The reaction between the magnesia–chrome brick and the molten slag of MgO–Al2O3–SiO2–CaO–FetO and the resulting microstructure

The reaction and microstructure at the interface of MgO–Cr2O3 brick and the molten slag of MgO–Al2O3–SiO2–CaO–FetO after static slag corrosion at 1823–1923 K for various times and the resulting microstructure were investigated and characterized. After the static slag corrosion at 1923 K for 4 h, the XRD results show the major phases of periclase MgO, MgCr2O4 spinel, and CaMgSiO4 as the minor phase. MgCr2O4 phase causes MgO to form a discontinuous phase in MgO–Cr2O4 brick. After static slag corrosion at 1923 K for 4 h, SEM micrographs show that brick interior cracks, MgO and dissolved MgO. MgO dissolved due to the molten plag penetrated into the brick interior and reaction with it, leading to a localized dissolution of brick slag. TEM micrographs and ED patterns demonstrate that the minor phase of (Mg, Fe)(Al, Cr)2O4 precipitates in the MgCr2O4 matrix.