Equilibrium Atmosphere Schedules for the Cooling of Ferrites

Abstract

Phase diagrams including contour lines of constant ferrous ion content in oxygen-partial-pressure vs temperature coordinates were determined for two MnZn ferrites and two NiZn ferrites containing excess iron. A “universal” equilibrium atmosphere diagram which is applicable to a wide variety of ferrites was synthesized from these data. This diagram specifies the schedules of temperature and percent oxygen by which ferrites can be cooled from the sintering temperature without net gain or loss of oxygen.