Fine-grained NdFeB magnets prepared by low temperature pre-sintering and subsequent hot pressing

被引：8

作者：

Ju Jin-Yun ^{[1
,2
]}

Tang Xu ^{[1
,2
]}

Chen Ren-Jie ^{[1
,2
]}

Wang Jin-Zhi ^{[3
]}

Yin Wen-Zong ^{[1
,2
]}

Don, Lee ^{[1
,2
]}

Yan A-Ru ^{[1
,2
]}

机构：

[1] Chinese Acad Sci, Ningbo Inst Mat Technol & Engn, Key Lab Magnet Mat & Devices, Ningbo 315201, Zhejiang, Peoples R China

[2] Chinese Acad Sci, Ningbo Inst Mat Technol & Engn, Zhejiang Prov Key Lab Magnet Mat & Applicat Techn, Ningbo 315201, Zhejiang, Peoples R China

[3] Ningbo Univ Technol, Ningbo 315201, Zhejiang, Peoples R China

来源：

CHINESE PHYSICS B | 2015年 / 24卷 / 01期

基金：

中国国家自然科学基金;

关键词：

NdFeB magnets; grain refinement; hot press; pre-sintering; PERMANENT-MAGNETS; COERCIVITY; MICROSTRUCTURE;

D O I：

10.1088/1674-1056/24/1/017504

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Fine-grained Nd10.79Pr2.8Al0.4B7.72Fe78.29 magnets were prepared by low temperature pre-sintering and subsequent hot pressing. The grain size of the magnets is just about 1-3 mu m because the low sintering temperature results in no grain growth. The orientation degree, microstructure, and magnetic properties were studied. Some grains' easy axes deviate from the orientation direction, possibly due to grain rotation during the hot pressing. By subsequent annealing, the magnetic properties were significantly enhanced. Especially, the squareness of the demagnetization curve was improved greatly. The enhancement of coercivity by annealing can be explained by an improvement of both grain boundaries and magnetic isolation, which decouples the exchange interaction between neighboring grains.

引用

页数：5

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