Effect of component variation in CaO–SiO 2 –MgO–Al 2 O 3 slags on controlling corrosion of olivine based disposable tundish lining material

This study concerns the chemical reactions involved and the phases formed during penetration of slags of variable compositions into porous tundish disposable lining material. The liner is mainly composed of a mixture of MgO and olivine with an organic binder. Slags of different compositions were formulated and indicated a variable composition of CaO (12–20%), SiO₂ (44–55%), Al₂O₃ (4–16%), MgO (10–20%), MnO (9–12%) and FeO (2–3%). Experimental work indicated that when slag penetrated into pores of the refractory, the porosity was reduced depending on the penetration depth. It was observed that the lower the melting point of the slag, the higher the depth of slag penetration by capillary action. The phases of forsterite (Mg₂SiO₄), magnesiowustite (MgO.FeO) and monticellite (CaO.MgO.SiO₂) were formed in the bulk refractory by the slag, and the chief component of the refractory responsible for the formation of those phases is the periclase.