Thermodynamic Modeling of Equilibrium Subsolidus Phase Relations in the Ag-Pd-O₂ System
From literature values of the thermodynamic activity of Pd in Ag/Pd solid solutions and the Gibbs free energy of formation of PdO as a function of temperature, subsolidus equilibrium phase relations in the Pd-Ag-O2 system have been calculated and compared to results from high-temperature XRD analyses. the developed model takes into account the nonideal activity of Pd in Ag/Pd solid solutions and confirms that increasing the Ag/Pd ratio or decreasing the oxygen activity decreases the temperature at which PdO reduces. It also accurately predicts that the temperature range over which the PdO reduces is broad for Ag-rich compositions, and narrow for Pd-rich compositions.
S. Wang and W. Huebner, "Thermodynamic Modeling of Equilibrium Subsolidus Phase Relations in the Ag-Pd-O₂ System," Journal of the American Ceramic Society, Wiley-Blackwell, Jun 1991.
The definitive version is available at http://dx.doi.org/10.1111/j.1151-2916.1991.tb04110.x
Materials Science and Engineering
Keywords and Phrases
Palladium; Silver; Models; Thermodynamics; Reduction-Oxidation
Article - Journal
© 1991 Wiley-Blackwell, All rights reserved.