摘要
采用富镧混合稀土对过共晶Al-24%Si合金进行变质处理,对其微观组织和力学性能进行了研究。实验结果表明:富镧混合稀土不但能有效变质合金中的初晶硅,使其尺寸减小到40μm左右,形状多为规则的多边形;而且对共晶硅的细化更为明显,在初晶硅周围的共晶组织多为短杆状,部分则呈颗粒状,合金经变质后力学性能得到了明显提高。同时,初步探讨了混合稀土的变质机制。
The influences of RE on the microstructure and mechanical properties of hypereutectic Al-24%Si alloy were investigated. Microstructure was examined by SEM.The results show that the addition of La has strong modification effect on the microstructure of hypereutectic Al-24%Si alloy. The average grain size of primary Si phase can be reduced to 40 μm, meanwhile, its modification effect on the eutectic silicon is more obvious, and the eutectic silicons can be transformed into the fine lamella ones. The mechanical properties are improved. The modification mechanism was also discussed.
出处
《热加工工艺》
CSCD
北大核心
2009年第5期33-35,共3页
Hot Working Technology
关键词
混合稀土
变质
微观组织
力学性能
变质机制
rare earths
modification
microstructure
mechanical properties
modification mechanism
