Thermodynamics of the Al–C–O Ternary System

Abstract

A critical analysis of vapor pressure determinations over the ternary system, i.e., mainly the pseudobinary section , is performed in order to further explain the behavior of alumina in the presence of carbon (in contact or not) in vacuum furnace environments. The vapor pressure studies allow the determination of standard enthalpies of formation of the oxycarbides, mainly for . Values as retained are compared with those used in phase diagram and thermodynamic data optimizations. The determination of thermodynamic data for the other oxycarbide is not possible in the context of vapor pressure measurements because nonequilibrium vaporization occurs in concordance with metastable phases.