MASS-SPECTROMETRIC STUDY OF THE VAPORIZATION OF MAGNESIUM OXIDE FROM MAGNESIUM ALUMINATE SPINEL.

Abstract

The partial vapor pressures of Mg(g) over the spinel solid solution system, MgO multiplied by (times) nAl//2O//3(n equals 1. 0, 2. 0, and 2. 8), have been measured by the mass-spectrometric Knudsen-cell method. In the temperature range from 1850 to 2300 K, the pressures are described by the various equations that are presented. The observed values were discussed in comparison with the calculated ones obtained by an approximate thermodynamic treatment of an ionic solid solution with composition-dependent vacancies.