Nanocomposites and nanomaterials

Effect of magnetic fillers and their orientation on the electromagnetic properties of BaFe12-xGaxO19 (x=0.1-1.2)–epoxy composites within GHz range
Yakovenko O.S.1, Matzui L.Yu.1, Vovchenko L.L.1, Lazarenko O.A.1, Syvolozhskyi O.A.1, Oliynyk V.V.1, Zagorodnii V.V.1, Borovoy M.O.1, Tesel’ko P.O.1, Trukhanov A.V.2, Trukhanov S.V.2
1 Taras Shevchenko National University of Kyiv, Volodymyrs’ka str., 64/13, Kyiv, 01601, Ukraine.
E-mail: alenka-ya@ukr.net
2 Scientific-Practical Materials Research Centre of the National Academy of Sciences of Belarus, P.Brovki str., 19, Minsk, 220072, Belarus.

BaFe12-xGaxO19 is related to M-type hexagonal ferrites which are widely used as electromagnetic (EM) materials and are perspective for application in the centimeter spectral range due to their large values of permeability and magnetization as well as their good dielectric properties at these frequencies [1–2].
The aim of this work was to investigate the influence of magnetic filler type, content and orientation on EM properties of the BaFe12-xGaxO19 (x=0.1-1.2)–epoxy composites (CMs) in 26-37 GHz frequency range. A part of the investigated CMs was cured under the action of a magnetic field. The orientation of magnetic filler in CMs was evidenced by SEM and XRD methods. Microwave network analyzers P2-65 and P2-68 were used for measurements of frequency dependencies of transmission and reflection loss spectra of samples at room temperature.
The results demonstrate that the presence of BaFe12-xGaxO19 in epoxy matrices leads to an increase in the EM characteristics of CMs. The EM properties of the CMs are dependent on magnetic filler content, its type and orientation and the improvement of evaluated characteristics with increasing content of ferrite was achieved. These results can be used, for ins., in the design of microwave absorbers.

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