Reaction between Magnesia–Chrome Brick/Slag Interface by Electric Furnace Static Slag Corrosion Test

Abstract

Reaction of magnesia-chrome (MgO-Cr₂O₃) brick with molten MgO-Al₂O₃-SiO₂-CaO-Fe_tO slag using electric furnace static corrosion test method was investigated by X-ray diffraction (XRD), optical polarized microscopy (OPM), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), scanning transmission electron microscopy (STEM) and electron diffraction (ED). From XRD patterns it is found that the crystalline phases at slag-refractory interface are mostly MgO and MgCr₂O₄ with a minor phase of CaMgSiO₄. The MgO content in MgO-Cr₂O₃ bricks decreases with temperature increasing. The activity coefficient of MgO (γ_MgO) in the molten MgO-Al₂O₃-SiO₂-CaO-Fe_tO slag also increases with temperature increasing. The diffusion layer of (Mg,Fe) (Cr,Al)₂O₄ is formed between slag area and MgCr₂O₄ matrix.