Effective Complex Permittivity Determination and Microwave Absorption Properties of a Granular Dielectric Composite Material

A novel nano-iron particulate reinforced polymer-based composite material against electromagnetic pollution was prepared for household appliances. The attenuation, permittivity and various absorbing aspects of the composite materials were investigated. Results indicated that the composite materials exhibit promising effects of microwave absorption. The attenuation was affected by volume fraction of nano-iron powders. A single microwave absorption medium won’t be appreciable, and a combination of different microwave absorption materials is suggested.

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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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Complex Permittivity and Microwave Absorption Properties of OPEFB Fiber–Polycaprolactone Composites Filled with Recycled Hematite (α-Fe2O3) Nanoparticles

Polymers ◽

10.3390/polym11050918 ◽

2019 ◽

Vol 11 (5) ◽

pp. 918 ◽

Cited By ~ 3

Author(s):

Ebenezer Ekow Mensah ◽

Zulkifly Abbas ◽

Raba’ah Syahidah Azis ◽

Nor Azowa Ibrahim ◽

Ahmad Mamoun Khamis

Keyword(s):

Microwave Absorption ◽

Complex Permittivity ◽

Microstructural Analysis ◽

High Energy ◽

Fe2o3 Nanoparticles ◽

X Ray Diffraction ◽

Absorption Properties ◽

Microwave Absorption Properties ◽

Transmission Electron ◽

Line Measurement

Recycled hematite (α-Fe2O3) nanoparticles with enhanced complex permittivity properties have been incorporated as a filler in a polycaprolactone (PCL) matrix reinforced with oil palm empty fruit bunch (OPEFB) fiber for microwave absorption applications. The complex permittivity values were improved by reducing the particle sizes to the nano scale via high-energy ball milling for 12 h. A total of 5–20 wt.% recycled α-Fe2O3/OPEFB/PCL nanocomposites were examined for their complex permittivity and microwave absorption properties via the open ended coaxial (OEC) technique and the transmission/reflection line measurement using a microstrip connected to a two-port vector network analyzer. The microstructural analysis of the samples included X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and Fourier transform infrared spectroscopy (FTIR). At 1 GHz, the real (ε′) and imaginary (ε″) parts of complex permittivity of recycled α-Fe2O3 particles, respectively, increased from 7.88 to 12.75 and 0.14 to 0.40 when the particle size was reduced from 1.73 μm to 16.2 nm. A minimum reflection loss of −24.2 dB was achieved by the 20 wt.% nanocomposite at 2.4 GHz. Recycled α-Fe2O3 nanoparticles are effective fillers for microwave absorbing polymer-based composites in 1–4 GHz range applications.

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