Introduction of NiZn-Ferrite Into Co $_{2}$ Z-Ferrite and Effects on the Magnetic and Dielectric Properties

Various amounts of NiZn spinel ferrite (Ni_0.5Zn_0.5Fe₂O₄) were introduced into Co₂Z hexagonal ferrite (Ba₃Co₂Fe₂₄O₄₁ ) by a solid-state reaction method. The phases, microstructures, and magnetic and dielectric properties have been investigated. The results show that the grain size is obviously changed with introducing of NiZn ferrite, and the saturation magnetization increases from 45 emu/g to 55 emu/g. Compared with undoped Co₂Z ferrite, the samples doped 15 wt % and 20 wt % NiZn ferrite exhibit much stable μ^´ and ε^´ spectrums with frequency. The quality factor is improved to about 80 and the dielectric loss is reduced to 0.005 at 100 MHz.