N. Wu, Q. Wei, in
, 2012
5.5.4 Microwave absorption
Chen
et al.65 fabricated the highly aligned array of Fe3O4/carbon
(CNT) coaxial
and doped them in poly (methyl methacrylate) matrix under a low magnetic field. The results showed that microwave absorption of the magnetically aligned composite at 8.5–12.5 GHz was evidently enhanced. Park
et al.66 fabricated the single-layered microwave absorbers employing both
and magnetic lossy materials. CNFs were used as dielectric lossy materials and NiFe particles were used as magnetic lossy materials. An evaluation of their radar absorbing performance in the range of 2–18 GHz revealed that the mixed single-layered
(RAMs) had improved absorbing characteristics with thinner matching thicknesses.
The mixed RAM showed the 10 dB absorbing bandwidth of 4.0 GHz in the X-band (2.00 mm thickness) and 6.0 GHz in the Ku-band (1.49 mm thickness). Lamastra
et al.67fabricated the porous, highly interconnected architecture and randomly oriented CoFe2O4 /mutiwalled carbon nanotube (MWCNTs) composite nanofibers using
. The prepared nanofibrous composites are expected to exhibit improved microwave absorption due to the better match between the dielectric loss and magnetic loss. In order to achieve a higher absorbance in the 8–20 GHz range, Nanni
et al.68 dispersed CNFs into an epoxy resin matrix. The CNFs were chosen as a way of lowering filler content, while increasing the
of the resulting composite. The resulting microstructures, composed of well-dispersed CNF, as well as of microaggregates, led to materials of equal filler content which displayed different dielectric properties and absorbing performances.