High Temperature Mass Spectrometric Study of Thermodynamic Properties and Vaporization Processes of Oxide Systems: Experiment and Modeling

Abstract

The unique opportunities and features of high temperature mass spectrometric method for study vaporization processes and thermodynamic properties of oxide systems and materials (glasses, ceramics and coatings) were considered. Various types of vapour species were found over oxide systems studied such as the associated, dissociated and polymerized products of vaporization. The regularities of the vaporization of the binary and multicomponent oxide systems according to the position of oxide modifier in the Periodic table of atoms were illustrated and discussed from the point of view of the acid-base concept. Results on determination of thermodynamic functions in oxide systems were considered taking into account the main requirements for the confirmation of their reliability. Thermodynamic functions of oxide systems studied showed various signs of the deviations from the ideality. The general lattice theory of associated solutions was used for the calculation of thermodynamic properties of the ternary silicate melts studied. Based on this theory the correlation between thermodynamic functions obtained in the systems under consideration and the number of various types of bonds formed in these melts was illustrated. Using this approach the different levels of deviations from the ideality in the melts studied were clarified. Examples of the practical applications of high temperature mass spectrometry for developing advanced materials were shown.