热扩渗DyZn合金膜层对烧结钕铁硼磁性能与耐热性能的影响  

Effects of Thermal Diffusing DyZn Alloy Film on Magnetic Properties and Heat Resistance of Sintered NdFeB Magnets

作　　者：李家节 郭诚君 周头军 刘武杰 陈金水 刘仁辉 周慧杰 杨斌 Li Jiajie1,2, Guo Chengjun2, Zhou Toujun2, Liu Wujie2, Chen Jinshui2, Liu Renhui1, Zhou Huijie3, Yang Bin1,2(1. Institute of Engineering and Research, Jiangxi University of Science and Technology, Ganzhou 341000, China） （2. School of Material Science and Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China） （3. Ganzhou Qiandong Rare Earth Group Co., Ltd, Ganzhou 341000, China)

机构地区：[1]江西理工大学工程研究院,江西赣州341000 [2]江西理工大学材料科学与工程学院,江西赣州341000 [3]虔东稀土集团股份有限公司,江西赣州341000

出　　处：《稀有金属材料与工程》2018年第3期995-1000,共6页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51561009);江西省高校科技落地计划项目(KJLD14043);江西省青年科学基金计划项目(20151BAB216005);江西省教育厅研究项目(GJJ14448)

摘　　要：采用直流磁控溅射的方法,在烧结NdFeB磁体表面制备了DyZn薄膜,研究了热扩渗处理磁体前后的磁性能、温度稳定性及微观组织结构变化。结果表明,晶界扩散渗DyZn处理后,磁体在保持剩磁基本不降低的情况下,矫顽力大幅度提升,矫顽力从原来的963.68 kA/m提高到1544.60 kA/m,增幅达63.31%。晶界扩散处理可以改善磁体的温度稳定性,在293~453 K范围内,剩磁温度系数基本不变,而矫顽力温度系数由–0.5533%/K降低为–0.4885%/K。通过对样品微观组织结构观察发现,Dy元素沿着晶界液相扩散,主要富集在晶界相和晶粒外延层处,晶界相结构与成分的优化、及晶界和晶粒之间(Nd,Dy)_2Fe_(14)B过渡层的形成是矫顽力大幅度提升的主要原因。DyZn films on the sintered NdFeB magnet surface were prepared by DC magnetron sputtering. The magnetic properties, temperature stability and microstructure change of the magnets before and after the thermal diffusion treatment were compared. The results show that after DyZn thermal diffusion the coercivity of the magnet is enhanced significantly from 963.68 to 1544.60 kA/m with an increase of 63.31%, and at the same time it keeps the remanence invariable. The magnet temperature stability can be improved by grain boundary diffusion. The temperature coefficient of the remanence keeps constant while that of the coercivity is reduced from –0.5533%/K to –0.4885%/K in the range of 293~453 K. SEM and EPMA with EDS observation indicate that Dy elements diffusing along the grain boundary phase mainly aggregate in the grain boundary phase and the grain epitaxial layer. The optimization of microstructure and composition of the grain boundary phase and the formed（Nd, Dy）_2Fe_（14）B transition layer are the main reasons which upgrade the coercivity dramatically.

关 键 词：共溅射 热扩渗 DyZn合金 烧结钕铁硼 

分 类 号：TM273[一般工业技术—材料科学与工程]