Complex permeability and permittivity, and microwave absorption studies of Ca(CoTi)xFe12−2xO19 hexaferrite composites in X-band microwave frequencies

The microwave absorption studies of hexaferrite composites prepared with [Ca(CoTi)xFe12−2xO19]96.0[La2O3]4.0 (x varying from 0.0 to 1.0 in steps of 0.2) were made in the frequency range from 8.0 to 12.4 GHz. The reflection loss has been studied as a function of frequency, composition and thickness of coating. The relationship of reflection loss with complex permeability (μ′−jμ″) and dielectric constant (ε′−jε″) of composites have been investigated in the X-band of microwave frequencies. The theoretically determined matching frequency has been compared with an experimentally measured value at minimum reflection loss. The multifrequency measurements of μ* and ε* were made by the reflection/transmission technique.