New Synthetic Route of Z-Type (Ba3Co2Fe24O41) Hexaferrite Particles

Z-type barium hexaferrite particles were synthesized by a one-step mixing-calcination process (MCP) and its magnetic properties were characterized and compared to the sol-gel (SGP) and the conventional ceramic (CCP) processed Z-type Ba hexaferrite with two-step calcination. We have used 71.2% pure M-type (BaFe12O19) and 83.8% pure Y-type (Ba2CO2Fe12O22) precursors to synthesize Z-type by the MCP. As a result, 77.8% pure Co(2)Z hexaferrite particles were obtained. The purities of Co(2)Z hexaferrite particles processed by SGP and CCP were 75.1% and 70.7%, respectively. It was found that purity of Z-phase was controllable by purity of M- and Y-type precursor particles in the MCP. Loss tan 6 of sintered MCP Co(2)Z decreased from 0.17 at 50 MHz to 0.068 at 300 MHz, while loss tan delta of sintered SGP and CCP Co(2)Z were 0.12 and 0.09 at 300 MHz. It is found that this loss tan delta is controllable by the purity of Z-phase and sintering process. These results imply that our new process is potentially applicable to synthesis of any other hexaferrites and also cost-effective.