Authors : S. R. Gawali and P. R. Moharkar
Page Nos : 131-137
Description :
The sol–gel auto-combustion technique was adopted to synthesize single-phase nanosized M-type hexagonal ferrites (NHFs) with the composition of CaAlxFe12-xO19 (x=2, 4 and 6). The structural properties of the synthesized samples were carried out by XRD analysis. The XRD analysis revealed that the samples are a single phase M-type hexagonal ferrite. The lattice parameters, Cell volume, X-ray density and bulk density porosity of samples were found to be decreasing with increase in the substitution of aluminium whereas the porosity of the samples increases with increase in the substitution of aluminium. The average particle size of the samples measured by TEM is found to be in the nano-range. The dielectric constants (ε′) of the samples were measured at fixed frequency of 1 MHz with different temperature. The dielectric constant of the samples increases with increase in temperature. The dielectric constant decreases with increase in concentration of Al3+ ions in substituted NHFs accompanied by an increase in the electrical resistivity are suitable trends for applications in the microwave devices.
