Thermodynamic description of the interaction processes in the Cu–Ce–O system in the temperature range 1100–1300°C

Resumo

A thermodynamic simulation and an experimental study of the interaction between cerium and oxygen in liquid copper have been performed. The thermodynamic analysis of the interaction processes in the Cu–Ce–O system is carried out using the technique of constructing the surface of solubility of components in a metal in the temperature range 1100–1300°C. As a result of simulation, data on changes in the Gibbs energy ΔG_T° and the equilibrium constants of formation of cerium oxides Ce₂O₃ and CeO₂ from the components of a copper-based metallic melt are obtained. The first-order interaction parameters (according to Wagner) of cerium and oxygen dissolved in liquid copper, namely, e_Ce^Ce, e_O^Ce, and e_Ce^O, are evaluated. Experimental studies of the Cu–Ce–O system have been performed. The morphological features, the size, and the composition of nonmetallic inclusions formed as a result of interaction in the Cu–Ce–O system are studied using scanning electron microscopy and electron-probe microanalysis.