A REACTION MODEL TO SIMULATE COMPOSITION CHANGE OF MOLD FLUX DURING CONTINUOUS CASTING OF HIGH Al STEEL

In order to find countermeasures against degradation of mold flux properties in high Al steel continuous casting, it is important to understand the reaction between Al-containing steel and CaO-SiO2-based molten flux. In the present authors' research group, the reaction rate and mechanism governing the reaction have been experimentally investigated. Based on those observed mechanism, a slag-metal reaction model was developed in order to interpret the reaction and to predict similar reactions between high Al steel and mold flux used for continuous casting process. The model considers both thermodynamic and kinetic information, as well as rate-controlling step observed in the authors' previous investigation. Thermodynamic information for chemical reaction was interpreted by ChemApp coupled with FactSage thermodynamic database. This is connected to mass flux equations for all relevant components in the system. Flux viscosity change and its effect on the mass flux are also taken into account. The reaction model developed in the present study showed good reproduction of the experimental data. Some possible applications are also shown.