Dissolution Behavior of AlN in CaO–Al2O3-Based Slag

Fe–Mn–Al–C steelFe-Mn-Al-C steel can form AlNAlN particles because of its high [Al] content (w[Al] = 8–12 wt%), which can affect the properties of slag during continuous casting. In this study, the dissolution behaviorDissolution behavior of AlNAlN in a new CaO–Al2O3-based slagCaO-AlO-based slag without SiO2 was investigated by a static experiment method. Results demonstrated AlNAlN rod could be dissolved in the liquid slag and it only reacted with Li2O, which caused the increase of Al2O3 and the decrease of Li2O in the slag. The interface between slag and AlNAlN was examined by scanning electron microscopy, and the products near the slag side were Al2O3–CaO–BaO–CaF2 complexes, while individual Al2O3 and AlN–Al2O3 complexes were dispersed near AlNAlN side. Additionally, the viscosityViscosity and break temperatureBreak temperature of the slag increased greatly with the increase of AlNAlN. XRD showed the primary crystalline phase in the slag was 11CaO·7Al2O3·CaF2. This work provided theoretical guidance for future application of the slag for high-Al steel.