Dielectric and Magnetic behaviour of Substituted Strontium M-Hexagonal Ferrite

Abstract

SrFe12O19 is an important magnetic hexa-ferrite which is used for high frequency application in multilayer chip inductor. Generally BaFe12O19 is used for such high frequency applications but it has been observed that SrFe12O19 has better magnetic properties than the prior at high frequency range. This project concentrates on the preparation of SrFe12O19 samples along with other samples with substitution of Zn and Ti in the base composition and to study the changes in magnetic property due to these substitutions. All the products were synthesized via auto-combustion process. All the samples were characterized for their phase formation using XRD. The powders obtained by auto-combustion process were calcinated at 900oc and then pressed into pellets and toroid samples. A dilatometry test was also carried out for bar shaped rectangular samples. These pellet and toroid samples were sintered at various temperatures. After sintering, these samples were characterized for their microstructural development, dielectric and magnetic properties. The dielectric and inductive property measurements were carried out by the help of a LCR meter. It has been observed that on introduction of Zn and Ti in SrFe12O19 and also the use of sintering additives like CuO gives better dielectric and magnetic properties than the undoped sample.