Effect of electromagnetic field on slag corrosion resistance of low carbon MgO–C refractories

Using MgO–C refractories containing 6% carbon and the slag with a basicity (CaO/SiO2) of around 0.8, the melting slag resistance experiments of low carbon MgO–C refractories were carried out in induction furnace and resistance furnace, respectively. The microstructure of low carbon MgO–C refractories corroded by slag under the different conditions was analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive spectrometer (EDAX). The results show that in induction furnace having electromagnetic field (EMF), there are MgFe2O4 spinel with a little of Mn ions generated in the interfacial layer. Part of the solid solution is monticellite [CaMgSiO4] containing a little MnO and FeO. While under the condition of EMF free, there is not MgFe2O4 spinel in the interfacial layer and the solid solution is monticellite (CaMgSiO4). At a high temperature, EMF increases the diffusion coefficient of Fe2+/3+ ions, which displaces Mg2+ and forms MgFe2O4 with a little of Mn ions. There are MgAl2O4 spinel in the penetration layers under the conditions of both EMF and EMF free. EMF speeds up corrosion of low carbon MgO–C refractories.