Effective anisotropy and coercivity in nanocrystalline single-phase NdFeB permanent magnetic material  

作　　者：韩广兵 高汝伟 冯维存 刘汉强 王标 张鹏 陈伟 李卫 郭永权 

机构地区：School of Physics and Microelectronics, Shandong University, Jinan 250100, China[1] Central Iron and Steel Research Institute, Beijing 100081, China[2]

出　　处：《Science China(Physics,Mechanics & Astronomy)》2003年第4期398-404,共7页中国科学：物理学、力学、天文学（英文版）

基　　金：the National'863'Project of China(Grant No.2002AA324050);the National Natural Science Foundation of China(Grant Nos.9971026);the Nature Science Foundation of Shandong Province(Grant No.Y2000F10)

摘　　要：The effect of exchange-coupling interaction on the effective anisotropy and its varying tendency in nanocrystalline single-phase NdFeB permanent magnetic material have been investigated. The results show that the exchange-coupling interaction between grains makes the effective anisotropy of material, Keff, decrease with the reduction of grain size. The variation of Keff is basically the same as that of coercivity. The decrease in effective anisotropy is the main reason of the reduction of coercivity for nanocrystalline single-phase NdFeB permanent magnetic material. In order to get high anisotropy and coercivity in nanocrystalline single-phase NdFeB permanent material, the grain size should be larger than 35 nm.The effect of exchange-coupling interaction on the effective anisotropy and its varying tendency in nanocrystalline single-phase NdFeB permanent magnetic material have been investigated. The results show that the exchange-coupling interaction between grains makes the effective anisotropy of material,K eff, decrease with the reduction of grain size. The variation ofK eff is basically the same as that of coercivity. The decrease in effective anisotropy is the main reason of the reduction of coercivity for nanocrystalline single-phase NdFeB permanent magnetic material. In order to get high anisotropy and coercivity in nanocrystalline single-phase NdFeB permanent material, the grain size should be larger than 35 nm.

关 键 词：NANOCRYSTALLINE SINGLE-PHASE PERMANENT magnetic material  EXCHANGE-COUPLING interaction  effective anisotropy  COERCIVITY 

分 类 号：O482.54[一般工业技术—材料科学与工程]