Permeability Spectral Analysis and Determination of Microstructural Parameters for Mn0.7+xZn0.3SixFe2-2xO4Series

In this communication, the compositional dependence of the real part (mu ') and an imaginary part (mu '') of complex permeability for polycrystalline compositions of ferrite series, Mn0.7+xZn0.3SixFe2-2xO4(x = 0.1-0.3), over the wide frequency and temperature ranges has been discussed. The mu ' decrease with Mn-Si concentration (x) is mainly due to the reduction in saturation magnetization (M-s) and average grain size (D). TheDdecreases due to smaller solid solubility in the spinel structure and segregation of SiO(2)at grain boundaries. The mu '(f) plots at 300 K show a relaxed type of spectra. The observed maximum in the vicinity of Neel temperature in mu '(T) curves is due to the relative rate of change of anisotropy constant andM(s)values, whereas in mu ''(T) plots it is because of the domain wall damping. The derived microstructural parameters related to grain structure have been discussed in a systematic manner.