摘要
采用物理气相沉积工艺在商用N35级烧结钕铁硼磁体表面沉积0.3 wt%的镝金属,并在910℃的热处理过程中施加频率为50 Hz的弱磁场,研究了弱交变磁场辅助晶界扩散对磁体矫顽力的影响。磁性能测试显示,相比于原始磁体,常规扩散和0.3 T弱交变磁场辅助扩散的矫顽力分别增加了3.28 kOe和5.02 kOe。基于扫描电镜图像,使用ImageJ软件分析了扩散磁体中的粒径分布,发现与原始磁体的平均粒径相比,磁场辅助扩散过程中晶粒没有进一步长大,但常规扩散磁体的平均粒径却增长了约0.5μm。能量色散光谱仪线扫描结果显示,在距磁体镀镝表面400~1500μm范围内,磁场辅助扩散磁体的镝含量明显高于常规扩散。结果表明,弱交变磁场辅助晶界扩散能够有效抑制晶粒长大和增加镝元素沿晶界扩散的深度;磁体矫顽力的提升应归因于这些效应的叠加。实验结果为进一步优化烧结钕铁硼磁体晶界扩散工艺提供了新方案。
The influence of weak alternating magnetic field-assisted grain boundary diffusion on the coercivity of commercial N35 grade sintered Nd-Fe-B magnets was studied by depositing O.3 wt% Dy metal on the magnet surface using physical vapor deposition and applying a weak magnetic field with a frequency of 50 Hz during the heat treatment process at 910℃.Magnetic property tests show that compared to the original magnet,both conventional diffusion and 0.3 T weak alternating magnetic field-assisted diffusion increase the coercivity by 3.28 kOe and 5.02 kOe,respectively.Based on BSE-SEM images,the grain size distribution in the diffused magnets is analyzed using ImageJ software.It is found that the grain size does not further increase during the magnetic fieldassisted diffusion process,while the average grain size of the magnet diffuses by conventional diffusion increases by approximately 0.5μm.EDS line scan results show that within the range of 400μm to 1500μm from the Dy-coated surface of the magnet,the Dy content of the magnet diffused with magnetic field assistance is significantly higher than that of the conventionally diffused magnet.These results indicate that weak alternating magnetic field-assisted grain boundary diffusion can effectively suppress grain growth and increase the diffusion depth of Dy along the grain boundaries.The improvement in coercivity is attributed to the combined effects of these mechanisms.The experimental results provide a new approach for further optimizing the grain boundary diffusion process of sintered Nd-Fe-B magnets.
作者
吕燕武
吕军
刘海晨
房漠楠
黄二愿
LU Yanwu;LU Jun;LIU Haichen;FANG Monan;HUANG Eryuan(School of Materials Science and Engineering,Inner Mongolia University of Technology,Hohhot 010051,China;Inner Mongolia Key Laboratory of Thin Film and Coatings Technology,Hohhot 010051,China;College of Science,Inner Mongolia University of Technology,Hohhot 010051,China;Baotou Prosper Permanent Magnet Co.,Ltd.,Baotou 014030,China)
出处
《内蒙古大学学报（自然科学版）》
CAS
2024年第3期273-280,共8页
Journal of Inner Mongolia University：Natural Science Edition
基金
内蒙古自然科学基金项目(2022LHMS03014)
内蒙古研究生直属高校基本科研业务费项目(JY20220069,ZTY2023046)
“科技兴蒙”行动重点专项(XM2021BT08)。
关键词
钕铁硼
晶界扩散
磁场辅助
矫顽力
NdFeB
grain boundary diffusion
magnetic field-assistance
coercivity
作者简介
吕燕武(1998-),男,河南中牟人,2021级硕士研究生。E-mail:ngerqiu@163.com;通信作者:吕军(1973-),男,内蒙古乌拉特前旗人,教授,博士。主要从事基于物理因素改善烧结铁硼磁性能研究与理论生物物理研究。E-mail:lujun@imut.edu.cn。
