PHASE-STABILITY AND IONIC TRANSFERENCE NUMBER OF A MN-ZN SPINEL FERRITE

The phase stability region of a MnZn ferrite, Mn0.54Zn0.35Fe2.11O4, ha s been determined from the isothermal variation of the total conductiv ity with oxygen partial pressure at elevated temperatures and its mean ionic transference number via Tubandt-type electrotransport experimen ts in the entire stability range of the ferrite. The ionic transferenc e number increases with increasing oxygen partial pressure in oxidizin g atmospheres and with decreasing oxygen partial pressure in reducing atmospheres, which is in accord with the Frenkel disorder as the major ity defect type.