Radar absorbing properties of polyvinyl alcohol/Ni–Zn ferrite-spinel composite

The electromagnetic and radio-absorbing characteristics of ferrite-polymer composites with conductive inclusions based on polyvinyl alcohol are investigated. The Ni–Zn spinel ferrite powder of 2000NN grade with composition Ni$_{0.32}$Zn$_{0.68}$Fe$_2$O$_4$ was used as filler. It is shown that the obtained composites are effective absorbers in the frequency range of 2–5 GHz with peak reflection loss less than $\sim$20 dB. Through the analysis of the permittivity spectra and permeability spectra, as well as the calculated re- flection loss spectra, critical factors of the electromagnetic wave absorption in obtained composites are established.