The Effects of Size and Shape of Iron Particles on the Microwave Absorbing Properties of Composite Absorbers
| Autor: | Chung-Kwei Lin, Siu Tong Choi, Ruey-Bin Yang, Wen-Fan Liang |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
chemistry.chemical_classification
Permittivity Materials science Reflection loss Composite number Polymer Epoxy Space charge Electronic Optical and Magnetic Materials chemistry Permeability (electromagnetism) visual_art visual_art.visual_art_medium Electrical and Electronic Engineering Composite material Microwave |
| Zdroj: | IEEE Transactions on Magnetics. 49:4180-4183 |
| ISSN: | 1941-0069 0018-9464 |
| DOI: | 10.1109/tmag.2013.2239973 |
| Popis: | High values of magnetic permeability and dielectric permittivity of polymer composite containing flake-shaped iron particles were prepared by the mechanical milling of two batches of iron powders [Fe(A) and Fe(B)] under controlled conditions. The frequency-dependent complex permittivity (e'-je") and permeability (μ'-jμ") of resin composites with 40 wt.% of flake-shaped iron particles are investigated in 2-18 GHz. The results show that all e', μ', μ" substantially increase due to the increase of milling time and the size of the flake-shaped particles. The enhancement of space-charge polarization increases the permittivity of the composite absorbers. The frequency dispersion μ" of of flake-shaped Fe/epoxy composites show a higher resonance frequency (around 3 GHz) which exceeds the Snoek's limit in the gigahertz range due to their low eddy current loss coming from the particle shape effects. For 40 wt.% composite with 2 mm thickness, the predicted reflection loss reaches -19.4 dB at 14.9 GHz for Fe(A)/2 hr, -28.0 dB at 8.96 GHz for Fe(A)/4 hr, -31.6 dB at 11.6 GHz and -42.9 dB for Fe(B)/2 hr at 7.84 GHz for Fe(B)/4 hr as magnetic fillers. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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