Synthesis and magnetic properties of core-shell structured Finemet/NiZn ferrite soft nanocomposites by co-precipitation

Finemet/NiZn ferrite core-shell particles and toroid core have been synthesized by co-precipitation method combined with following compact pressure and high temperature sintering process. The toroid core were produced from these particles by mold compacting with a compact pressure of 1400 Mpa at room temperature, then sintered at 600 °C for 1 h. The SEM results indicated that a layer of ferrite was uniformly coated on the surface of Finemet particles, with the increase of ferrites thickness, the permeability, saturation magnetization and magnetic loss of toroid core decrease, and the toroid core with 5 wt% ferrites shows excellent soft magnetic properties. It exhibits a high permeability of 56, high saturation magnetization of 127.1 emu/g and lower core loss of about 1.51 w/kg at 100 kHz and 50 mT.