Wetting Behavior of Calcium Ferrite Melts on Sintered MgO

Abstract

In contemporary East Asian, high-basicity sinter is the predominant Fe-bearing material used for blast furnace iron making. The wettability of calcium ferrite (CF), which is the main adhesive in high-basic sinter, plays an important role in the assimilation process. In this study, an improved sessile drop technique was used to explore the wettability of a CF-based slag to solid MgO substrate at 1250°C. This investigation entailed adding 2% of Al₂O₃, MgO, SiO₂, or TiO₂. The interfacial microstructure of the slag-substrate and the spreading mechanisms for each system were discussed. The CF-based slag could melt and spread along the substrate. The spreading process was driven by the dissolution of MgO into the slag and the interfacial chemical reaction. The wetting process was divided into four stages. All of the slag systems attained a low apparent contact angle of approximately 3° to 11°, thus indicating that all slag systems could wet well with the substrate. Adding Al₂O₃, SiO₂, or TiO₂ into the CF increases the contact angle.