氧含量对钕铁硼镝扩散梯度的影响研究  

Influence of Oxygen on Dysprosium Gradient in Grain Boundary Diffusion Processed NdFeB Magnet

作　　者：程星华 李建[2] 周磊[2] 刘涛[2] 喻晓军[2] 李波[1] Cheng Xinghua;Li Jian;Zhou Lei;Liu Tao;Yu Xiaojun;Li Bo(Central Iron and SteelResearch Institute,Beijing 100081,China;Advanced Technology and Materials Co.,Ltd.,Beijing101318,China)

机构地区：[1]钢铁研究总院,北京100081 [2]安泰科技股份有限公司,北京101318

出　　处：《中国稀土学报》2019年第2期186-192,I0002,共8页Journal of the Chinese Society of Rare Earths

基　　金：安泰科技股份有限公司技术创新项目(2012JA01GGN)资助

摘　　要：主要对不同厚度烧结钕铁硼磁体进行Dy晶界扩散,主要研究了磁体氧含量的高、低对成分及磁性能梯度分布的影响。研究发现:高、低氧磁体方形度均会随着厚度增加而下降,其中前者的下降幅度尤为显著。将磁体沿着厚度方向切片进行分析发现,低氧磁体成分及矫顽力的纵深梯度分布较为均匀。电子探针微观分析结果显示:高氧样品中O, Dy元素均集中富集在团块状的富Nd相之中;而低氧样品中这种团块稀少, Dy分布在其他微细晶界形成连续条纹。低氧磁体为Dy扩散提供了连续的通道,最终能使Dy扩散饱和度及矫顽力饱和度更大于高氧磁体。The NdFeB sintered magnets with different thicknesses were processed by Dy grain boundary diffusion, the main purpose of this work is to investigate the influence of oxygen content on gradient distribution of composition and magnetic performance. It was found that, the squareness decrease happened both in high and low-oxygen magnets, and it was more obvious especially in the former one. The magnets were cut into slices perpendicular to the thickness direction and it was also found that the lateral distributions of composition and coercivity were more homogeneous in low-oxygen magnets. EPMA showed that, most of Dy and O were concentrated in the triple junction Nd-rich phases in high-oxygen magnets, while these junctions were more rarely enabling Dy to form a continuous Dy-rich shell along the narrow grain boundaries in low-oxygen ones. Low-oxygen magnet provided a more continuous channel for Dy diffusion, which made the magnet to own a higher saturation Dy content and coercivity.

关 键 词：烧结钕铁硼 晶界扩散 氧含量 镝含量 梯度分布 

分 类 号：TM273[一般工业技术—材料科学与工程]