LiF-[CaF2/YbF3]-Yb2O3熔盐及Yb-Ni合金密度特性研究OA北大核心CSTPCD

The density of LiF-[CaF2/YbF3]-Yb2O3 molten salt system is an important parameter for preparing rare earth Yb alloy by electrolysis.In this paper,Archimedes method was used to measure and analyze the density of LiF-[CaF2/YbF3]-Yb2O3 system and its changing rule in the temperature range of 1 173-1 573 K.Meanwhile,mathematical models were used to estimate the density of Yb-Ni alloy and analyze its separation characteristic between molten salt and alloy during electrolysis.The results showed that the density of the system(LiF-CaF2)eut and(LiF-YbF3)eut system decreased linearly with higher temperature,and the molar volume increased linearly with rising temperature.Moreover,the excess volume of(LiF-YbF3)eut system decreased linearly with the temperature.In the range of Yb2O3 ratio from 0 to 4wt%with the temperature ranging between 1 173 and 1 573 K,the density of(LiF-CaF2)eut-Yb2O3 and(LiF-YbF3)eut-Yb2O3 molten salt systems decreased linearly as the temperature rised.When the temperature was constant,(LiF-CaF2)eut-Yb2O3 system increased linearly in the range of 0≤x(Yb2O3)≤2.5%,while(LiF-YbF3)eut-Yb2O3 system increased linearly in the range of 0≤x(Yb2O3)≤3.5%.The density of Yb-Ni alloy was higher than that of LiF-[CaF2/YbF3]-Yb2O3 molten salt system so that it was easier to be separated by electrolysis.