摘要
研究了稀土元素铈对过共晶Al-18Si合金的变质效果。试验结果表明,铸件中初生硅的尺寸随着铈含量的增加而减小,同时铸件中共晶硅的变质效果随着铈含量的增加而更加明显,初生硅附近的共晶组织其变质效果远不如远离初生硅的显著;相应的力学性能提高到一定值后,基本保持不变。本文还利用热力学以及扫描电镜及其能谱分析了稀土元素的变质机理。
There were many different views about the modification mechanism of rare earth element on the microstructure, especially on the primary silicon of hypereutectic Al-Si alloy. In this paper, the modifying effect of the rare earth cerium (Ce) on the hypereutectic Al-Si alloy had been studied by using of Optical Microscope and all-purpose material equipment. The results of experiments showed that the size of primary silicon in castings decreased with the increase of Ce content in the melting. Meanwhile, the modifying effect of eutectic silicon becomes more and more significant. The effect on the eutectic silicon away from primary silicon was more obvious than that on the eutectic silicon close to the primary silicon. The mechanical properties were improved to a certain level, then kept stable. The modification mechanism is analyzed by means of thermodynamics analysis and Scanning Electron Microscope Equipped with Energy Dispersive Analysis of X-Ray.
出处
《铸造》
CAS
CSCD
北大核心
2005年第12期1265-1268,共4页
Foundry
关键词
稀土元素
过共晶AL-SI合金
力学性能
变质机理
热力学分析
rare earth element
hypereutectic Al-Si alloy
mechanical property
modificationmechanism
thermodynamics analysis