A series of pure stoichiometric and 1 wt% lead borosilicate (PBS) glass added MgCuZn ferrite with the general formula Mg0.5Cu xZn0.5-xFe2O4 with x = 0.05, 0.1, 0.15, 0.2, 0.25 and 0.3 were synthesized by microwave sintering technique. Single phase spinel structure is exhibited by the XRD patterns of these ferrites. DC and AC conductivity were investigated as a function of composition, temperature and frequency. DC conductivities were also estimated using the impedance spectroscopy analysis of Cole-Cole plots. The DC conductivities thus obtained are in good agreement with the experimental results. All the investigated samples exhibited two regions of conductivity one in the low temperature and the second in the high temperature region. It is observed that PBS glass added samples have lower conductivities than pure samples. Due to their lower conductivities and sintering temperatures the 1 wt% PBS glass added samples are suitable for multilayer chip inductor (MLCI) and high definition TV deflection yoke material application. © 2013 Elsevier B.V. All rights reserved.

Madhuri W

Department of Physics

School of Advanced Sciences

Vellore Campus

Vemuri Rama Krishna Murthy

Penchal Reddy M

Kim I.G

Rama Manohar Reddy N

Siva Kumar K.V

Murthy V.R.K.

HIGH-DEFINITION TV

Impedance spectroscopy

MATERIAL APPLICATION

Microwave sintering

MULTILAYER CHIP INDUCTORS

Polaron hopping

SINGLE-PHASE SPINEL STRUCTURE

Sintering temperatures

DIGITAL TELEVISION

Electric Impedance

FERRITES

Glass

Heat conduction

High definition television

Microwave heating

Sintering

Transport properties

Borosilicate glass

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

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VIT University

Materials Science and Engineering B: Solid-State Materials for Advanced Technology

Microwave sintered magnesium ferrite (MF) nanoparticles are synthesised by hydrothermal technique. X-ray diffraction revealed pure spinel phase but low crystallinity. Synthesised MF is observed to be in nanoscale under scanning electron and transmission electron microscopes. MF is characterised further by Fourier transform infrared and UV-visible spectrometers for vibrational bands and optical band gap information. Electric and magnetic characterizations revealed low conductivity, dielectric loss, magnetic loss and fairly good initial permeability. High coercivity and M-H loop area of MF indicate the hard magnetic nature. © 2019, Springer Science+Business Media, LLC, part of Springer Nature.

Journal of Superconductivity and Novel Magnetism

Effect of Microwave Heat Treatment on Hydrothermal Synthesis of Nano-MgFe2O4

The effect of iron deficiency on the structural, electrical and magnetic properties of the nano PbFe12-xO19-δ (where x = 0.0, 0.25, 0.50, 0.75 and 1.0) hexaferrites prepared by sol-gel auto combustion and further processed by microwaves is presented. The structure studied using transmission electron microscope (TEM) showed hexagonal cylindrical particles with an average size of ∼20 nm. Selected area electron diffraction (SAED) reflected highly crystalline nature of these nanoparticles. From the dielectric characterizations ac-conductivity, dielectric constant and loss tangent are analysed for pure and modified PbFe12-xO19-δ hexaferrites. The magnetic analysis revealed the formation of single-domain structure. Saturation magnetization (MS) decreases from 63.2 (x = 0) to 38.2 (x = 1.0) emu/g with increasing the Fe ions deficiency. Room temperature Mössbauer spectra show five sextets for all compositions confirmed the single phase formation. The relative area of 12k (↑) site decreases and 4f2 (↓) increases drastically with increasing the Fe ions deficiency in Pb-hexaferrites. © 2018 Elsevier B.V.

Materials Chemistry and Physics

Effect of non-stoichiometry in lead hexaferrites on magnetic and dielectric properties

Journal of Materials Science: Materials in Electronics

Chemical composition of Li(4−2x)NixTi2O6 by sol–gel method and microwave processing

The effect of iron deficiency on the structural, electrical, ferroelectric and magnetic properties of nano PbFe12-xO19-δ (where x=0.0, 0.25, 0.50, 0.75, 1.0) hexaferrites prepared by sol-gel auto combustion and processed by microwaves are investigated. X-ray analysis confirms single phase magneto-plumbite phase formation. The surface morphology is studied from Field Emission Scanning Electron Microscope. Further, optical properties are investigated using Fourier Transform Infrared spectra and UV–visible spectra. AC electrical conductivity is estimated as a function of temperature and frequency in the range of room temperature (RT) to 500 °C and 100 Hz to 5MHz. AC electrical conduction analysis shows that conduction is mainly due to small polaron hopping mechanism. The variation of polarization with applied electric field exhibits hysteresis loop confirming the ferroelectric nature. The initial permeability studies with varying temperature reveals that the Curie transition temperature for the present series is around 400 °C. Variation of initial permeability with frequency ranging from 100 to 5 MHz shows a constant value (except for x=0.0) opening avenues for high frequency applications. © 2017 Elsevier B.V.

Journal of Magnetism and Magnetic Materials

Multiferroic properties of microwave sintered PbFe 12−x O 19−δ

Lately ferrites find applications as multilayer chip inductor (MLCI) cores. During the MLCI fabrication, the core has to be sintered with an internal electrode like silver. The sintering temperature of ferrites can be reduced in many ways. In the present study, two techniques are simultaneously used for the purpose vice doping of glass and choosing to sinter using microwaves. Undoped and lead borosilicate glass-doped MgCuZn ferrites with generic formula Mg0.5Cu x Zn0.5-x Fe2O4 at x = 0.05-0.3 were synthesized by conventional solid state reaction route and were characterized for structural, surface, and magnetic properties. From X-ray diffraction studies, it was found that all the undoped and glass-doped samples were single-phase spinel structure. Glass-doped MgCuZn ferrite samples exhibited lower permeability than that of undoped MgCuZn ferrites. However, a flat frequency response was observed in the glass-doped Mg0.5CuxZn0.5-xFe2O4 samples at x = 0.1 and 0.2. © 2016 Australian Ceramic Society.

Journal of the Australian Ceramic Society

Effect of glass on magnetic properties of microwave-processed MgCuZn nano ferrites

Polycrystalline MgCuZn ferrites with chemical formula Mg 0.50-xCuxZn0.50Fe2O4 (x = 0.00, 0.05, 0.10, 0.15, 0.20, 0.25 and 0.30) were prepared by microwave sintering method. These powders were calcined, compacted and sintered at 950 °C for 30 min. Structural, microstructural and elemental analyses were carried out using X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray spectrometry (EDS), respectively. The lattice parameter is found to increase with increasing copper content. A remarkable densification is observed with the addition of Cu ions in the ferrites. The sintered ferrite was characterized for initial permeability, dielectric constant and dielectric loss tangent and ac conductivity measurements. The temperature variation of the initial permeability of these samples was carried out from 30 °C to 200 °C. The dielectric constant, dielectric loss tangent and ac conductivity have been measured in the frequency range of 100 Hz to 1 MHz. Initial permeability and dielectric constant were found to increase and dielectric loss decreased with Cu substitution for Mg, up to x = 0.20. The ferrite powder prepared is suitable for the application in multilayer chip inductor due to its low-temperature sinterability, good magnetic properties and low loss at high frequency. © 2010 Elsevier B.V.

Materials Science and Engineering C

Influence of copper substitution on magnetic and electrical properties of MgCuZn ferrite prepared by microwave sintering method

Mg0.40Cu0.10Zn0.50Fe1.95O 4-δ ferrite samples were prepared by the microwave sintering (MS) and conventional sintering (CS) techniques. The samples were then characterized by the x-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive x-ray spectrometry (EDS) techniques. All the compositions showed single-phase cubic spinel structure. The lattice constants of MS samples were found to have lower magnitude than those of CS samples. The densities of microwave-sintered samples were higher than those of conventionally sintered samples. The temperature dependence of initial permeability was studied in the temperature range 30-150 °C at 10° temperature intervals. It was noted that the initial permeability of MgCuZn ferrites prepared by the MS method was higher than that of MgCuZn ferrites prepared by the CS method. The initial permeability (μi) magnitude of about 2300 at 10 kHz is achieved for microwave-sintered (Mg0.40Cu0.10Zn 0.50Fe1.95O4-δ) ferrite, at only 950 °C sintering temperature. In addition, the sintering time of ferrites was reduced from 5 h to 20 min by using the MS technique. The low-temperature- sintered MgCuZn ferrites prepared possess good electromagnetic properties, as well as good microstructure, thus making them suitable materials for multilayer chip inductors (MLCIs) having high performance and low cost. © 2010 The Royal Swedish Academy of Sciences.

Physica Scripta

Microwave sintering of high-permeability MgCuZn ferrite at low sintering temperatures suitable for microinductor applications

New Physics: Sae Mulli

Editing and Publishing Activities of the Korean Physical Society during the First Fifty Years Since Its Inauguration in 1952

Defect and Diffusion Forum

Synthesis and Characterization of Novel Nanoceramic Magnesium Ferrite Material Doped with Samarium and Dysprosium for Designing – Microstrip Patch Antenna

Journal of Alloys and Compounds

AC impedance studies on LiFe5−xMnxO8 ferrites

Transport properties of microwave sintered pure and glass added MgCuZn ferrites

Journal	Materials Science and Engineering B: Solid-State Materials for Advanced Technology
ISSN	09215107
Open Access	No