Special Issue Description


Authors : U. B. Hatwar, M.N.Giriya , K.G.Rewatkar, V.M.Nanoti

Page Nos : 19-24

Description :
Abstract: Strontium hexaferrite of a structural formula SrAl2Fe10-2x(CoZr)xO19, where (x= 0.6, 1) have been synthesized by microwave induced sol gel auto combustion technique. The dielectric constant, dielectric loss tangent and magnetic properties were studied. The dielectric constant and dielectric loss tangent were measured in the frequency range of 1KHz to 99KHz at room temperature. The dielectric constant decreased with increasing frequency for all the samples. This behavior of dielectric properties with frequency has been explained with the Maxwell-Wagner type interfacial polarization in agreement with the Koop’s phenomenological theory. The substitution of Co and Zr ions in SrAl2Fe10-2x(CoZr)xO19 increases the value of the dielectric constant. This increase in dielectric constant could be due to the electronic exchange between Fe2+ ↔ Fe3+ and results in a local displacement determining the polarization of the ferrites. For these ferrite samples the Curie temperature increases as Co and Zr ions substitution increases. Key words: Hexagonal ferrites, Dielectric constant, Dielectric loss tangent, Curie temperature.

Date of Online: 30 Special Issue-2, Feb. 2015