Effect of Si on the dielectric properties of Nix Zn1-x Fe­2O4 as a function of composition and frequency

Abstract

Nickel-zinc ferrites of composition Ni_xZn_1-xFe₂O₄ (x=0.66, 0.77, 0.88, 0.99) were prepared by the usual ceramic technique. The dielectric properties have been studied as a function of composition and frequency. It is observed that the values of dielectric constant є' and dielectric loss factor tanδ for samples prepared in the present work are much lower and of reduced price than those commercially obtained Ni-Zn ferrites. These low values are attributed to the presence of Si in Fe₂O₃ powder. It has been found that the ceramic grain growth was suppressed by Si, which results in a decrease in the dielectric constant and dielectric loss factor. The dielectric constant є' and loss tangent tan δ also decrease as the frequency of applied ac electric field increases.