The effect of Zn ion substitution on electromagnetic properties of low-temperature fired Z-type hexaferrite

The influence of Zn substitution on the densification, microstructure, lattice parameters and electromagnetic properties of planar Z-type hexaferrites, which have stoichiometric composition of Ba3Co2(10.8−x)Zn2xCu0.4Fe24O41, were investigated. The results show that the Zn2+ substitution has no obvious effect on the densification, but Z-type hexagonal phase can form and demonstrate typical planar anisotropic characteristics of soft magnetic materials (σr⩽6.20 emu/g) in the range of x⩽0.25. The of lattice parameters of planar a (0.588 nm) and axial c (5.25 nm) remain stable. At the certain temperatures, the sintered hexaferrites with an optimal density of about 4.62 g/cm3 show better electromagnetic properties for x=0.15 than the samples without Zn2+ incorporation: initial permeability of about 9.0, cut-off frequency of above 800 MHz, resisitivity of above 3.20 Ω cm and dielectric constant of less than 35.