Quantitative analysis of pinning-hardened intrinsic coercivity of Sm (CoFeCuZr)z (z=7.0-7.8) high-temperature permanent magnets

被引：13

作者：

Liu, Bingjie ^{[1
]}

Wang, Hui ^{[1
]}

Yu, Qijia ^{[1
]}

Xu, Hao ^{[1
]}

Zhang, Tianli ^{[1
]}

Liu, Jinghua ^{[1
]}

Jiang, Chengbao ^{[1
]}

机构：

[1] Beihang Univ, Sch Mat Sci & Engn, Key Lab Aerosp Mat & Performance, Minist Educ, Beijing 100191, Peoples R China

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 2021年 / 872卷

基金：

中国国家自然科学基金;

关键词：

SmCo; Permanent magnets; Coercivity mechanism; Intrinsic magnetism; MICROMAGNETIC ANALYSIS; SINTERED MAGNETS; MICROSTRUCTURE; DEPENDENCE; REMANENCE; COBALT; CU;

D O I：

10.1016/j.jallcom.2021.159622

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

SmCo-based permanent magnets possessing high Curie temperature and outstanding magnetocrystalline anisotropy are of great scientific and technological value on high temperature applications. It is widely accepted the coercivity mechanism as well as its temperature dependence is closely related to the microstructure and microchemistry. However, direct domain wall pinning observation with Lorentz microscopy is extremely difficult to explore the strength of domain wall pinning under high temperature and strong magnetic field. The quantitatively understanding of coercivity mechanism such as micromagnetic simulations cannot be carried out without the intrinsic magnetism of 1:5H and 2:17R inside the cellular microstructure of SmCo sintered magnets. Up to nowadays, there are no methods to directly measure the intrinsic magnetism of nanometer scale 1:5H and 2:17R, which retards the exploring of coercivity mechanism especially at high temperature. Herein, we prepared Sm(CoCuFeZr)(z) high-temperature permanent magnets with the ratio z values ranging from 7.0 to 7.8 and measured the microchemistry of 1:5H and 2:17R phases with transmission electron microscopy. Then single-phase solid solution samples with the same composition as 1:5H and 2:17R phases were prepared and the high temperature magnetic properties are measured directly. The coercivity mechanism can be well explained based on the difference of domain wall energy density qualitatively, including the abnormal temperature dependence of coercivity. More importantly, the quantitatively calculated coercivity according to the pinning-hardened coercivity theory with the obtained intrinsic parameters were found to agree well with the experiment results. Our work on the intrinsic magnetism of 1:5H and 2:17R phases at varying temperatures may offer important guidance for compositions design of the magnets with higher performance. (C) 2021 Elsevier B.V. All rights reserved.

引用

页数：7

共 43 条

[1] Sm2(Co,Fe,Cu,Zr)17 magnets for use at temperature ≥400 °C [J].