Purification of rare-earth metals as the approach to improving properties of hard magnetic Nd2Fe14B-based materials

2nd International Symposium on Fundamental Aspects of Rare-earth Elements Mining and Separation and Modern Materials Engineering

材料科学;物理学

Kolchugina, N.B.^1 ; Burkhanov, G.S.^1 ; Dormidontov, A.G.^1 ; Lukin, A.A.^2 ; Koshkid'Ko, Yu S.^3,4 ; Skotnicová, K.^3 ; Drulis, H.^5 ; Smetana, B.^3

Baikov Institute of Metallurgy and Materials Science, Russian Academy of Science, Leninskii pr. 49, Moscow

119991, Russia^1

JSC Spetsmagnit, Dmitrovskoe sh. 58, Moscow

127238, Russia^2

Vysoka Skola Banska - Technical University of Ostrava, 17 Listopadu 15/2172, Ostrava-Poruba

70833, Czech Republic^3

International Laboratory for High Magnetic Fields and Low Temperatures, Polish Academy of Sciences, Gajowicka 95, Wroclaw

53-421, Poland^4

Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okolna 2, Wroclaw

50-422, Poland^5

关键词: Dysprosium hydrides;    High coercivity;    Hydride additions;    Nd2Fe14B;    Rare earth metals;    Sintered magnets;    Vacuum distillation;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/112/1/012009/pdf
DOI  :  10.1088/1757-899X/112/1/012009

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

Purification of rare-earth metals, namely, Nd, Pr, Tb, Dy used in manufacturing Nd2Fe14B-based magnets was realized. The metals were purified by vacuum distillation/sublimation. Conditions of the process were optimized and the structure of distilled metals was studied. Distilled terbium and dysprosium were used to prepare hydrides TbH2 and DyH2. Peculiarities of the decomposition of terbium and dysprosium hydrides were studied with the view of the use of the compounds as efficient additions, which allow the high- coercivity state of sintered magnets to be formed. Terbium hydride additions (to 4 wt %) favor the marked increase in the magnetization coercive force without excessive attenuation of the remanence (jHc= 1940 kA/m, (BHmax) = 292 kJ/m3). Dysprosium hydride additions increase the stability of high-coercivity state (jHc= 1310 kA/m, (BHmax) = 322 kJ/m3at 2 wt% DyH2).