Laboratory scale study of uncommon degradation SiO2 refractories used on induction furnaces

The refractory degradation on induction furnace walls at different points was studied. A SiO2 (98.8%) base refractory was analyzed with two different slag chemical composition through crucible and dipping laboratory degradation test and also applying an asymmetric modeling. The slag, refractory structure and slag penetration was analyzed by optical microscopy using reflecting light technique. The results demonstrated that slag penetration starts on the refracto-ry pores produced by the sintering process and also by hollows generated by the came off grains. The modeling results evidenced that, with high frequency (240 Hz), a high Lorentz force (14.26 N) is originated but with a low liquid velocity (6 m/s) that have a perpendicular vector direction to the furnace walls, making pressure over the filtered slag.