scholarly journals Influence of starting powder milling on magnetic properties of Mn-Zn ferrite

2017 ◽  
Vol 11 (2) ◽  
pp. 160-169 ◽  
Author(s):  
Miodrag Milutinov ◽  
Maria Nikolic ◽  
Snezana Lukovic ◽  
Nelu Blaz ◽  
Nebojsa Labus ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Empirical Equation ◽  
Structural Parameters ◽  
Core Loss ◽  
Complex Permeability ◽  
Frequency Range ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Core ◽  
Zn Ferrite

In this paper, the influence of additional sieving and milling of starting industrial Mn-Zn powders on magnetic properties was investigated. The starting powder was milled for 60 minutes, followed by sieving through 325 and 400 meshes. The starting and milled powders were used to fabricate toroid shaped samples sintered at 1200?C for 2 hours. Structural parameters of the fabricated samples were analysed by X-ray diffraction and scanning electron microscopy. Complex permeability, core loss density, and hysteresis were measured using the modified watt-meter method. The complex permeability and hysteresis loop were modelled with a new model proposed in the paper. The core loss density was modelled with the Steinmetz empirical equation. The experimental results and calculations show the significance of the additional milling and sieving process on magnetic properties of Mn-Zn ferrite in the frequency range 0.1-10MHz. These processes increase the relative permeability about 3 times and decrease the core loss 4 times by milling of the starting powder.

Investigations on Cu2+-substituted Ni–Zn ferrite nanoparticles

2016 ◽  
Vol 30 (32n33) ◽  
pp. 1650347
Author(s):  
Amarjeet ◽  
Vinod Kumar
Keyword(s):  
Spinel Phase ◽  
Thermo Gravimetric Analysis ◽  
Peak Position ◽  
Precipitation Method ◽  
Gravimetric Analysis ◽  
Frequency Range ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
X Ray ◽  
Zn Ferrite

[Formula: see text] ([Formula: see text] = 0.1, 0.3 and 0.5) nanoparticles were prepared by chemical co-precipitation method. The developed nanoparticles were characterized for structural properties by powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) techniques. Peak position in the X-ray diffraction pattern confirmed the single spinel phase of the developed particles. Infrared (IR) spectroscopy in mid-IR range showed the presence of characteristic absorption bands corresponding to octahedral and tetrahedral bonds in the spinel structure of prepared samples. Thermo-gravimetric analysis (TGA) measurements showed a considerable weight loss in the developed samples above 700[Formula: see text]C. Frequency dependence of the electrical properties of the developed material pellets was studied in the frequency range of 1 kHz–5 MHz. Temperature dependence of the dielectric constant of [Formula: see text] was studied at different temperatures, i.e. at 425, 450 and 475 K, in the frequency range of 1 kHz–5 MHz. It was found that the electrical conductivity decreases with increasing Cu[Formula: see text] ion content while it increases with the increase in temperature.

Controlled Synthesis of Core-Shell Structure SiO2 /NaGdF4:Eu3+ Magnetic and Optical Bifunctional Composite

2014 ◽  
Vol 936 ◽  
pp. 359-363
Author(s):  
Yan Li Wu ◽  
Min Liao ◽  
Hai Xin Ding ◽  
Ru Chun Yang ◽  
Dan Dan Xiong ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Shell Structure ◽  
Photo Luminescence ◽  
Core Shell ◽  
Controlled Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Core ◽  
Core Shell Structure ◽  
Shell Composite

The SiO2/NaGdF4:Eu3+ core/shell composite was prepared by a template-mediated method, making monodispersed SiO2 as core and NaGdF4:Eu colloids as shell, the morphology and the core-shell structure of the resulting particles were analyzed by SEM,X-ray diffraction, and the photo-luminescence and magnetic properties of the microspheres were investigated too. The results shows the composite have great potential to be used as homogeneous magnetic/optical bifunctional material.

scholarly journals Dependence of the magnetic properties of Co/Pd multilayered films on the structural parameters estimated accurately by x‐ray diffraction

1992 ◽  
Vol 72 (10) ◽  
pp. 4986-4988 ◽  
Author(s):  
S. K. Kim ◽  
J. S. Kang ◽  
J. I. Jeong ◽  
J. H. Hong ◽  
Y. M. Koo ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Structural Parameters ◽  
X Ray Diffraction ◽  
Multilayered Films ◽  
X Ray

Proficient Ni-Zn-Cr Ferrites: Synthesis and Characterization

2012 ◽  
Vol 510-511 ◽  
pp. 343-347
Author(s):  
S. Nasir ◽  
M.A. Malik ◽  
G. Asghar ◽  
G.H. Tariq ◽  
M. Akram ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Single Phase ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zn Ferrite ◽  
Phase Spinel ◽  
Scherrer Formula ◽  
Xrd Patterns ◽  
Cr Doping

Ni-Zn ferrite nanoparticles with Cr doping, having the general formula Ni0.5Zn0.5CrxFe2-xO4(x = 0.1, 0.3, 0.5) were prepared by simplified sol-gel method and sintered at 750±5°C. The structural and magnetic properties of the samples sintered at 750±5°C were studied. From X-ray diffraction (XRD) patterns, it was confirmed that the samples have single phase spinel structure. The crystallite size was calculated from the most intense peak (3 1 1) using the Debye Scherrer formula and was found to be in the range of 29-34 nm. The scanning electron microscope images showed that the particle size of the samples were in the range 60-120nm. Quantum design PPMS model 6700 was used to study magnetic properties of these samples. The effect of Cr doping on the magnetic properties was explained on the basis of cations distribution in the crystal structure.

scholarly journals Structural, magnetic properties and microwave absorbing behavior of iron based carbon nanocomposites

2016 ◽  
Vol 12 (1) ◽  
Author(s):  
Mashadi Sunandar
Keyword(s):  
Magnetic Properties ◽  
Mechanical Milling ◽  
Room Temperature ◽  
High Energy ◽  
Frequency Range ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Absorbing Materials ◽  
Milling Method ◽  
Microwave Absorbing

Nanocomposite of α-Fe/C was successfully synthesized by mechanical milling method. Analytical-grade of α-Fe and graphite powders with a purity of greater than 99% were mixed. The mixture was milled for 50 hours at room temperature using High Energy Milling (HEM). The refinement results of X-ray diffraction pattern shows that the α-Fe/C nanocomposite consists of 20 wt% Fe and 80 wt% C. The mechanical milling resulted in α-Fe/C powders with mean particle size ~900 nm. The image reveals the morphology of particle and the particles that exist is aggregates of fine grains. The magnetic properties of the particle α-Fe/C nanocomposite showed low coercivity and high remanent magnetization. The α-Fe/C nanocomposite has certain microwave absorber properties in the frequency range of 9 – 15 GHz, with the maximum reflection loss reaches -10 dB at 12 GHz and the absorption range under −4 dB is from 11.2 to 15.5 GHz with 2 mm thickness. The study concluded that the α-Fe/C nanocomposite shows good candidate materials for microwave absorbing materials applications. 

scholarly journals Structural and dielectric studies of Mg2+ substituted Ni–Zn ferrite

2015 ◽  
Vol 33 (4) ◽  
pp. 806-815 ◽  
Author(s):  
B.B.V.S. Vara Prasad ◽  
B. Rajesh Babu ◽  
M. Siva Ram Prasad
Keyword(s):  
Structural Properties ◽  
Cation Distribution ◽  
Structural Parameters ◽  
Site Occupancy ◽  
Dielectric Constants ◽  
Magnesium Concentration ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zn Ferrite ◽  
Intensity Calculations

AbstractPolycrystalline ferrites having the chemical formula Ni0.65−xZn0.35MgxFe2O4 (0 ⩽ x ⩽ 0.2) were prepared by solid state reaction route in steps of x = 0.04. The effect of incorporation of diamagnetic divalent magnesium at expense of nickel on the structural properties of these ferrites has been studied. The proposed cation distribution was derived from theoretical X-ray diffraction intensity calculations. These intensity calculations were done by varying the concentration of magnesium ions over two sites in the lattice. For a certain amount of magnesium concentration, the calculated and observed X-ray diffraction intensities were found to be in good agreement. Site occupancy of divalent diamagnetic magnesium was established from this cation distribution. The octahedral environment facilitates magnesium to enter the B-site at about 95 % and the remaining 5 % occupy tetrahedral sites (A-sites). The movements of cations between tetrahedral and octahedral sites as a result of magnesium substitution were discussed in the view of structural parameters, such as tetrahedral and octahedral bond lengths, cation-cation and cation-anion distances, bond angles and hopping lengths, which were calculated using experimental lattice constants and oxygen parameters. All structural parameters showed slight deviations from ideal values. Among all magnesium substituted samples, the ones with x = 0.12 exhibited insignificant variation in view of structural properties. Dielectric measurements were conducted at a standard frequency of 1 kHz. Large values of the recorded dielectric constants displayed typical characteristics of bulk ferrites. Both dielectric constant and loss values showed mixed variations, attributed to the loss of zinc ions during the sintering process.

Evaluation of the Morphology and Magnetic Properties of Cr3+- Doped Ni-Zn Ferrites

2008 ◽  
Vol 591-593 ◽  
pp. 120-124
Author(s):  
Valmir José da Silva ◽  
P.T.A. Santos ◽  
Lucianna Gama ◽  
Ruth Herta Goldsmith Aliaga Kiminami ◽  
Daniel R. Cornejo ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Average Crystallite Size ◽  
Sintered Sample ◽  
X Ray Diffraction ◽  
Inverse Spinel ◽  
Nanosized Powders ◽  
X Ray ◽  
Zn Ferrite ◽  
Dry Pressing

This work involved a morphological, microstructural and magnetic characterization of nanosized powders and sintered samples of Ni-Zn ferrite doped with chromium. The effect of substituting Fe3+ for Cr3+ on the final characteristics of the powders and sintered samples was investigated. The Ni-Zn ferrite powders were prepared by combustion reaction using nitrates and urea as fuel, based on the concepts of propellant chemistry. The samples were uniaxially compacted by dry pressing (385 MPa) and sintered at 1200oC/2h, using a heating rate of 5°C/min. The Ni-Zn powders and compacted samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and the measures of their magnetic properties. The results revealed the formation of the cubic crystalline phase of the inverse spinel of Ni-Zn-Cr ferrite. The average crystallite size was 21 nm and 57 nm while the saturation magnetization was 47.0 and 73.1 emu/g for the powder and the sintered sample, respectively.

Structural and Magnetic Properties of Ni0.5Zn0.5Fe2O4 Synthesized through the Sol-Gel Method

2014 ◽  
Vol 664 ◽  
pp. 75-79
Author(s):  
Beh Hoe Guan ◽  
Muhammad Hanif Zahari ◽  
Lee Kean Chuan
Keyword(s):  
Magnetic Properties ◽  
Calcination Temperature ◽  
Sol Gel ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Calcination Temperatures ◽  
Zn Ferrite

This study investigates the influence of calcination temperatures on the magnetic properties of Ni0.5Zn0.5Fe2O4(Ni-Zn) ferrites.Ni-Zn ferrite with the chemical formula Ni0.5Zn0.5Fe2O4was prepared from their respective nitrate salts through the sol-gel method. The resulting ferrites were characterized using X-ray diffraction (XRD), field emission scanning electron microscope (FESEM) and vibrating sample magnetometer (VSM). Single phased Ni0.5Zn0.5Fe2O4 was obtained at all calcination temperatures.FESEM Micrographs reveals an increase in the grain size with the increase of the calcination temperature. Consequently, the magnetic saturation of the samples were found to increase with each increase in the calcination temperature where the highest value obtained is 70.58 emu/g for the samples calcined at 1000°C.

scholarly journals Microstructure and Complex Permeability Spectra of Polycrystalline Cu-Zn Ferrites

2012 ◽  
Vol 4 (3) ◽  
pp. 551-560 ◽  
Author(s):  
Shahida Akhter ◽  
D. P. Paul ◽  
M. A. Hakim ◽  
S. Akhter ◽  
D. K. Saha ◽  
...  
Keyword(s):  
Single Phase ◽  
Sintering Temperature ◽  
Lattice Parameter ◽  
Initial Permeability ◽  
Complex Permeability ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zn Concentration ◽  
Zn Ferrite ◽  
Zn Content

Cu-Zn ferrites of composition Cu1-xZnxFe2O4 were prepared by double sintering ceramic technique at 9500C and 10500C for 3 hours and 2 hours, respectively. Structural and magnetic properties of the Cu-Zn ferrites were investigated by using X-ray diffraction, microstructure study and complex permeability behaviour. X-ray analysis indicated the formation of single-phase cubic spinel structure for all samples. The lattice parameter was found to increase with increasing Zn content obeying Vegard’s law. The X-ray and bulk densities of the Cu-Zn ferrite significantly decreased whereas porosity increased with increasing Zn concentration. Micrographs exhibited decrease in grain size with increasing concentrations. The real part ?’of initial permeability remained constant up to certain lower range of frequency after which it decreased to lower value of permeability. ?’ increased with increasing Zn contents up to x = 0.5, after that it decreased with higher Zn content but  was also found to increase with sintering temperature. The possible reasons responsible for change in structural, microstructural and complex permeability with increasing of non-magnetic Zn2+ ion are ascertained.© 2012 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved.doi: http://dx.doi.org/10.3329/jsr.v4i3.10798 J. Sci. Res. 4 (3), 551-560 (2012)

scholarly journals Effects of Additives and Sintering Time on the Microstructure of Ni-Zn Ferrite and Its Electrical and Magnetic Properties

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Abdollah Hajalilou ◽  
Mansor Hashim ◽  
Halimah Mohamed Kamari
Keyword(s):  
Magnetic Properties ◽  
Saturation Magnetization ◽  
Grain Growth ◽  
Spinel Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrical And Magnetic Properties ◽  
Sintering Time ◽  
Zn Ferrite ◽  
The Relationship

This work aims to investigate the relationship between the microstructure of Ni-Zn ferrite and its electrical and magnetic properties in the presence and absence of as small amounts as 0.12% of 0.4CaO + 0.8SiO2over different sintering times. The X-ray diffraction pattern showed a single spinel phase formation in all the samples. The results indicate that grain growth occurred by increasing sintering time from 15 to 270 min in the two types of samples prepared in this study although it was greatly impeded by the additive oxides. Moreover, the oxides increase the resistivity of the ferrite and decrease its zinc loss. Magnetic properties such as induction magnetization (BS) and saturation magnetization (MS) decreased in the presence of the additives while its coercivity (HC) increased. Finally, the density of the samples was observed to increase with increasing sintering time in both types of the samples but with a higher value in the samples with no additives.

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