PREPARATION AND IDENTIFICATION OF SOME FERRITES IN NI-CO-MN-ZN SYSTEM

A series of ferrite compositions based on Ni, Co, and Mn, with Zn as a partially substituting ion, have been prepared by a coprecipitation r oute using NH4OH as the precipitating agent and the materials characte rised for purity and stoichiometry by X-ray diffraction, X-ray fluores cence, and energy dispersive X-ray analysis. Because of complex ion fo rmation between the metal and ammonium ions, loss of metal for precipi tation occurs lending to differences between the desired and achieved stoichiometries. The experimental conditions relating to solution pH, complex ion formation, and the associated metal loss have been studied for the preparation of specific compositions. The use of the co-preci pitation route is shown to allow preparation of ferrites at low sinter ing temperatures. (C) 1995 The Institute of Materials.