Microstructure and electromagnetic properties of low-temperature sintered NiCuZn ferrite by co-doped Bi2O3 and Co2O3

In this work, the electromagnetic of NiCuZn ferrite was enhanced and the sintering temperature was decreased by co-doped Bi 2 O 3 and Co 2 O 3 . The influence of the doping concentration of Co 2 O 3 on the microstructure and magnetic properties of NiCuZn ferrite was studied. Characterizations display that the high density and uniform microstructure of NiCuZn ferrite was obtained at a low sintering temperature of 925 °C. The Co ions were doped in the octahedral B-sites and decreased lattice constant and grain size. The resistivity was also improved after doping appropriate Co ions for the decrease of the Fe 2+ . The saturation magnetization, coercivity, permeability, and cut-off frequency were also enhanced after being doped with the Co 2 O 3 . Consequently, the NiCuZn ferrite doped with 0.30 wt% Bi 2 O 3 and 0.4 wt% Co 2 O 3 possesses a saturation magnetization of ~ 60.014 emu/g, coercivity of ~ 0.033 kA/m, real part of permeability of ~ 269.9 @ 1 MHz, and high cut-off frequency of 8.08 MHz, which can be applied in multi-layer chip inductors.