Microstructure and phase compositions of as-cast Mg–3.9Zn–0.6RE(Gd,Y) alloy with different Gd/Y ratios  

作　　者：Yang Yang Kui Zhang Ming-Long Ma Jia-Wei Yuan 

机构地区：[1]State Key Laboratory for Fabrication and Processing of Nonferrous Metals,General Research Institute for Nonferrous Metals

出　　处：《Rare Metals》2015年第3期160-163,共4页稀有金属（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.51204020);the National Basic Research Program of China(Nos.2013CB632202 and 2013CB632205)

摘　　要：Mg-Zn-RE （Gd, Y） alloys with different Gd/Y atomic ratios were prepared by conventional casting, and the microstructure of the alloys was studied by multiple means. Icosahedral quasicrystal phases are observed in all alloys. The different Gd/Y atomic ratios affect the micro- structures of the alloys irregularly. The alloy with more Gd has large dendritic structure and more complicated phase composition which are composed of I-phase lamellar eutectic, W-phase divorced eutectic, Mg-RE cuboid par- ticles and Mg-Zn binary phases. Other two alloys show similar microstructures and phase compositions with very thin lamellar eutectics which distribute along the inter- dendritic region, and the lamellar eutectics are formed by I-phase and Mg. The element contents of the I-phases and Mg-RE phases are partially controlled by the Gd/Y atomic ratio.Mg-Zn-RE （Gd, Y） alloys with different Gd/Y atomic ratios were prepared by conventional casting, and the microstructure of the alloys was studied by multiple means. Icosahedral quasicrystal phases are observed in all alloys. The different Gd/Y atomic ratios affect the micro- structures of the alloys irregularly. The alloy with more Gd has large dendritic structure and more complicated phase composition which are composed of I-phase lamellar eutectic, W-phase divorced eutectic, Mg-RE cuboid par- ticles and Mg-Zn binary phases. Other two alloys show similar microstructures and phase compositions with very thin lamellar eutectics which distribute along the inter- dendritic region, and the lamellar eutectics are formed by I-phase and Mg. The element contents of the I-phases and Mg-RE phases are partially controlled by the Gd/Y atomic ratio.

关 键 词：Mg-Zn-RE alloy Icosahedralquasicrystalline MICROSTRUCTURE Atomic ratio 

分 类 号：TG292[金属学及工艺—铸造]