Electrical transport properties and temperature-dependent magnetization behavior of TbZn-substituted Ca0.5Ba0.5Fe12O19 hexaferrites

Substitution of TbZn in the series of Ca0.5Ba0.5-x Tb (x) Zn (y) Fe12-y O-19 (x = 0.00-0.10; Y = 0.00-1.00) hexaferrites prepared by sol-gel method and their effect on the structural, electrical and magnetic properties are investigated. Temperature-dependent magnetic behaviors of selected samples are observed up to the magnetic field of 8T taken over temperature ranges from 4.2 to 373 K. The coercivity of the samples decreases from 2740 to 1370 Oe with increasing temperatures in a linear fashion up to 373 K. The grain boundaries and the associated pinning fields seem to have an important role in the magnetic behavior of these hexaferrites. The resistivity of ferrite decreases from 24 x 10(8) to 15 x 10(8) Omega-m. The temperature dependence of resistivity and mobility exhibits the degenerate-type semiconductor-like behavior of these ferrites. The dielectric constant and dielectric loss decrease and show relaxation behavior at higher frequencies.