scholarly journals Magneto-Dielectric Behaviour of M-Type Hexaferrite/Polymer Nanocomposites

Materials ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 2551 ◽  
Author(s):  
A. Sanida ◽  
S. G. Stavropoulos ◽  
Th. Speliotis ◽  
G. C. Psarras
Keyword(s):  
Magnetic Properties ◽  
Polymer Matrix ◽  
Magnetic Measurements ◽  
Magnetic Transition ◽  
Interfacial Polarization ◽  
Electrical Energy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Broadband Dielectric Spectroscopy ◽  
Ferromagnetic Nature

In the present study two sets of nanocomposites consisting of an epoxy resin and BaFe12O19 or SrFe12O19 nanoparticles were successfully developed and characterized morphologically and structurally via scanning electron microscopy and X-ray diffraction spectra. The dielectric response of the nanocomposites was investigated by means of broadband dielectric spectroscopy and their magnetic properties were derived from magnetization tests. Experimental data imply that the incorporation of the ceramic nanoparticles enhances significantly the dielectric properties of the examined systems and their ability to store electrical energy. Dielectric spectra of all systems revealed the presence of three distinct relaxation mechanisms, which are attributed both to the polymer matrix and the nanoinclusions: Interfacial polarization, glass to rubber transition of the polymer matrix and the re-orientation of small polar side groups of the polymer chain. The magnetic measurements confirmed the ferromagnetic nature of the nanocomposites. The induced magnetic properties increase with the inclusion of hexaferrite nanoparticles. The nanocomposites with SrFe12O19 nanoparticles exhibit higher values of coercive field, magnetization, magnetic saturation and remanence magnetization. A magnetic transition was detected in the ZFC/FC curves in the case of the BaFe12O19/epoxy nanocomposites.

Influence of Alloying Additions on Enhancement of Soft Magnetic Properties Effect and Crystallization in FeXSiB (X=Cu, V, Co, Zr, Nb) Amorphous Alloys

2007 ◽  
Vol 130 ◽  
pp. 171-174 ◽  
Author(s):  
Z. Stokłosa ◽  
G. Badura ◽  
P. Kwapuliński ◽  
Józef Rasek ◽  
G. Haneczok ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Amorphous Alloys ◽  
Crystallization Process ◽  
Annealing Temperature ◽  
Magnetic Measurements ◽  
X Ray Diffraction ◽  
Soft Magnetic ◽  
X Ray ◽  
Second Stage ◽  
Transmission Electron

The crystallization and optimization of magnetic properties effects in FeXSiB (X=Cu, V, Co, Zr, Nb) amorphous alloys were studied by applying X-ray diffraction methods, high resolution transmission electron microscopy (HRTEM), resistometric and magnetic measurements. The temperatures of the first and the second stage of crystallization, the 1h optimization annealing temperature and the Curie temperature were determined for different amorphous alloys. Activation energies of crystallization process were obtained by applying the Kissinger method. The influence of alloy additions on optimization effect and crystallization processes was carefully examined.

scholarly journals Structural and Magnetic Properties of FePd Thin Film Synthesized by Electrodeposition Method

Materials ◽  
2020 ◽  
Vol 13 (6) ◽  
pp. 1454
Author(s):  
Gabriele Barrera ◽  
Federico Scaglione ◽  
Matteo Cialone ◽  
Federica Celegato ◽  
Marco Coïsson ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Magnetic Properties ◽  
Deposition Time ◽  
Magnetic Measurements ◽  
X Ray Diffraction ◽  
X Ray ◽  
Fundamental Properties ◽  
Magnetic Features ◽  
Application Fields

Bimetallic nanomaterials in the form of thin film constituted by magnetic and noble elements show promising properties in different application fields such as catalysts and magnetic driven applications. In order to tailor the chemical and physical properties of these alloys to meet the applications requirements, it is of great importance scientific interest to study the interplay between properties and morphology, surface properties, microstructure, spatial confinement and magnetic features. In this manuscript, FePd thin films are prepared by electrodeposition which is a versatile and widely used technique. Compositional, morphological, surface and magnetic properties are described as a function of deposition time (i.e., film thickness). Chemical etching in hydrochloric acid was used to enhance the surface roughness and help decoupling crystalline grains with direct consequences on to the magnetic properties. X-ray diffraction, SEM/AFM images, contact angle and magnetic measurements have been carried out with the aim of providing a comprehensive characterisation of the fundamental properties of these bimetallic thin films.

Structural and magnetic properties of DyCo4−xFexGa compounds

2010 ◽  
Vol 25 (S1) ◽  
pp. S31-S35
Author(s):  
W. H. Zhang ◽  
J. Q. Li ◽  
Y. J. Yu ◽  
F. S. Liu ◽  
W. Q. Ao ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Magnetic Measurements ◽  
Uniaxial Anisotropy ◽  
Solubility Limit ◽  
Spin Reorientation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Spin Reorientation Transition ◽  
Structural And Magnetic Properties

The structural and magnetic properties of the DyCo4−xFexGa compounds with x=0, 0.5, 1, and 1.5 have been investigated by X-ray diffraction and magnetic measurements. Powder X-ray diffraction analysis reveals that each of the DyCo4−xFexGa compounds has a hexagonal CaCu5-type structure (space group P6/mmm). The Fe solubility limit in DyCo4−xFexGa is x<1.5. The higher the value of x, the larger the unit-cell parameters a, c, V, and the 3d-sublattice moment but the smaller the 3d uniaxial anisotropy. Magnetic measurements show that the Curie temperature of DyCo4−xFexGa increases from 498 K for x=0 to 530 K for x=1.5, the compensation temperature Tcomp decreases from 286 K for x=0 to 238 K for x=1.5, and the spin-reorientation transition temperature increases from 403 K for x=0 to 530 K for x=0.5. No spin-reorientation transition was found in the samples with x=1.0 and 1.5. The saturation magnetization of DyCo4−xFexGa measured at 173 K increases but the magnetization measured at 300 K decreases with increasing Fe content x.

Structural, dielectric and magnetic properties of Pr-, Tb- and Dy-doped (Bi0.95RE0.05)(Fe0.95Mn0.05)O3 ceramics synthesized by solid-state reaction method

2013 ◽  
Vol 03 (04) ◽  
pp. 1350033 ◽  
Author(s):  
Radheshyam Rai ◽  
Shweta Thakur ◽  
M. A. Valente ◽  
Andrei L. Kholkin
Keyword(s):  
Magnetic Properties ◽  
Solid State ◽  
Solid State Reaction ◽  
Magnetic Measurements ◽  
Ferroelectric Properties ◽  
Solid State Reaction Method ◽  
X Ray Diffraction ◽  
Solid State Reaction Technique ◽  
X Ray ◽  
Ceramic Samples

The multiferroic ( Bi 0.95 RE 0.05)( Fe 0.95 Mn 0.05) O 3 (where RE = Pr , Tb and Dy ) has been synthesized using solid-state reaction technique. Effects of Pr , Tb and Dy substitution on the structure, electrical and ferroelectric properties of ( Bi 0.95 RE 0.05)( Fe 0.95 Mn 0.05) O 3 samples have been studied by performing X-ray diffraction, dielectric measurements and magnetic measurements. The crystal structure of the ceramic samples have a monoclinic phase. The vibrating sample magnetometer (VSM) measurement shows a significant change in the magnetic properties of Pr -, Tb - and Dy -doped ( Bi 0.95 RE 0.05)( Fe 0.95 Mn 0.05) O 3. It is seen that coercive field (Hc) and remanent magnetization (Mr) increases for Pr but decreases for Dy and Tb .

scholarly journals Influence of the Quenching Rate on the Structure and Magnetic Properties of the Fe-Based Amorphous Alloy

2016 ◽  
Vol 61 (1) ◽  
pp. 439-444 ◽  
Author(s):  
M. Nabiałek
Keyword(s):  
Magnetic Properties ◽  
Amorphous Alloy ◽  
Magnetic Measurements ◽  
Mössbauer Spectrometry ◽  
X Ray Diffraction ◽  
Quenching Rate ◽  
X Ray ◽  
Transmission Electron ◽  
Mossbauer Spectrometry ◽  
Diffraction Patterns

This paper presents the results of investigations into the structure, microstructure and magnetic properties of Fe61Co10Y8W1B20 amorphous alloy. The alloy samples were in two physical forms: (1) plates of approximate thickness 0.5 mm (so-called bulk amorphous alloys) and (2) a ribbon of approximate thickness 35 μm (so-called classic amorphous alloy). The investigations comprised: X-ray diffractometry, Mössbauer spectrometry, transmission electron microscopy, and selected magnetic measurements; all of the investigations were carried out on samples in the as-quenched state. Analysis of the obtained SEM and TEM images, X-ray diffraction patterns, Mössbauer spectrometry results and measurements of the magnetisation in a high magnetic field facilitated collectively the detailed description of the structure of the investigated alloy, which was found to depend on the quenching speed.

Structural, Mechanical and Magnetic Properties of Mechanically Alloyed Fe40Co60 Powders

2011 ◽  
Vol 312-315 ◽  
pp. 743-747 ◽  
Author(s):  
Fadhela Otmane ◽  
S. Bergheul ◽  
M. Zergoug ◽  
M. Azzaz
Keyword(s):  
Grain Size ◽  
Magnetic Properties ◽  
Magnetic Measurements ◽  
Lattice Parameter ◽  
Internal Strain ◽  
Morphological Aspect ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
Mechanically Alloyed ◽  
X Ray

In this work we report on the structural, mechanical and magnetic properties of mechanically alloyed Fe40Co60 powders. Alloying formation, grain size, lattice parameter and internal strain were investigated using X-Ray Diffraction (XRD) measurements. The morphological aspect of the nanostructured powders was analysed by means of the Scanning Electron Microscopy (SEM). Compacted pastilles with circular shape have been under Vickers test of micro Hardness and magnetic measurements of Hysterisis loops. Discussed results according to milling time show that after 60 h milling the grain refinement is about 15.59 nm with internal strain of around 0.5809 %. The micro hardness increases with the decrease of the grain size and the hysterisis loop at 60 h milling is enhanced in term of decreased coercivity.

Magnetic properties of (Sr1.85Ln0.15)FeMoO6 with Ln = Sr, La, Ce, Pr, Nd, Sm and Eu

2011 ◽  
Vol 239-242 ◽  
pp. 3109-3112 ◽  
Author(s):  
Qin Zhang ◽  
Qing Wang ◽  
Zhen Cui Sun ◽  
Ke Yan Wang
Keyword(s):  
Magnetic Properties ◽  
Rare Earth ◽  
Ionic Radius ◽  
Single Phase ◽  
Magnetic Measurements ◽  
Rare Earth Ions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Rare Earth Doped ◽  
The Eu

Rare-earth-doped compounds (Sr1.85Ln0.15)FeMoO6(Ln=Sr, La, Ce, Pr, Nd, Sm and Eu) have been prepared by solid-state reaction. Crystal structure and magnetic properties were investigated by means of X-ray diffraction and magnetic measurements. All the samples are single phase and belong to the I4/m space group. Due to the competing contributions of electron doping and steric effects, the unit-cell volume of the doped compounds changes slightly and does not vary systematically with the ionic radius of the rare-earth ions. The temperature dependence of the magnetization of (Sr1.85Ln0.15)FeMoO6indicates that the Curie temperature of the doped compounds has increased upon doping, except for the Eu-doped compound.

scholarly journals Magnetic properties of a new cobalt hydrogen vanadate with a dumortierite-like structure: Co13.5(OH)6(H0.5VO3.5)2(VO4)6

2019 ◽  
Vol 75 (6) ◽  
pp. 777-782
Author(s):  
Mohammed Hadouchi ◽  
Abderrazzak Assani ◽  
Mohamed Saadi ◽  
Abdelilah Lahmar ◽  
Mimoun El Marssi ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Magnetic Properties ◽  
Single Crystal ◽  
Magnetic Measurements ◽  
Crystal Form ◽  
X Ray Diffraction ◽  
One Dimensional ◽  
X Ray ◽  
Pyramidal Groups ◽  
Scanning Electron

The magnetic properties of a novel cobalt-based hydrogen vanadate, Co13.5(OH)6(H0.5VO3.5)2(VO4)6, are reported. This new magnetic material was synthesized in single-crystal form using a conventional hydrothermal method. Its crystal structure was determined from single-crystal X-ray diffraction data and was also characterized by scanning electron microscopy. Its crystal framework has a dumortierite-like structure consisting of large hexagonal and trigonal channels; the large hexagonal channels contain one-dimensional chains of face-sharing CoO6 octahedra linked to the framework by rings of VO4 tetrahedra, while the trigonal channels are occupied by chains of disordered V2O4 pyramidal groups. The magnetic properties of this material were investigated by DC magnetic measurements, which indicate the occurrence of antiferromagnetic interactions.

Structural and magnetic properties of pure and cobalt doped Gallium Nitride nanocrystals

2010 ◽  
Vol 1257 ◽  
Author(s):  
Vottikondala Ganesh ◽  
Suresh Sundaram ◽  
Krishnan Baskar
Keyword(s):  
Magnetic Properties ◽  
Gallium Nitride ◽  
Magnetic Measurements ◽  
Raw Materials ◽  
Ferromagnetic Behavior ◽  
Secondary Phases ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structural And Magnetic Properties ◽  
Co Doped

AbstractIn the present study pure and doped gallium nitride (GaN) nanocrystals were synthesized using gallium trichloride (GaCl3), ethylene diamine tetra acetic acid (EDTA) and cobalt chloride as raw materials at a temperature of 900 °C in ammonia (NH3) atmosphere. The XRD spectrum for pure and cobalt doped GaN nanocrystals shows the formation of single phase wurtzite structure. No impurity phases were observed in the X-ray diffraction pattern for 5% Co doped sample whereas secondary phases were observed when the doping concentration exceeds 5 %. Shift in X-ray diffraction peaks were observed in Co doped samples towards lower angle side compared to pure GaN, it confirms that the Co atoms introduces in to the GaN lattice. Transmission electron microscopy images were taken for pure and Co doped GaN. Hexagonal morphology was observed in pure GaN samples. The average size of the particle was found to be ˜20 nm for pure and Co doped GaN. The magnetic measurements were carried out for the Co (5% & 10%) doped samples both at 10K and 300K. Clear hysteresis loop in the magnetization curve suggest the presence of ferromagnetic behavior in cobalt doped GaN. Temperature dependent magnetization (M-T) measurements were also carried out for doped samples using Super Conducting Quantum Interface Device (SQUID) from 10K to 300K The results have been discussed and correlated to structural and magnetic properties of the materials.

Low temperature magnetic transition and high temperature oxidation in INCONEL alloy 718

1996 ◽  
Vol 11 (5) ◽  
pp. 1133-1136 ◽  
Author(s):  
Mohindar S. Seehra ◽  
V. Suresh Babu
Keyword(s):  
High Temperature ◽  
Magnetic Measurements ◽  
Magnetic Transition ◽  
Aging Treatment ◽  
Nominal Composition ◽  
Alloy 718 ◽  
X Ray Diffraction ◽  
Austenitic Phase ◽  
Temperature Oxidation ◽  
X Ray

X-ray diffraction and temperature dependent (5 K–380 K) magnetic measurements have been carried out in INCONEL 718 superalloy before and after high temperature aging treatments. (INCONEL is a trademark of the INCO family of companies.) The nominal composition of this alloy is Ni (52.5%), Cr (19.0%), Fe (18.5%), Nb (5.1%), Mo (3.0%), Ti (0.9%), Al (0.5%), Cu (0.15%), and C (0.08%), and it yields an x-ray diffraction pattern consisting of a fcc phase with α = 3.5987 (3) Å and an orthorhombic phase associated with δ-Ni3Nb. It is concluded that the fcc pattern is due to both the γ austenitic phase and γ′ Ni3(Al, Ti) phase of alloy 718. The standard annealing and aging treatment carried out in air at temperatures between 621 and 982 °C produces surface oxides (Cr, Fe)2O3 and FeNbO4 (which are easily removed by etching and polishing) and contracts the lattice. Magnetic measurements show a distinct phase transition at Tc = 14 K, which has been attributed to the γ′-Ni3(Al, Ti) phase by the process of elimination and by observing that it has most of the characteristics of the weak itinerant ferromagnet Ni74.5Al25.5. This transition may have some effects on the cryogenic applications of this alloy.

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