Magnetic behavior of different modifications in low-fired Z-type polycrystalline hexaferrite

The effect of Ph or Cu modification on the microstructural magnetic charact eristics of Z-type hexaferrites sintered at relatively low temperature with compositions Ba3Co(1-x)CuxFe24O41 and Ba3(1-y) Pb3yCo2Fe24O41 are investig ated. Experimental results show that the reduction of initial permeability mainly results from the decrease of the saturation magnetization and the in crease;of magnetocrystalline anisotropy constant. Progressive studies confi rm that the mechanisms involved in generating these magnetic behaviors are different for Pb- and Cu-modifred Z-type hexaferrites. Proper control of th e sintering conditions is necessary to improve the quality of samples in or der to get excellent magnetic properties. (C) 2000 Elsevier Science B.V. Al l rights reserved.