Abstract In order to investigate the heavy rare earth (HRE) diffusion and the coercivity reinforcement mechanism of Ce based RE2Fe14B magnets, the high Ce content magnet with CeFe2 grain boundary phase was fabricated, and then followed by Tb grain boundary diffusion (GBD) process. The RE2Fe14B magnetic grains were surrounded by CeFe2 phase in the magnet. Being different from the single shell structure of GBD processed Nd-Fe-B sintered magnets, a dual-shell structure with the Tb-rich inner shell of (Tb,Ce)2Fe14B and the Tb-lean outer shell of (Ce,Tb)2Fe14B is formed around the grain core in the high Ce content RE2Fe14B magnet after GBD processed at 940 °C for 10 hours. Coercivity of the high Ce content magnets with CeFe2 grain boundary phase can be reinforced by the dual shell core structure effectively. Microstructure and formation mechanism of the dual-shell core structure were investigated and proposed. The relationship between the coercivity and the dual-shell core structure was discussed.

中文翻译：

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具有 CeFe2 相的晶界扩散高 Ce 含量磁体中的双壳核结构

摘要 为了研究Ce基RE2Fe14B磁体的重稀土（HRE）扩散和矫顽力增强机制，制备了具有CeFe2晶界相的高Ce含量磁体，然后进行Tb晶界扩散（GBD）工艺。RE2Fe14B 磁性颗粒被磁铁中的 CeFe2 相包围。与GBD加工的Nd-Fe-B烧结磁体的单壳结构不同，具有(Tb,Ce)2Fe14B富Tb内壳和(Ce,Tb)贫Tb外壳的双壳结构2Fe14B在高Ce含量RE2Fe14B磁体中，经过GBD在940°C下处理10小时后，在晶核周围形成。双壳核结构可以有效地增强具有CeFe2 晶界相的高Ce 含量磁体的矫顽力。研究并提出了双壳核结构的微观结构和形成机制。讨论了矫顽力与双壳核结构之间的关系。