The interaction between Fe ₂ O ₃ ‐bearing molten slag and MgO‐C refractory containing calcium magnesium aluminate antioxidant

Abstract The interaction behavior between iron oxide‐bearing slags and carbon‐bonded MgO refractory (MgO‐C) containing calcium magnesium aluminate (CMA) was investigated at 1400°C, 1500°C, and 1600°C. After the iron oxide was reduced by the carbon from the MgO‐C refractory, a significant amount of MgO and metallic iron was observed to precipitate and disperse in the bulk of slag. During the iron oxide reduction process, the penetrative ability varied throughout the whole process, attributed to the effect of iron oxide on the thermophysical properties of the molten slag. No reduced iron was detected on the side of MgO‐C, which implies the slag penetration was primarily conducted after the iron oxide was reduced in the slag. Spinel was found to be predominantly formed during the interaction between MgO‐C refractory bearing CMA additive and slags, which strongly hindered further refractory corrosion. Additionally, the Ca 3 Al 4 MgO 10 phase is predicted via ThermoCalc and XRD.