软/硬双相纳米永磁体的强磁机制及组织调控  

Strong Magnetic Mechanism and Microstructure Regulation of Soft/Hard Dual-Phase Nano-Permanent Magnets

作　　者：张一昆 王书桓 柳昆 赵定国 宋春燕 Zhang Yikun;Wang Shuhuan;Liu Kun;Zhao Dingguo;Song Chunyan(College of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063210,China;Tangshan Key Laboratory of Special Metallurgy and Material Preparation,North China University of Science and Technology,Tangshan 063210,China)

机构地区：[1]华北理工大学冶金与能源学院,河北唐山063210 [2]华北理工大学唐山市特种冶金及材料制备重点实验室,河北唐山063210

出　　处：《稀有金属》2020年第11期1215-1220,共6页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(51574104);唐山市特种冶金及材料制备基础创新团队项目(171302021)资助。

摘　　要：在单相纳米稀土永磁研究和制备遇到瓶颈的基础上,通过介绍纳米双相稀土永磁材料的优越磁性能,引出纳米双相稀土永磁材料研究的必要性。简述了纳米双相稀土永磁材料晶粒间的交换耦合作用机制及剩磁增强原理,确定了获得最优磁性能时所对应的软/硬磁晶粒尺寸及其体积分数范围,得出当软磁相晶粒尺寸~10 nm,硬磁晶粒尺寸~30 nm,且软磁相体积分数在30%~70%之间时,矫顽力达到最大值。深入分析了矫顽力的形核机制和钉扎机制以及矫顽力过低的原因,指出软/硬磁相晶粒尺寸、体积分数、以及组织缺陷和界面成分及结构对矫顽力的影响,为后续克服矫顽力与剩磁之间此消彼长的关系奠定理论基础,最后对软/硬双相纳米永磁的组织调控方法,提出核壳结构组织在同时提高矫顽力和剩磁方面的优异性,以及大塑性变形法在组织调控方面的优势,最后对纳米双相永磁材料的发展进行了展望。Considering the bottleneck of single-phase nano rare earth permanent magnetic research and preparation,this paper introduced the necessity of research on nano dual-phase rare earth permenant magnetic materials by introducing the superior magnetic properties.The change coupling mechanism and remanence enhancement principle of nano-biphase rare earth permanent magnet materials were briefly described.The corresponding grain size and volume fraction range of soft and hard magnetic phases that intended to obtain magnetic properties were determined.The soft magnetic phase grain size was~10 nm,and that of the hard magnetic grain was about30 nm,and the soft magnetic phase volume fraction should be about 30%~70%when the coercive force reached the maximum value.The nucleation mechanism and pinning mechanism of coercivity and the reasons of low coercivity were analyzed in depth.The grain size and volume fraction of soft and hard magnetic phases,the effects of microstructure defects,interfacial composition and structure on coercivity were pointed.In order to overcome the relationship between coercivity and remanence,the theoretical basis was established.Finally,the microstructure regulation method of soft/hard dual-phase nano-permanent magnets was summarized,and the coreshell structure was proposed to improve coercivity and remanence simultaneously.The advantages of the large plastic deforation method in the microstructure control were stated,and finally the outlook of nano dual-phase permanent magnet materials was given.

关 键 词：纳米双相 永磁材料 晶间交换耦合 矫顽力机制 

分 类 号：TG146.4[一般工业技术—材料科学与工程]