scholarly journals Mагнитные и диэлектрические свойства мультиферроиков (1-x)BiFeO-=SUB=-3-=/SUB=--xYMnO-=SUB=-3-=/SUB=-

Author(s):  
В.И. Михайлов ◽  
В.Т. Довгий ◽  
А.И. Линник ◽  
З.Ф. Кравченко ◽  
В.И. Каменев ◽  
...  

AbstractMagnetic hysteresis loops obtained in the fields from 0 to ±2.5 kOe and dielectric permittivity ε (at 1 kHz, 1 MHz, and 8.3 GHz) of (1 – x )BiFeO_3– x YMnO_3 composite multiferroics (0 ≤ x ≤ 0.5) were studied. Ceramic samples of solid solutions were made by the nitrate process. Compositions (1 – x )BiFeO_3– x YMnO_3 with 0.1 ≤ x ≤ 0.5 were found to be soft ferromagnetic materials sensitive to weak magnetic fields. Coercive field H _ c is about 20–32 Oe for these samples. The maximal magnetization was observed in the sample having x = 0.35. For the samples with 0 ≤ x ≤ 0.4 at T = 300 K, the permittivity was ε ~ 17.6–248.6 at the frequency of 1 kHz, 7.8–63.2 at 1 MHz, and 4 ± 0.3 at 8.3 GHz.

2013 ◽  
Vol 58 (4) ◽  
pp. 1361-1364 ◽  
Author(s):  
P. Niemiec ◽  
R. Skulski ◽  
D. Bochenek ◽  
P. Wawrzała

Abstract We present the results of obtaining and investigating ceramic samples of solid solution (1-x)(PbZr0.53Ti0.47O3)- x(PbFe0.5Ta0.5O3) [i.e. (1-x)PZT-xPFT] with x =0.25, 0.35 and 0.45 obtained using conventional ceramic technology. These materials belong to class of materials known as multiferroics. Solid solutions PZT-PFT are the lowest-loss room-temperature multiferroics known, and as a result there are very interesting for magnetoelectric devices. Paper presents the results of termogravimetric investigations, EDS, XRD and main dielectric measurements. It has been stated that with increasing content of PFT decreases the mean diameter of grains and more wide distribution of grain diameters is observed. For x =0.25 sharp phase transition from ferroelectric phase to paraelectric one is observed and high values of dielectric permittivity. Composition PZT-PFT with x =0.45 has the lowest values of dielectric permittivity, and the transition is more diffused. The increase of x leads also to the shift of the temperature of maximum of dielectric permittivity towards lower temperatures. Samples with x =0.25 and x =0.35 exhibit very low values of dielectric losses up to about 100°C. Dielectric losses for samples with x =0.45 are higher. For obtained PZT-PFT samples we have investigated P-E hysteresis loops at room temperature for frequency 1 Hz. For composition x =0.25 it after application the field about 2.5 kV/mm polarization is equal approximately 28 μC/cm2, while for x =0.35, and x =0.45 after application the field about 2.0 kV/mm the polarizations are equal about 25 μC/cm2 and 20 μC/cm2 respectively. Very low values of losses and high values of polarization lead to the conclusion that interesting material PZT-PFT for applications should be composition with x =0.25.


2011 ◽  
Vol 56 (4) ◽  
pp. 1051-1056 ◽  
Author(s):  
R. Skulski ◽  
D. Bochenek ◽  
P. Wawrzała

Technology, Physical Properties and Phase Transitions in PMN-PT-PS CeramicsSolid solution of (1-y)[(1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3]-yPbSnO3(PMN-PT-PS) investigated in this paper is based on (1-x)PMN-xPT (PMN-PT) where, with increasingx, the transition from relaxor to ferroelectric properties is observed depending on composition. PMN-PT ceramics with 0.25<x<0.4 has been obtained using sol-gel method and next mixed together with PS ceramics obtained from oxides. Final sintering of ceramic samples was pressureless. We present the results of microstructure and XRD investigations, dielectric permittivity and hysteresis loops measurements vs. temperature.


1988 ◽  
Vol 49 (C8) ◽  
pp. C8-1907-C8-1908 ◽  
Author(s):  
B. Alessandro ◽  
G. Bertotti ◽  
A. Montorsi

2019 ◽  
Author(s):  
Valentina Guccini ◽  
Sugam Kumar ◽  
Yulia Trushkina ◽  
Gergely Nagy ◽  
Christina Schütz ◽  
...  

The magnetic alignment of cellulose nanocrystals (CNC) and lepidocrocite nanorods (LpN), pristine and in hybrid suspensions has been investigated using contrast-matched small-angle neutron scattering (SANS) under in situ magnetic fields (0 – 6.8 T) and polarized optical microscopy. The pristine CNC (diamagnetic) and pristine LpN (paramagnetic) align perpendicular and parallel to the direction of field, respectively. The alignment of both the nanoparticles in their hybrid suspensions depends on the relative amount of the two components (CNC and LpN) and strength of the applied magnetic field. In the presence of 10 wt% LpN and fields < 1.0 T, the CNC align parallel to the field. In the hybrid containing lower amount of LpN (1 wt%), the ordering of CNC is partially frustrated in all range of magnetic field. At the same time, the LpN shows both perpendicular and parallel orientation, in the presence of CNC. This study highlights that the natural perpendicular ordering of CNC can be switched to parallel by weak magnetic fields and the incorporation of paramagnetic nanoparticle as LpN, as well it gives a method to influence the orientation of LpN.<br>


Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3455
Author(s):  
Tomasz Chady ◽  
Ryszard Łukaszuk

This paper discusses the experimental examination of anisotropic steel-made samples subjected to a static stress load. A nondestructive testing (NDT) measurement system with a transducer, which enables observation of local hysteresis loops and detection of samples’ inhomogeneity, is proposed. Local hysteresis loops are measured on two perpendicular axes, including one parallel to the rolling direction of the samples. The results confirm that the selected features of the local hysteresis loops provide important information about the conditions of ferromagnetic materials. Furthermore, it is shown that the selected parameters of the statistical analysis of the achieved measurements are beneficial for evaluating stress and fatigue changes induced in the material.


RSC Advances ◽  
2021 ◽  
Vol 11 (28) ◽  
pp. 17051-17057
Author(s):  
Anna Eichler-Volf ◽  
Yara Alsaadawi ◽  
Fernando Vazquez Luna ◽  
Qaiser Ali Khan ◽  
Simon Stierle ◽  
...  

PS/CoPd Janus particles respond very sensitively to application of low external magnetic fields. Owing to the magnetic properties, the PS/CoPd particles may be used, for example, to sense the presence of weak magnetic fields as micro-magnetometers.


2014 ◽  
Vol 78 (11) ◽  
pp. 1169-1173 ◽  
Author(s):  
N. A. Yudanov ◽  
A. A. Rudyonok ◽  
L. V. Panina ◽  
A. T. Morchenko ◽  
A. V. Kolesnikov ◽  
...  

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