Crystalline phases and magnetic properties of Cu–Bi–Zn co-doped Co2Z ferrites

The effects of Cu, Bi and Zn substitutions on the crystalline phase and magnetic properties of hexagonal ferrites with a composition of 3(Ba1−xBixO)2(Co1−yCuyO)12(Fe2-(x/4)Zn(x/4)O3) were investigated. The results showed that the addition of Bi and Zn can significantly promote Z phase formation. The Z phase may be triggered to decompose into U and W phases resulting from the evaporation of Bi and segregation of Co-rich ferrites at high sintering temperatures for samples with large amounts of Bi and Zn. The initial permeability decreased with increasing x value because the Bi substitution promoted Z phase decomposition into U and W phases.

Research highlights▶ The effects of Cu, Bi and Zn substitutions on the crystalline phase and magnetic properties of hexagonal ferrites with a composition of 3(Ba1−xBixO)2(Co1−yCuyO)12(Fe2-(x/4)Zn(x/4)O3) were investigated. ▶▶ The results showed that the addition of Bi and Zn can significantly promote Z phase formation. ▶ The Z phase may be triggered to decompose into U and W phases resulting from the evaporation of Bi and segregation of Co-rich ferrites at high sintering temperatures for samples with large amounts of Bi and Zn. ▶ The initial permeability decreased with increasing x value because the Bi substitution promoted Z phase decomposition into U and W phases.