The role of local anisotropy profiles at grain boundaries on the coercivity of Nd2Fe14B magnets

被引：108

作者：

Hrkac, Gino ^{[1
]}

Woodcock, Thomas G. ^{[3
]}

Freeman, Colin L. ^{[1
]}

Goncharov, Alexander ^{[1
]}

Dean, Julian ^{[1
]}

Schrefl, Thomas ^{[1
,2
]}

Gutfleisch, Oliver ^{[3
]}

机构：

[1] Univ Sheffield, Dept Mat Engn, Sheffield S1 3JD, S Yorkshire, England

[2] St Polten Univ Appl Sci, A-3100 St Polten, Austria

[3] IFW Dresden, Inst Metall Mat, D-01171 Dresden, Germany

来源：

APPLIED PHYSICS LETTERS | 2010年 / 97卷 / 23期

关键词：

ND-RICH PHASE; PERMANENT-MAGNETS; SINTERED MAGNETS; B MAGNETS; SIMULATION; CRYSTAL; GULP; TEM;

D O I：

10.1063/1.3519906

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

We present numerical evidence from atomistic calculations that the coercivity of high-performance NdFeB-sintered-magnets (<20% of the theoretical Stoner-Wolfarth-limit) can be explained by a distorted region of Nd2Fe14B at grain boundaries, which has a reduced local magnetic anisotropy. We show that depending on the boundary composition of fcc-NdO and hcp-Nd2O3, the thickness of this region of reduced anisotropy varies between 0.4 for fcc and 1.6 nm for the hcp phase. For NdO, the distortions are mostly confined in the fcc-NdO-phase but equally distributes in both the hcp-Nd2O3 and Nd2Fe14B. The experimentally measured coercivity of 1.25 T can be understood when taking this distortion and magnetostatic effects into account. (C) 2010 American Institute of Physics. [doi:10.1063/1.3519906]

引用

页数：3

共 29 条

[1] MAGNETOSTRICTION IN HIGH PULSED MAGNETIC-FIELDS ON A SINGLE-CRYSTAL OF ND2FE14B [J].