Correlating the microstructure with magnetic properties of Ti-doped high-frequency MnZn ferrite

In this study, high-frequency MnZn ferrites are prepared for power applications at 10 MHz using solid-state reaction method. The sample doped with 3000 ppm TiO2 yields the optimal comprehensive magnetic properties, with an initial permeability of 792, power loss of 415 kW/m3 (10 MHz, 5 mT, 25 ℃), and saturation induction of 460 mT. This indicates significant progress compared to previously reported results. The mechanisms of property optimisation, microstructure and domain structure evolution also discussed with TiO2 doping. The precipitation of Ti at the grain boundary can promote a high-density microstructure and favour the formation of magnetic monodomain in MnZn ferrites. Our results elucidate the correlations between microstructure, domain structure, and high-frequency performance, and present a potential roadmap for the development of high-frequency soft magnetic ferrites.