Angular dependence and thermal stability of coercivity of Nd-rich Ga-doped Nd-Fe-B sintered magnet

被引：36

作者：

Li, J. ^{[1
]}

Tang, Xin ^{[1
]}

Sepehri-Amin, H. ^{[1
]}

Sasaki, T. T. ^{[1
]}

Ohkubo, T. ^{[1
]}

Hono, K. ^{[1
]}

机构：

[1] Natl Inst Mat Sci, Elements Strategy Initiat Ctr Magnet Mat, Tsukuba, Ibaraki 3050047, Japan

来源：

ACTA MATERIALIA | 2020年 / 187卷

关键词：

Ga-doped sintered magnet; Micromagnetic simulation; Angular dependence of coercivity; Thermal stability of coercivity; GRAIN-BOUNDARY; MAGNETIZATION REVERSAL; NUCLEATION; FORCE;

D O I：

10.1016/j.actamat.2020.01.035

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We studied the angular dependence and thermal stability of coercivity of Nd-rich Ga-doped Nd-Fe-B sintered magnets. Experimentally measured angular dependence of coercivity for the as-sintered magnet agrees well with the micromagnetic simulation results for exchange-coupled polycrystalline model that assumes the magnetization reversal is dominated by the domain wall depinning at the grain boundaries. On the other hand, the measured angular dependence of coercivity of the post-sinter annealed sample with an enhanced coercivity deviates from fully exchange-decoupled model in spite of previous experimental results on inter grain exchange decoupling. Based on micromagnetic simulations and Kronmuller equation, it is suggested that the entire elimination of magnetic exchange coupling between Nd2Fe14B grains can further improve the coercivity and its thermal stability of the 5 mu m-grain-sized Dy-free magnet. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页码：66 / 72

页数：7

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