摘要
Gadolinium （Gd） solubility in magnesium （Mg） matrix and precipitate composition in Mg-Gd binary alloys were investigated. The alloys containing different Gd contents （10 wt.%-35 wt.%） were employed to identify Gd solubility after annealing at different temperatures. It was confirmed that the maximum Gd solubility was 22.8 wt.% at 550 ℃based on the regression analysis method. Mg5＋xGd （0〈x〈2） and Mg3Gd precipitates coexisted in all investigated alloys owing to the strong component segregation during solidification. The fraction of Mg5＋xGd （0〈x〈2） was decreased with the increment of annealing temperature and time. In contrast, Mg3Gd precipitate could not be elimi- nated even when being annealed at 550℃. This thermal stable precipitate played a significant role in mechanical properties. Therefore, it is very necessary to consider the effect of Mg3Gd precipitate on properties of Mg-Gd based alloys in future.
Gadolinium （Gd） solubility in magnesium （Mg） matrix and precipitate composition in Mg-Gd binary alloys were investigated. The alloys containing different Gd contents （10 wt.%-35 wt.%） were employed to identify Gd solubility after annealing at different temperatures. It was confirmed that the maximum Gd solubility was 22.8 wt.% at 550 ℃based on the regression analysis method. Mg5＋xGd （0〈x〈2） and Mg3Gd precipitates coexisted in all investigated alloys owing to the strong component segregation during solidification. The fraction of Mg5＋xGd （0〈x〈2） was decreased with the increment of annealing temperature and time. In contrast, Mg3Gd precipitate could not be elimi- nated even when being annealed at 550℃. This thermal stable precipitate played a significant role in mechanical properties. Therefore, it is very necessary to consider the effect of Mg3Gd precipitate on properties of Mg-Gd based alloys in future.
基金
Project supported by National Natural Scientific Foundation of China(51101142,50821001)
Postdoctoral Science Foundation(2012M510766)
