Effects of REFe2 on microstructure and magnetic properties of Nd-Ce-Fe-B sintered magnets

被引：180

作者：

Zhang, Yujing ^{[1
]}

Ma, Tianyu ^{[1
]}

Jin, Jiaying ^{[1
]}

Li, Jiangtao ^{[1
]}

Wu, Chen ^{[1
]}

Shen, Baogen ^{[2
]}

Yan, Mi ^{[1
]}

机构：

[1] Zhejiang Univ, Sch Mat Sci & Engn, Key Lab Novel Mat Informat Technol Zhejiang Prov, State Key Lab Silicon Mat, Hangzhou 310027, Zhejiang, Peoples R China

[2] Chinese Acad Sci, Inst Phys, State Key Lab Magnetism, Beijing 100190, Peoples R China

来源：

ACTA MATERIALIA | 2017年 / 128卷

基金：

中国国家自然科学基金;

关键词：

Nd-Fe-B; Highly abundant rare earth; Microstructure; Magnetic properties; GRAIN-BOUNDARY PHASE; PERMANENT-MAGNETS; COERCIVITY ENHANCEMENT; RARE-EARTH; CO; CU; SUBSTITUTION; ALLOY; DY;

D O I：

10.1016/j.actamat.2017.02.002

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Ce substitution level in Nd-Fe-B magnets has been significantly increased via the binary main phase (BMP) approach, i.e. sintering the mixture of Ce-free and Ce-containing RE2Fe14B (RE, rare earth) powders. REFe2 phase that forms in the high Ce-containing Nd-Ce-Fe-B magnets has been considered to be harmful to magnetic performance due to its soft magnetism. In this work, we found that REFe2 phase with lower melting point than the 2:14:1 phase plays positive role on optimizing the microstructure and retaining magnetic performance of the Nd-Ce-Fe-B BMP magnets. The wettability of 2:14:1 phase can be improved by sintering above the melting point of REFe2 phase, which promotes densification of the magnet and the formation of continuous and smooth grain boundary (GB) phases. This contributes to the weakened short-range exchange coupling between adjacent grains, hence ensures superior magnetic performance of BMP magnets to the single main phase (SMP) ones with the same average composition. As a result, magnetic properties of B-r = 12.4 kG, H-cj = 9.0 kOe and (BH)(max) = 36.7 MGOe can be obtained even when 45 wt % Ce substitutes for Nd in the BMP magnets. (C) 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页码：22 / 30

页数：9

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