Coercivity enhancement of Ce-containing hot-deformed magnets by grain boundary diffusion of DyF_(3)  

作　　者：Bin Chen Jinyun Ju Wenzong Yin Xu Tang Renjie Chen Aru Yan Longquan Hou Yeyuan Du 

机构地区：[1]CAS Key Laboratory of Magnetic Materials and Devices,Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences,Ningbo 315201,China [2]University of Chinese Academy of Sciences,Beijing 100049,China [3]School of Environment and Safety Engineering,North University of China,Taiyuan 030051,China

出　　处：《Journal of Rare Earths》2022年第2期289-295,I0004,共8页稀土学报（英文版）

基　　金：Project supported by the Ningbo Science and Technology Major Project(2017B10002,2019B10093);the Zhejiang Province Technology Application Research(LGG19E010001);the National Natural Science Foundation of China(51671207)。

摘　　要：The samples with full density were prepared by hot pressing the the melt-spun powders mixed with DyF_(3)powders of different mass fractions followed by hot-deformation process.The magnetic properties and temperature dependence of coercivity were obtained by BH tracer and VSM,respectively.The microstructure were analyzed by scanning electron microscopy(SEM)and transmission electron microscopy(TEM).The coercivity of Ce-containing hot-deformed magnets is increased from 1.41 to 1.95 T by grain boundary diffusion of 3 wt%DyF_(3),and is further enhanced to 2.05 T after annealing treatment.The thermal stability of coercivity and remanence is improved.The annealing condition in this work crucially plays a role in thickening the grain boundary phase.Microstructure analysis reveals that the continuous and thick grain boundary phase formed after DyF_(3)diffusion can weaken the magnetic coupling between grains,and suppress the platelet shaped grain size and the aspect ratio.The Dycontaining shell structure formed by the partial diffusion of Dy into the main phase can increase the magnetic anisotropy field,which is the main reason for the coercivity improvement.After optimizing the structure by DyF_(3)diffusion,the"dendritic-like"reverse domain is transformed into the"dot scatteredlike"reverse domain.

关 键 词：Ce-containing hot-deformed magnet COERCIVITY Grain boundary phase Dy-containing shell structure Rare earths 

分 类 号：TB34[一般工业技术—材料科学与工程]