Nd2Fe14B has generated significant interest since its discovery in the 1980s due to its impressive energy density, which makes it a prime candidate for use in permanent magnet applications. Its performance is known to suffer greatly at the high temperatures required for motor applications around 450K. Core/shell nanocomposites provide a potential route to improve material performance by combining the highly anisotropic permanent magnet with a material with high moment and high Curie temperature. We have used an atomistic spin model to investigate the magnetic properties of Nd2Fe14B with α-Fe in a core/shell nanostructure. We find that at typical motor operating temperatures, increasing α-Fe content reduces the coercivity of the system while enhancing the saturation magnetization. The overall effect is that an improvement in BHmax is seen with increasing α-Fe up to an optimal value of 70vol.%. This property of core/shell nanostructures would make them a suitable substitute for pure Nd2Fe14B while simultaneously lowering the raw material cost of the permanent magnet component of high-performance motors.

1.
M.
Sagawa
,
S.
Fujimura
,
H.
Yamamoto
,
Y.
Matsuura
, and
K.
Hiraga
,
IEEE Trans. Magn.
20
,
1584
(
1984
).
2.
D.
Givord
,
H. S.
Li
, and
J. M.
Moreau
,
Solid State Commun.
50
,
497
(
1984
).
3.
N.
Poudyal
and
J.
Ping Liu
,
J. Phys. D Appl. Phys.
46
,
043001
(
2012
).
4.
R.
Skomski
and
J. M.
Coey
,
Phys. Rev. B Condens. Matter
48
,
15812
(
1993
).
5.
E. F.
Kneller
and
R.
Hawig
,
IEEE Trans. Magn.
27
,
3588
(
1991
).
6.
E. E.
Fullerton
,
J. S.
Jiang
, and
S. D.
Bader
,
J. Magn. Magn. Mater.
200
,
392
(
1999
).
7.
R.
Skomski
,
J. Phys. Condens. Matter
15
,
R841
(
2003
).
8.
S.
Bance
,
H.
Oezelt
,
T.
Schrefl
,
M.
Winklhofer
,
G.
Hrkac
,
G.
Zimanyi
,
O.
Gutfleisch
,
R. F. L.
Evans
,
R. W.
Chantrell
,
T.
Shoji
,
M.
Yano
,
N.
Sakuma
,
A.
Kato
, and
A.
Manabe
,
Appl. Phys. Lett.
105
,
192401
(
2014
).
9.
S.
Bance
,
J.
Fischbacher
, and
T.
Schrefl
,
J. Appl. Phys.
117
,
17A733
(
2015
).
10.
A.
López-Ortega
,
M.
Estrader
,
G.
Salazar-Alvarez
,
A. G.
Roca
, and
J.
Nogués
,
Phys. Rep.
553
,
1
32
(
2015
).
11.
R. F. L.
Evans
,
D.
Bate
,
R. W.
Chantrell
,
R.
Yanes
, and
O.
Chubykalo-Fesenko
,
Phys. Rev. B
84
,
092404
(
2011
).
12.
F.
Dorfbauer
,
R.
Evans
,
M.
Kirschner
,
O.
Chubykalo-Fesenko
,
R.
Chantrell
, and
T.
Schrefl
,
J. Magn. Magn. Mater.
316
,
e791
(
2007
).
13.
S. D.
Oberdick
,
A.
Abdelgawad
,
C.
Moya
,
S.
Mesbahi-Vasey
,
D.
Kepaptsoglou
,
V. K.
Lazarov
,
R. F. L.
Evans
,
D.
Meilak
,
E.
Skoropata
,
J.
van Lierop
,
I.
Hunt-Isaak
,
H.
Pan
,
Y.
Ijiri
,
K. L.
Krycka
,
J. A.
Borchers
, and
S. A.
Majetich
,
Sci. Rep.
8
,
3425
(
2018
).
14.
S.
Liu
,
A.
Higgins
,
E.
Shin
,
S.
Bauser
,
C.
Chen
,
D.
Lee
,
Y.
Shen
,
Y.
He
, and
M. Q.
Huang
,
IEEE Trans. Magn.
42
,
2912
(
2006
).
15.
T.
Schrefl
,
J.
Fidler
, and
H.
Kronmüller
,
Phys. Rev. B Condens. Matter
49
,
6100
(
1994
).
16.
J.
Kuma
,
N.
Kitajima
,
Y.
Kanai
, and
H.
Fukunaga
,
J. Appl. Phys.
83
,
6623
(
1998
).
17.
H.
Fukunaga
and
H.
Nakamura
,
IEEE Trans. Magn.
36
,
3285
(
2000
).
18.
H.
Fukunaga
,
R.
Horikawa
,
M.
Nakano
,
T.
Yanai
,
T.
Fukuzaki
, and
K.
Abe
,
IEEE Trans. Magn.
49
,
3240
(
2013
).
19.
T. L.
Gilbert
,
IEEE Trans. Magn.
40
,
3443
3449
(
2004
).
20.
M. O. A.
Ellis
,
R. F. L.
Evans
,
T. A.
Ostler
,
J.
Barker
,
U.
Atxitia
,
O.
Chubykalo-Fesenko
, and
R. W.
Chantrell
,
Low Temp. Phys.
41
,
705
(
2015
).
21.
R. F. L.
Evans
,
W. J.
Fan
,
P.
Chureemart
,
T. A.
Ostler
,
M. O. A.
Ellis
, and
R. W.
Chantrell
,
J. Phys. Condens. Matter
26
,
103202
(
2014
).
22.
J. D.
Alzate-Cardona
,
D.
Sabogal-Suárez
,
R. F. L.
Evans
, and
E.
Restrepo-Parra
,
J. Phys. Condens. Matter
31
,
095802
(
2019
).
23.
R. F. L.
Evans
,
U.
Atxitia
, and
R. W.
Chantrell
,
Phys. Rev. B Condens. Matter
91
,
144425
(
2015
).
24.
R. F. L.
Evans
,
A.
Naden
,
S.
Westmoreland
,
R.
Cuadrado
,
M.
Probert
,
T.
Shoji
,
M.
Yano
,
A.
Manabe
,
G.
Hrkac
,
T.
Schrefl
,
D.
Givord
, and
R. W.
Chantrell
Atomistic simulation of temperature dependent properties of Nd2Fe14B
” (unpublished) (
2020
).
25.
Q.
Gong
,
M.
Yi
,
R. F. L.
Evans
,
B.-X.
Xu
, and
O.
Gutfleisch
,
Phys. Rev. B
99
,
214409
(
2019
).
26.
J.
Herbst
and
J.
Croat
,
J. Magn. Magn. Mater.
100
,
57
(
1991
).
27.
F.
Cardarelli
,
Materials Handbook: A Concise Desktop Reference
(
Springer Science & Business Media
,
2008
).
28.
W. J.
Fan
,
R. F. L.
Evans
,
Y.
Hancock
, and
R. W.
Chantrell
,
J. Appl. Phys.
109
,
07B752
(
2011
).
29.
D. J.
Griffiths
and
R.
College
,
Introduction to Electrodynamics
(
Prentice Hall
,
Upper Saddle River, NJ
,
1999
), Vol. 3.
30.
C.
Skelland
,
T.
Ostler
,
S. C.
Westmoreland
,
R. F. L.
Evans
,
R. W.
Chantrell
,
M.
Yano
,
T.
Shoji
,
A.
Manabe
,
A.
Kato
,
M.
Ito
,
M.
Winklhofer
,
G.
Zimanyi
,
J.
Fischbacher
,
T.
Schrefl
, and
G.
Hrkac
,
IEEE. Trans. Magn.
54
,
2103405
(
2018
).
You do not currently have access to this content.