Effect of post-sinter annealing on the coercivity and microstructure of Nd-Fe-B permanent magnets

被引：284

作者：

Li, W. F. ^{[1
]}

Ohkubo, T. ^{[1
]}

Hono, K. ^{[1
]}

机构：

[1] Natl Inst Mat Sci, Tsukuba, Ibaraki 3050047, Japan

来源：

ACTA MATERIALIA | 2009年 / 57卷 / 05期

关键词：

Nd-Fe-B permanent magnets; Sintered magnets; Grain boundary; Atom probe; ADDITIONS; COPPER;

D O I：

10.1016/j.actamat.2008.11.019

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

To understand the mechanism of the increase in coercivity caused by post-sinter annealing of Nd-Fe-B-based magnets, we have investigated the microstructures of commercial sintered magnets by high-resolution scanning electron microscopy, transmission electron microscopy and atom probe tomography. Continuous thin layers of a Nd-rich amorphous phase were found along the grain boundaries in the post-sinter annealed sample, the chemical composition of which was determined to be Nd30Fe45Cu24.1N0.9. A fine Cu-enriched shell was also confirmed in the Nd-rich phase grain, suggesting the Nd2Fe14B grains are completely enveloped by the Cu- and Nd-enriched layers. Furthermore, a lamellar microstructure of the Cu-enriched phase was confirmed in some Nd-rich phase grains. The mechanism of the coercivity increase caused by post-sinter annealing is discussed based on these characterization results. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

引用

页码：1337 / 1346

页数：10

共 16 条

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