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 al...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.展开更多
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)
文摘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.