Intergranular Capacitance of Sintered BaFe12O19 Doped with TiO2 in the very Low Frequency Region

Abstract

A powder of BaFe12O19 composition (barium hexaferrite) was prepared by using the respective mixture of metal oxides and performing a solid-state reaction at 1000 °C/4h in air. The obtained barium hexaferrite powder was milled for a prolonged time in the planetary ball mill and agate mill to achieve submicron powder. The BaFe12O19 submicron powder was mixed with TiO2 nanopowder as a dopant. The prepared powder mixture was characterized by using XRD and SEM techniques. After that, the barium hexaferrite powder mixture was pressed into thin and small diameter size disk-shaped samples and sintered at different sintering profiles from 1050 °C to 1275°C/2h to 6h. The sintered samples were also characterized by using XRD and SEM. The main electrical properties such as capacitance (intergranular) and bulk resistance R at 1 Hz to 100 Hz were measured at room temperature. The dielectric permittivity was calculated from the equivalent scheme of disk capacitor. The obtained results were used for observing space charge relaxation effects and development of multilayer capacitor forenergy storage device.