Tungsten substituted BaFe
12
O
19
single crystal growth
and characterization
D.A. Vinnik
a, *
, D.A. Zherebtsov
a
, L.S. Mashkovtseva
a
, S. Nemrava
b
, A.K. Yakushechkina
c
,
A.S. Semisalova
c
, S.A. Gudkova
a, g
, A.N. Anikeev
a
, N.S. Perov
c, e
, L.I. Isaenko
d, f
, R. Niewa
b
a
South Ural State University, Lenin's Prospect 76, Chelyabinsk 454080, Russia
b
University of Stuttgart, Pfaffenwaldring 55, Stuttgart 70569, Germany
c
Lomonosov Moscow State University, Leninskie Gory 1-2, Moscow 119991, Russia
d
Institute of Geology and Mineralogy, Siberian Branch, Russian Academy of Sciences, Ac. Koptyuga ave., Novosibirsk 630090, Russia
e
Baltic Federal University, Nevskogo Street14 A, Kaliningrad 236041, Russia
f
Novosibirsk State University, Pirogova Street 2, 630090 Novosibirsk, Russia
g
Moscow Institute of Physics and Technology (State University), Institutskiy per. 9, Dolgoprudny 141700, Moscow Region, Russia
highlights graphical abstract
Growth of large W-substituted crys-
tals BaFe
12x
W
x
O
19
.
W-content controllable by flux
composition.
W substitution influence on the unit
cell parameters.
Magnetic characterization depending
on W-content.
article info
Article history:
Received 10 December 2014
Received in revised form
5 February 2015
Accepted 15 February 2015
Available online 19 February 2015
Keywords:
Magnetic materials
Crystal growth
Crystal structure
Magnetic properties
abstract
Tungsten-substituted barium hexaferrite single crystals were grown by flux method at 900e1260
C.
Crystals of BaFe
12ex
W
x
O
19
with x up to 0.06 were obtained. The W content in the crystals can be
controlled via the W content in the flux. Upon increase of the tungsten concentration the cell parameters
and magnetic properties change. W doping results in an increase of coercive force from 331 to 489 Oe,
which makes these materials prospective for permanent magnets. The substitution results in a small
reduction of the Curie temperature from 455 to 453.1
C and in a decreasing saturation magnetization at
room temperature from 71 to 64 emu/g for powder samples.
© 2015 Elsevier B.V. All rights reserved.
1. Introduction
Barium hexaferrite is one of the most important commercial
hard magnetic materials, representing the class of hexagonal M-
type ferrites [1e5]. The large magnetocrystalline anisotropy, high
saturation magnetization and coercivity, high electrical resistivity
* Corresponding author.
E-mail addresses: denisvinnik@gmail.com (D.A. Vinnik), zherebtsov_da@yahoo.
com (D.A. Zherebtsov), l2787@yandex.ru (L.S. Mashkovtseva), nemrava@iac.uni-
stuttgart.de (S. Nemrava), yako.msu@yandex.ru (A.K. Yakushechkina),
semisalova@magn.ru (A.S. Semisalova), svetlanagudkova@yandex.ru
(S.A. Gudkova), anikeev-ml@mail.ru (A.N. Anikeev), perov@magn.ru (N.S. Perov),
lisa@igm.nsc.ru (L.I. Isaenko), iacniewa@iac.uni-stuttgart.de (R. Niewa).
Contents lists available at ScienceDirect
Materials Chemistry and Physics
journal homepage: www.elsevier.com/locate/matchemphys
http://dx.doi.org/10.1016/j.matchemphys.2015.02.005
0254-0584/© 2015 Elsevier B.V. All rights reserved.
Materials Chemistry and Physics 155 (2015) 99e103