Phase Equilibria in the System CaO‐MgO‐Iron Oxide at 1500°C

Phase relations in the system CaO‐MgO‐iron oxide were determined at 1500°C at two levels of oxygen pressure, 10 –9 atm and 0.2 atm (air). Particular attention was directed toward de termining the maximum amount of iron oxide which may be tolerated in CaO‐MgO‐iron oxide bodies before a liquid phase forms under equilib rium conditions at the two chosen oxygen pres sures. Inferences are made regarding the possible bearing of the results on the perform ance of tar‐bonded dolomite brick used in steel making furnaces.