高矫顽力烧结钕铁硼磁体重稀土减量研究进展  

Progress of Heavy Rare Earths Reduction in High Coercivity Sintered NdFeB Magnets

作　　者：李成灿 许亿 李国栋 李光[1,3] 高方圆 夏原[1,3] Li Chengcan;Xu Yi;Li Cuodong;Li Guang;Gao Fangyuan;Xia Yuan(Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China;School of Engineering Science,University of Chinese Academy of Sciences,Beijing 100049,China;Center for Materials Science and Optoelectronic Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院力学研究所,北京100190 [2]中国科学院大学工程科学学院,北京100049 [3]中国科学院大学材料科学与光电工程中心,北京100049

出　　处：《中国稀土学报》2024年第4期603-623,I0001,共22页Journal of the Chinese Society of Rare Earths

基　　金：国家重点研发计划项目(2021YFB3500100)资助。

摘　　要：烧结钕铁硼永磁材料具有超高的剩磁与磁能积,但其内禀矫顽力较低,使其在高温环境中的应用受到一定限制。目前通过晶粒细化、晶界掺杂和晶界扩散等技术可以提高钕铁硼磁体的矫顽力以保证其在高温环境中磁性能的稳定性。为降低制造成本,如何减少高矫顽力烧结钕铁硼磁体制造过程中重稀土用量成为目前研究热点。本文总结了内禀矫顽力机制以及矫顽力技术的优缺点,其中晶界扩散技术通过重稀土选择性扩散可在主相晶粒表面形成各向异性场更强的重稀土壳层,同时连续的晶界相分布增强了退磁耦合作用,可在大幅提升磁体的矫顽力的同时实现重稀土减量,并进一步归纳和探讨晶界扩散源制备方法、成分和基体材料对矫顽力提升效果和重稀土减量的影响,同时对高矫顽力烧结钕铁硼磁体重稀土减量的发展趋势进行了展望。Sintered NdFeB permanent magnets have high remanence and magnetic energy product,but their low intrinsic coercivity limits their application in high temperature environment.The coercivity of NdFeB magnets can be improved by grain refinement,grain boundary doping and grain boundary diffusion process(GBDP)to ensure the stability of magnetic properties in high temperature environment.In order to reduce the manufacturing cost,reducing the amount of heavy rare earths(HRE)in the manufacturing process of high coercivity sintered NdFeB magnets has become a hot research topic.In this paper,the intrinsic coercivity mechanism and the advantages and disadvantages of coercivity techniques are summarized.GBDP form a HRE shell with stronger anisotropic field on the surface of the main grain through the selective diffusion of HRE,and the continuous grain boundary phase distribution can enhance the demagnetizing coupling effect,which can achieve the reduction of HRE while greatly increasing the coercivity of magnets.And we further summarize and discuss the preparation method of diffusion source,composition and substrate material on the coercivity improvement effect and HRE reduction.At the same time,the development trend HRE reduction in high coercivity sintered NdFeB magnets is prospected.

关 键 词：稀土 钕铁硼 永磁材料 矫顽力 重稀土 减量 

分 类 号：TM273[一般工业技术—材料科学与工程]