Dy Thermal Diffusion Process of NdFeB Magnets and Its Coercive Force Improvement Mechanism

被引：0

作者：

Liu F.-G. ^{[1
,2
]}

Zhao D. ^{[1
,2
]}

Xiang L. ^{[1
,2
]}

Pei W.-L. ^{[1
,2
]}

机构：

[1] School of Materials Science & Engineering, Northeastern University, Shenyang

[2] Key Laboratory for Anisotropy and Texture of Materials of Ministry of Education, Northeastern University, Shenyang

来源：

Dongbei Daxue Xuebao/Journal of Northeastern University | 2022年 / 43卷 / 04期

关键词：

Coercive force; Dy diffusion process; Grain boundary diffusion; Grain size; NdFeB magnets;

D O I：

10.12068/j.issn.1005-3026.2022.04.009

中图分类号：

学科分类号：

摘要：

The commercial 35M magnet prepared from recycled materials was used as the research object, and a self-made new DyF3 coating was used to conduct thermal diffusion treatment on the magnets. The results show that the new coating has the characteristics of quick-drying, good adhesion and uniform coating, which effectively improves the stability of thermal diffusion process. The magnet subjected to thermal diffusion treatment at 920 ℃×10 h, has a good performance on the magnetic properties, where the coercive force of the magnet reaches 1 710.2 kA/m with an increase of 37.9%. Microstructure analysis reveals the diffusion process of Dy element and the mechanism of coercive force improvement of the magnet. It is found that Dy element diffuses along the grain boundary and a Dy-rich shell of(Nd, Dy)2Fe14B with a higher anisotropy field can be formed around the grains of main phase, which makes the Nd-rich phase of the grain boundary more continuous and clear, resulting in a substantial increase in the coercive force of the magnet. © 2022, Editorial Department of Journal of Northeastern University. All right reserved.

引用

页码：517 / 523

页数：6

共 19 条

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