Glass additive influence on the sintering behavior, microstructure and microwave magnetic properties of Cu-Bi-Zn co-doped Co2Z ferrites

► Bi2O3-B2O3-ZnO-SiO2 glass can effectively wet Co2Z ferrites and promote Co2Z ferrite densification. ► The excess substitution of Bi and Zn (x=0.2) and glass addition enhanced Z phase decomposition into U, W and spinel phases, which resulted in magnetic property degradation. ► 3(Ba0.9Bi0.1O)·2(Co0.8Cu0.2O)·12(Fe1.975Zn0.025O3) ferrite with 2 wt% glass can be densified at below 900 °C and exhibits an initial permeability of 3.4, which provides a promising candidate for multilayer chip magnetic devices for microwave applications.