The preparation and microwave properties of BaZn2−ZCoZFe16O27 ferrite obtained by a sol–gel process

BaZn2−ZCoZFe16O27 hexaferrites with Z=0.0,0.6,0.9,1.5 and 2.0 have been prepared at 1200 °C for 5 h by the citrate sol–gel process. The complex dielectric constant and complex permeability of hexaferrite-paraffin wax composites have been measured by the transmission/reflection coaxial line method in the range from 100 MHz to 6 GHz. Results show that both the complex dielectric constant and dielectric loss exhibit no significant change, with dielectric loss values near to zero in the whole measuring frequency range. It also has been shown that the real part of permeability decreases with the increase of frequency for all samples, whereas the imaginary part increases with the frequency until reaching a peak value, after which it decreases again for samples with Z=0.0,0.6,0.9 and 2.0. Substitution of zinc ions substantially affects the microwave properties of BaZn2−ZCoZFe16O27 ferrites.