Experimental investigation and thermodynamic assessment of La-Y-Ni ternary system in Ni-rich corner  

作　　者：Sheng-Xiang Wu Li Wang Hui-Ping Yuan Qun Luo Qian Li Kuo-Chih Chou 

机构地区：[1]State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization,Baotou Research Institute of Rare Earths,Baotou,014030,China [2]State Key Laboratory of Advanced Special Steels,Shanghai Key Laboratory of Advanced Ferrometallurgy,School of Materials Science and Engineering,Shanghai University,Shanghai,200444,China [3]GRIMAT Engineering Institute Co.,Ltd.,Beijing,101407,China [4]National Engineering Research Center for Magnesium Alloys,Chongqing University,Chongqing,400044,China

出　　处：《Rare Metals》2023年第4期1316-1331,共16页稀有金属（英文版）

基　　金：financially supported by the National Key R&D Program of China(No.2021YFB3502200);National Natural Science Foundation of China(No.51734002);Science and Technology Committee of Shanghai(Nos.19010500400 and 19DZ2252900);Shanghai Rising-Star Program(No.21QA1403200)。

摘　　要：La-Y-Ni alloys exhibit high discharge capacity due to the formation of AB_(3-3.8)-type(A=La,Y;B=Ni)intermetallic compounds.However,the stable composition and temperature range for this type of phase are rarely reported,which restrains the development of La-Y-Ni hydrogen storage alloys with stable structure and high capacity.This paper focuses on the phase equilibria of the La-Y-Ni ternary system in Ni-rich corner.The phase constitution,microstructure,and equilibrated composition were experimentally determined at 1273 and 1148 K using X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy-dispersive spectroscopy(EDS).The solubilities of La and Y in the binary compounds were measured.Two ternary compounds,3R-LaY_(2)Ni_(9)with the structure of PuNi3 type and La_(0.5)Y_(0.5)Ni_(5)with the structure of CaCu5 type,existed at both temperatures.Based on the experimental data,the thermodynamic description of LaY-Ni system was assessed by Calculation of Phase Diagram method.The calculated isothermal sections agree with the experimental data.The thermodynamic database is helpful for the design of La-Y-Ni hydrogen storage alloys.

关 键 词：La-Y-Ni system Phase equilibria Calculation of Phase Diagram(CALPHAD) Isothermal section Phase transformation 

分 类 号：TG139.7[一般工业技术—材料科学与工程]