Co2Z type hexagonal ferrites prepared by sol–gel method

Synthesis of Co2Z type hexagonal ferrites and a low-temperature sintering were studied. Co2Z phase was formed at 1350 °C by a conventional process with some residual Co2Y phase. Co2Z phase was first formed at 1300 °C by a sol–gel process and the single phase was formed at 1350 °C without any other phases. Bulk densities of sintered Co2Z bodies increased with increasing Bi2O3 and CuO contents. Specimens prepared with the sol–gel process showed significantly higher initial permeabilities than with the conventional process. The average grain size and density of specimens sintered at the low temperature (900 °C) increased gradually with increasing Bi2O3 and CuO contents.