Bi is added,the morphology of primary Mg2Si changes from dendritic to polyhedral shape,its average grain size significantly decreases from 70 μm to 6 μm; at the same time,the eutectic Mg2Si fiom flake-like to very short fibrous or dot-like.The modification mechanism may be related to the decrease of the interfacial tension between the Mg2Si phase and Al liquid and the composition supercooling caused by the segregation of Bi at the front of the solid/liquid interface of Mg2Si during solidification.关键词
过共晶Al-Mg2Si合金/Bi/变质/初生Mg2Si/共晶Mg2SiKey words
hypereutectic Al-Mg2Si alloy/ Bi/ modification/ primary Mg2Si/ eutectic Mg2Si分类
矿业与冶金引用本文复制引用
司颐,王喆,武晓峰..Bi对过共晶Al-15Mg2Si合金Mg2Si相的变质作用[J].铸造技术,2013,34(3):259-262,4.基金项目
辽宁省教育厅重点实验室资助项目(20060394) （20060394）
