Complex Y-type hexagonal ferrites: an ideal material for high-frequency chip magnetic components

The magnetic properties of complex Y-type hexaferrites series with Ba2Me2Fe12O22 (Me Zn, Co, Cu) have been investigated. Y-type polycrystalline hexaferrite powders prepared by the solid-state reaction method were characterized by X-ray diffraction and vibrating sample magnetometer. Permeabilities of the samples were investigated using an impedance analyzer. Experimental results show that the substitution of Co for Zn leads to a decrease of saturation magnetization and an increase of magnetic anisotropy. At room temperature, saturation magnetization does not increase linearly as Zn content increases due to the effect of the thermal agitation. The saturation magnetization and magnetic anisotropy of the sample determine the variation of initial permeability. Cu additions can lower the sintering temperature distinctly as the magnetic properties debase slightly. It is shown that these materials should be promising for next generation of high-frequency chip magnetic components (including chip inductors and chip EMI filters). (C) 2003 Elsevier B.V. All rights reserved.