Effect of B₂O₃ addition on the sintering behaviors and magnetic properties of Co₂Z-type hexagonal ferrites

The effects of B₂O₃ concentration and Cu²⁺-substitution on the densification, phase structure and magnetic properties of Co₂Z-type hexaferrite were investigated. The results showed that Z-type phase and M-type phase were co-existed in the sample and the volume of M-type phase increased and initial permeability decreased with the increasing of B₂O₃ concentration. By incorporating with B₂O₃ and Cu²⁺-dopants the Co₂Z-type hexaferrite could be well sintered at 950°C with bulk density of 5.02 g/cm³, μ′ = 2.5 and the relative density was up to 94%. These improvements had made the material suitable for fabrication low-temperature sintering of Multilayer Chip Inductors for high frequency application.