Influence of microstructure and magnetizing mechanisms on magnetic complex permeability (imaginary part) of a Cu-doped Ni–Zn polycrystalline ferrite

The effect of Co-substitution on the complex permeability of LiZn ferrite was studied. The polycrystalline ferrite samples with a composition of ((Li0.5Fe0.5)0.8Zn0.2)1-xCoxFe2.05O4, where x varies from 0 to 0.08, were prepared by solid-reaction method. The sintered samples were annealed at 490oC for 96 h to produce perminvar effect. The complex permeability was measured in the frequency range from 1 MHz to 2 GHz. The Co-substitution can enhance the real part of complex permeability (μ’). The maximum μ’ appears when x=0.02. The Co-substituted LiZn samples, especially for x=0.02 and 0.04, present resonance-type magnetic spectra obviously. The μ’ of the sample for x=0.02 increases because the damping of domain wall movement decreases after the annealing treatment. The resonance character of the annealed sample becomes even more remarkable due to its domain wall stabilization.

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Structural and Microwave Properties of Copper Ferrite Nanoparticles Prepared by Sol-Gel Synthesis

Journal of Metastable and Nanocrystalline Materials ◽

10.4028/www.scientific.net/jmnm.23.141 ◽

2005 ◽

Vol 23 ◽

pp. 141-144 ◽

Cited By ~ 3

Author(s):

Thresiamma George ◽

Sunny Joseph ◽

Suresh Mathew

Keyword(s):

Imaginary Part ◽

Perturbation Technique ◽

Sol Gel ◽

Chelating Agent ◽

Ferrite Nanoparticles ◽

Microwave Cavity ◽

Complex Permeability ◽

Copper Ferrite ◽

Dielectric Parameters ◽

Sol Gel Synthesis

Copper ferrite nanoparticles are prepared by sol-gel synthesis using polyacrylic acid (PAA) as chelating agent. The crystal structure and surface morphology are studied by XRD and SEM techniques. Microwave dielectric parameters such as real and imaginary part of complex permittivity and a.c. conductivity are determined in the frequency range 2247 - 2970 MHz by microwave cavity perturbation technique. Microwave magnetic parameters such as the real and imaginary part of complex permeability are also determined.

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Complex Permeability of Ferrites Correlated with their Microstructure

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.2560 ◽

2006 ◽

Vol 45 ◽

pp. 2560-2565 ◽

Cited By ~ 3

Author(s):

Janis Jankovskis

Keyword(s):

Grain Size ◽

Size Distribution ◽

Grain Size Distribution ◽

Initial Permeability ◽

The Other ◽

Complex Permeability ◽

Polycrystalline Ferrite

The totality of spinel and garnet polycrystalline ferrite (PF) samples is divided in two subgroups in process of their complex initial permeability (including the static value) relating to their microstructure (MS). The analysis for the first, including PF of rather perfect MS brings to explicit relations showing the effects of grain size distribution. For the other, the group of typical PF, the observed effects is possible to evaluate basing on the results gained for the first group.

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Preparation and Microwave Absorption Property of Nickel Spinel Ferrite

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.531-532.36 ◽

2012 ◽

Vol 531-532 ◽

pp. 36-39

Author(s):

Yuan Liu ◽

Xiang Xuan Liu ◽

Ze Yang Zhang

Keyword(s):

Citric Acid ◽

Microwave Absorption ◽

Imaginary Part ◽

Combustion Temperature ◽

Structural Characteristics ◽

Spinel Ferrite ◽

Sol Gel ◽

Complex Permeability ◽

Microwave Absorbing ◽

Absorbing Property

NiFe2O4 ferrite was synthesized by sol-gel method. Its structural characteristics, morphology, electromagnetic and microwave absorption properties were analyzed by X-ray diffraction, scanning electron microscope and network analyzer, and analyzed the influence of the combustion temperature and citric acid. The results indicated that the particle size be enlarged with an increased combustion temperature and be diminished first, then increased with the increased of citric acid, and the best ratio of citric acid with metal ions for nCA: nFe: nNi = 4:2:1. Its microwave absorbing property is increased with the increased combustion temperature. Its complex permittivity imaginary part first decreases with temperature increases and then increases, the imaginary part of complex permeability with increasing temperature increases, indicating that the increase of calcination temperature, help to improve the sample microwave absorbing properties.

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Static magnetic, complex dielectric and complex permeability properties of aluminum substituted hexagonal barium ferrites based on doping concentration

Journal of the Ceramic Society of Japan ◽

10.2109/jcersj2.21037 ◽

2021 ◽

Vol 129 (9) ◽

pp. 566-573

Author(s):

Xuehai ZHOU ◽

Ke ZHOU ◽

Tianchi ZHANG ◽

Lining FAN ◽

Hongbo ZHANG ◽

...

Keyword(s):

Doping Concentration ◽

Complex Permeability ◽

Barium Ferrites ◽

Magnetic Complex

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The Use of Kramers-Kronig Relations for Verification of Quality of Ferrite Magnetic Spectra

Electrical Control and Communication Engineering ◽

10.1515/ecce-2015-0009 ◽

2015 ◽

Vol 9 (1) ◽

pp. 30-35

Author(s):

Nikolajs Ponomarenko ◽

Tatjana Solovjova ◽

Juris Grizans

Keyword(s):

Imaginary Part ◽

Initial Permeability ◽

Measured Data ◽

Polycrystalline Ferrite ◽

Grain Sizes ◽

Model Based ◽

Integral Relations ◽

Method Of Evaluation

Abstract The complex initial permeability (CIP) as a function of frequency is one of the main properties of ferrites. This characteristic (CIP) is measured experimentally, therefore there can be found noisy, doubtful or incomplete parts of the spectrum. Thus there is a need for a method of evaluation of quality of CIP. In this article for evaluation of the quality of experimental CIP spectra of polycrystalline ferrite materials the KKR (Kramers-Kronig relations) are used. In order to apply KKR to experimentally measured data (i.e. data with finite limits) the method of transforming these integral relations into summation relations with finite limits is developed and described. This method can be used only for CIP given over the wide frequency rage, so that the imaginary part of CIP is fully presented. Using KKR with the help of CIP spectra model (based on the effects coming from polycrystal grain sizes and defects distribution) partly removes aforementioned limit. Thus with the help of the model we can also make CIP spectra reconstruction (in cases when CIP is noisy or incomplete) and CIP spectra decomposition.

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