Effects of MgO addition on the DC-bias-superposition characteristic of low-temperature-fired NiCuZn ferrites

Microstructure and magnetic properties, especially the DC-bias-superposition characteristic of the MgO-doped and low temperature fired NiCuZn ferrites, were investigated. X-ray diffraction (XRD) patterns showed a single-phase spinel structure for all samples. The microstructure manifested little change with MgO content. Initial permeability, sintered density and saturation magnetic flux density (Bs) monotonously decreased; however, coercive force (Hc) gradually increased with increasing MgO content. MgO addition mode could effectively consider both initial permeability and DC-bias-superposition characteristic of the NiCuZn ferrites. With 1.5 wt% to 2.5 wt% of MgO addition content, the ferrites could obtain high initial permeability of 70-85 with H-70% of 846-700 A/m, indicating good application prospect in the field of chip power magnetic devices.