NdFeB磁体的Dy热扩渗过程及其矫顽力提高机制

doi:10.12068/j.issn.1005-3026.2022.04.009

东北大学学报（自然科学版） ›› 2022, Vol. 43 ›› Issue (4): 517-523.DOI: 10.12068/j.issn.1005-3026.2022.04.009

NdFeB磁体的Dy热扩渗过程及其矫顽力提高机制

刘富刚^1,2，赵东^1,2，向令^1,2，裴文利^1,2

(1.东北大学材料科学与工程学院，辽宁沈阳110819; 2.东北大学材料各向异性与织构教育部重点实验室，辽宁沈阳110819)

修回日期:2021-04-01 接受日期:2021-04-01 发布日期:2022-05-18
通讯作者: 刘富刚
作者简介:刘富刚(1997-)，男，甘肃白银人，东北大学硕士研究生；裴文利(1970-)，男，辽宁沈阳人，东北大学教授，博士生导师.
基金资助:
国家自然科学基金资助项目(51871045，52071070); 中央高校基本科研业务费专项资金资助项目(N2017003).

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

LIU Fu-gang^1,2， ZHAO Dong^1,2， XIANG Ling^1,2， PEI Wen-li^1,2

1.School of Materials Science & Engineering， Northeastern University， Shenyang 110819， China; 2.Key Laboratory for Anisotropy and Texture of Materials of Ministry of Education， Northeastern University， Shenyang 110819， China.

Revised:2021-04-01 Accepted:2021-04-01 Published:2022-05-18
Contact: PEI Wen-li
About author:-
Supported by:
-

摘要/Abstract

摘要： 采用回收料制备的商业35M磁体作为研究对象，使用自制新型DyF₃涂料对磁体进行热扩渗处理.研究表明:新型涂料具有速干、附着力好、涂覆均匀的特点，有效改善了热扩渗工艺的稳定性;该磁体经过920℃×10h的热扩渗处理，获得了良好的综合磁性能，磁体矫顽力提高到1710.2kA/m，增幅为37.9%.微观结构分析揭示了Dy元素的扩渗过程和磁体矫顽力提高机理.Dy元素沿晶界扩渗，在主相晶粒周围形成了各向异性场更高(Nd， Dy)₂Fe₁₄B的富Dy壳层，使晶界富Nd相变得更加连续、清晰，导致磁体矫顽力大幅增加.

关键词: NdFeB磁体;晶粒尺寸;晶界扩渗;矫顽力;Dy扩渗过程

Abstract: 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℃×10h， has a good performance on the magnetic properties， where the coercive force of the magnet reaches 1710.2kA/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.

Key words: NdFeB magnets; grain size; grain boundary diffusion; coercive force; Dy diffusion process

中图分类号:

TM273

刘富刚，赵东，向令，裴文利. NdFeB磁体的Dy热扩渗过程及其矫顽力提高机制[J]. 东北大学学报（自然科学版）, 2022, 43(4): 517-523.

LIU Fu-gang， ZHAO Dong， XIANG Ling， PEI Wen-li. Dy Thermal Diffusion Process of NdFeB Magnets and Its Coercive Force Improvement Mechanism[J]. Journal of Northeastern University(Natural Science), 2022, 43(4): 517-523.

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NdFeB磁体的Dy热扩渗过程及其矫顽力提高机制

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

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