Microwave absorption characteristic of a double-layer X-band absorber based on MWCNTs/La0.6Sr0.4Mn0.5Fe0.5O4 coated with PEDOT polymer

Microwave absorption characteristics of double layer of barium hexaferrite attached on the silica to from a composite on the basis of wave propagation theory have been investigated. Barium hexaferrite, BaFe12O19, was synthesized through ceramic method from stoichiometric mixtures of BaCO3 and Fe2O3 as precursors. The mixture was pelletized under the pressure of 10 MPa and sintered at 1100 °C for 5 hours. Silica in the forms of powder was purified by using HCl. The crystal structure of the samples was characterized using X-ray diffraction (XRD), microstructure was examined using scanning electron microscope (SEM), hysteresis curves recorded by PERMAGRAPH techniques, whereas the microwave absorbing properties for X-band was recorded using a vector network analyzer (VNA). Relative complex permeability and permittivity, and reflection loss values were calculated at given thickness according to transmittance line theory within the range 8.2–12.4 GHz. Based on this study, the layer dimension and frequency that results in low reflection loss can be estimated from the material properties of the barium hexaferrite/silica composite material.

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Complex Permittivity, Permeability and Microwave Absorption Studies of Double Layer Magnetic Absorbers Based on BaFe12O19 and BaFe10CoZnO19

Materials Science Forum ◽

10.4028/www.scientific.net/msf.966.302 ◽

2019 ◽

Vol 966 ◽

pp. 302-307

Author(s):

Erfan Handoko ◽

Iwan Sugihartono ◽

Mangasi Alion Marpaung ◽

Ucu Cahyana ◽

Sovian Aritonang ◽

...

Keyword(s):

Microwave Absorption ◽

Double Layer ◽

Complex Permittivity ◽

Network Analyzer ◽

X Ray Diffraction ◽

Absorption Properties ◽

Microwave Absorption Properties ◽

Matching Layer ◽

X Band ◽

Absorption Studies

Microwave absorption properties of double layer magnetic absorbers based on BaFe12O19 (BFO) and BaFe10CoZnO19 (BFCZO) have been investigated in X-band (8.2–12.4 GHz) frequencies. The BFO and BFCZO were prepared by using a solid state reaction process. The crystalline structures were investigated by X-ray diffraction (XRD), The complex permittivity and permeability are determined using Vector Network Analyzer (VNA) in a range from 8.2 GHz to 12.4 GHz. The double layer magnetic absorbers, composed of the BFO as matching layer and the BFCZO as absorption layer, with a total thickness of 5 mm, showed an effective reflection loss (RL) an effective absorbing bandwidth below –5 dB.

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Microwave Absorption Characteristic of ZnNd(x)Fe(2-x)O4 System

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.855.280 ◽

2020 ◽

Vol 855 ◽

pp. 280-285

Author(s):

Mashadi ◽

Andhika Ajiesastra ◽

Yunasfi

Keyword(s):

Microwave Absorption ◽

Morphological Observation ◽

Absorption Characteristic ◽

X Ray Diffraction ◽

High Frequencies ◽

Detection Systems ◽

Uniform Particles ◽

X Band ◽

Ion Substitution ◽

Diffraction Patterns

The ZnNd(x)Fe(2-x)O4 (x = 0.0; 0.010; 0.020 and 0,030) systems were synthesized by solid reaction method from a mixture of ZnO2, Fe2O3 and Nd2O3 powders according to their mole ratio using mechanical milling techniques. In this mixture was added ethanol of 25 ml and then milled for 5 hours, after that sintered at a temperature of 1000 °C for 5 hours. X-ray diffraction patterns showed that the Nd3+ ion substitution in ZnFe2O4 with the concentration of x = 0.0 to 0.02 did not result in changes in ZnFe2O4 phase with cubic structure (space group of Fd-3m). However, the composition of x = 0.030 formed multiphases ZnFe2O4 and NdFeO3 phases. The morphological observation using Scanning Electron Microscope (SEM) showed spherical and uniform particles. Whereas the microwave absorption capability of the sample ZnNd(x)Fe(2-x)O4 system increased with the increasing concentration of x from 91.20% up to 97.80% with the highest absorption is found at a frequency of 10.24 GHz. The dielectric loss of this study is very small around 0.005 up to 0.05. It is hoped that the compound ZnNd0.02Fe1,98O4 can be applied to microwave absorbing agents at high frequencies (X-band range) in antiradar detection systems.

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