Mass-spectrometric investigation of evaporation of solid solution components in the system of zirconium and praseodymium oxides

The results of the investigations of the evaporation processes for the ZrOsub(2)-Prsub(2)Osub(3.67) solid solution components, with Prsub(2)Osub(3.67) contained at 55 and 65 mol.%, and for pure Pr2O3 and Prsub(2)Osub(3.67) by the Knudsen effusion method with the mass-spectrometric analysis of the gas phase are given. Prsub(2)Osub(3.67) was found to rapidly loose oxygen at heating in vacuum; this is accompanied by decreased partial pressures of PrO (gas), PrO2 (gas) and O(gas), while the condensed phase approached Pr2O3xPr2O3 in its composition and displayed a virtually congruent manner of evaporation. The partial PrO (gas) pressure above the solid solutions ZrOsub(2)-Prsub(2)Osub(3.67) is directly proportional to the mole fraction of the second component within the error ranges