Structural, Mechanical and Magnetic Properties of Mechanically Alloyed Fe40Co60 Powders

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.

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Structural and Magnetic Properties of Nanogranular BaTiO3-CoFe2O4 Thin Films Deposited by Laser Ablation on Si/Pt Substrates

Materials Science Forum ◽

10.4028/www.scientific.net/msf.587-588.303 ◽

2008 ◽

Vol 587-588 ◽

pp. 303-307

Author(s):

J.G. Barbosa ◽

Bernardo G. Almeida ◽

João P. Araújo ◽

João Bessa Sousa ◽

Jorge A. Mendes

Keyword(s):

Thin Films ◽

Grain Size ◽

Magnetic Properties ◽

Laser Ablation ◽

Barium Titanate ◽

Cobalt Ferrite ◽

Magnetic Measurements ◽

X Ray Diffraction ◽

Clear Trend ◽

X Ray

Thin film nanocomposites of cobalt ferrite (CoFe2O4) dispersed in barium titanate (BaTiO3) matrix, have been deposited with different cobalt ferrite concentrations (from 20% to 70% CoFe2O4), as well as pure barium titanate and cobalt ferrite thin films (end members). The films were prepared by pulsed laser ablation on platinum covered Si(001) substrates. The films structure was studied by X-ray diffraction and their surface was examined by scanning electron microscopy (SEM). The magnetic properties were measured in a SQUID magnetometer. The results show that the deposited films are polycrystalline with a slight (111) barium titanate phase orientation and (311) CoFe2O4 phase orientation. The grain sizes measured from the X-ray diffraction peak widths, for both phases, are in the range 40nm to 100nm. However, as the concentration of the cobalt ferrite increases, the grain size of the BaTiO3 phase decreases, from 100nm to 30nm, up to 40% CoFe2O4 concentration beyond which the BaTiO3 grain size has an approximately constant value near 30nm. On the other hand the cobalt ferrite grain size does not show a clear trend with increasing cobalt ferrite concentration, fluctuating in the range 20nm to 30nm. The magnetic measurements show an increase of the magnetic moment from the low concentration region where the magnetic grains are more isolated and their magnetic interaction is small, towards the bulk value at higher CoFe2O4 concentrations. Also, a strong reduction of the magnetization with increasing temperature was observed, due to the corresponding decrease of the magnetocristalline anisotropy of the cobalt ferrite.

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Effect of Heat Treatment on Structural and Magnetic Properties of Li-Ni Ferrite Prepared via Sol-Gel Auto-Combustion Method

10.21203/rs.3.rs-166543/v1 ◽

2021 ◽

Author(s):

Jiali Song ◽

Zhi Wang ◽

Yu Gao

Keyword(s):

Grain Size ◽

Magnetic Properties ◽

Annealing Temperature ◽

Sol Gel ◽

Combustion Method ◽

Lattice Parameter ◽

X Ray Diffraction ◽

X Ray ◽

Auto Combustion ◽

Ft Ir

Abstract Nanocrystalline Li 0.35 Ni 0.3 Fe 2.35 O 4 ferrites were prepared at different annealing temperature by sol-gel auto-combustion method. The effects of the annealing temperature on the structure and magnetic properties of the synthesized Li-Ni ferrites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectra (FT-IR) and Squid-VSM. Rietveld refinement of the X-ray diffraction data confirmed the occurrence of phase transition from α-spinel to β-spinel, from which the ideal cation occupation and lattice parameter can be obtained. The grain size increased significantly with annealing temperature. The variation of saturation magnetization can be well explained in terms of the occupation of ions in tetrahedron and octahedron. The coercivity initially increased and later decreased significantly from 115 to 37 Oe with the increase of annealed temperature which could be attributed the fact that the 600℃-annealed grain size is close to transition size from single to multidomain region.

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Effect of Nitridation Magnetic Properties of Nanocrystalline Fe-Co Alloy Powders

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.1106 ◽

2010 ◽

Vol 654-656 ◽

pp. 1106-1109

Author(s):

Ya Qiong He ◽

Chang Hui Mao ◽

Jian Yang

Keyword(s):

Grain Size ◽

Magnetic Properties ◽

Alloy Powder ◽

High Energy ◽

X Ray Diffraction ◽

Powder Mixtures ◽

X Ray ◽

Transmission Electron ◽

Nitridation Temperature ◽

Microstructure And Magnetic Properties

Nanocrystalline Fe-Co alloy powders, which were prepared by high-energy mechanical milling, were nitrided under the mixing gas of NH3/H2 in the temperature range from 380°C to 510°C. X-ray diffraction (XRD) was used to analyze the grain size and reaction during the processing. The magnetic properties of the nitrided powders were measured by Vibrating Sample Magnetometer (VSM). The results show that with the appearance of Fe4N phase after nitride treatment, and the grain-size of FeCo phase decreases with the increase of nitridation temperature between 380°C to 450°C.The saturation magnetization of nitrided alloy powder treated at 480°C is about 18% higher than that of the initial Fe-Co alloy powder, accompanied by the reduction of the coercivity. Transmission electron microscope (TEM) was used, attempting to further analyze the effect of Fe4N phase on microstructure and magnetic properties of the powder mixtures.

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Structural Evolution in Wet Mechanically Alloyed Co-Fe-(Ta,W)-B Alloys

Metals ◽

10.3390/met11050800 ◽

2021 ◽

Vol 11 (5) ◽

pp. 800

Author(s):

Vladimír Girman ◽

Maksym Lisnichuk ◽

Daria Yudina ◽

Miloš Matvija ◽

Pavol Sovák ◽

...

Keyword(s):

Structural Changes ◽

Magnetic Measurements ◽

Structural Evolution ◽

High Energy ◽

Control Agent ◽

X Ray Diffraction ◽

Mechanically Alloyed ◽

X Ray ◽

Transmission Electron ◽

X Ray Absorption

In the present study, the effect of wet mechanical alloying (MA) on the glass-forming ability (GFA) of Co43Fe20X5.5B31.5 (X = Ta, W) alloys was studied. The structural evolution during MA was investigated using high-energy X-ray diffraction, X-ray absorption spectroscopy, high-resolution transmission electron microscopy and magnetic measurements. Pair distribution function and extended X-ray absorption fine structure spectroscopy were used to characterize local atomic structure at various stages of MA. Besides structural changes, the magnetic properties of both compositions were investigated employing a vibrating sample magnetometer and thermomagnetic measurements. It was shown that using hexane as a process control agent during wet MA resulted in the formation of fully amorphous Co-Fe-Ta-B powder material at a shorter milling time (100 h) as compared to dry MA. It has also been shown that substituting Ta with W effectively suppresses GFA. After 100 h of MA of Co-Fe-W-B mixture, a nanocomposite material consisting of amorphous and nanocrystalline bcc-W phase was synthesized.

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

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.130.171 ◽

2007 ◽

Vol 130 ◽

pp. 171-174 ◽

Cited By ~ 3

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.

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TEM Study of FePt and FePt:C/FePt Composite Double-Layered Thin Films

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.275-277.1952 ◽

2013 ◽

Vol 275-277 ◽

pp. 1952-1955

Author(s):

Ling Fang Jin ◽

Xing Zhong Li

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Grain Size ◽

Magnetic Properties ◽

Composite Layer ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron

New functional nanocomposite FePt:C thin films with FePt underlayers were synthesized by noneptaxial growth. The effect of the FePt layer on the ordering, orientation and magnetic properties of the composite layer has been investigated by adjusting FePt underlayer thickness from 2 nm to 14 nm. Transmission electron microscopy (TEM), together with x-ray diffraction (XRD), has been used to check the growth of the double-layered films and to study the microstructure, including the grain size, shape, orientation and distribution. XRD scans reveal that the orientation of the films was dependent on FePt underlayer thickness. In this paper, the TEM studies of both single-layered nonepitaxially grown FePt and FePt:C composite L10 phase and double-layered deposition FePt:C/FePt are presented.

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

Materials ◽

10.3390/ma13061454 ◽

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.

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Grain Size Dependent Magnetic Properties of Nanocrystalline Sm [BE]Co [BD][BJ]/Cu

MRS Proceedings ◽

10.1557/proc-703-v3.16 ◽

2001 ◽

Vol 703 ◽

Author(s):

L. Bessais ◽

C. Djéga-Mariadassou ◽

J. Zhang ◽

V. Lalanne ◽

A. Percheron-Guégan

Keyword(s):

Grain Size ◽

Magnetic Properties ◽

Rietveld Method ◽

X Ray Diffraction ◽

X Ray ◽

Size Dependent ◽

Transmission Electron ◽

Average Grain Size ◽

Magnetic Metal ◽

Chemical Distribution

ABSTRACTThe evolution of both micro structural and magnetic properties of the Sm[BE]Co[BD][BJ] Cu powder, is studied as a function of soft co-milling time. The average grain size in the range 20 - 50 nm was determined by transmission electron microscopy coupled with x-ray diffraction using the Rietveld method. The particle shape and chemical distribution were investigated by elemental mapping, using wavelength dispersive x-ray analysis with electron microprobe analysis. The coercivity evolution shows that an optimum value of 6 kOe is obtained after 5 h co-milling. The microstructure analysis indicates that both materials are well mixed in nanometer scale. This technique appears as a potential route to synthesize nanocrystalline Sm[BE]Co[BD][BJ] isolated by non-magnetic metal Cu.

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Structural and magnetic properties of DyCo4−xFexGa compounds

Powder Diffraction ◽

10.1154/1.3478562 ◽

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.

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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

Journal of Advanced Dielectrics ◽

10.1142/s2010135x13500331 ◽

2013 ◽

Vol 03 (04) ◽

pp. 1350033 ◽

Cited By ~ 2

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 .

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