Phase Diagram of CaO-Al2O3-VOx Slag System Under Reducing Atmosphere

The phase diagram information of the CaO-Al2O3-VOx system is of significant importance for the direct alloying study of vanadium (V) during the smelting process of V-containing alloy steel, as well as for subsequent process optimization. This study has utilized the high-temperature phase equilibrium experimental method, combined with scanning electron microscope-energy dispersive spectrometer (SEM-EDS), electron probe micro-analysis (EPMA) and X-ray photoelectron spectroscopy (XPS) detection techniques, to research the phase equilibrium of the CaO-Al2O3-VOx system under argon (Ar) atmosphere at 1400 degrees C. This study reveals that the phase diagram of CaO-Al2O3-VOx system, under the specified conditions, comprises 4 three-phase regions, 7 two-phase regions, and a liquid phase region. This study has plotted the CaO-Al2O3-V2O5-VO2 three-dimensional phase diagram and represented the phase equilibrium in CaO-Al2O3-V2O5, CaO-Al2O3-VO2, CaO-Al2O3-VO2.335, and Ca-Al-V systems. At the same time, the reliability of each projected phase diagram was quantitatively assessed.