Thermodynamic Properties of Nonstoichiometric Yttria‐Stabilized Zirconia at Low Oxygen Pressures

Thermodynamic properties of 8‐mol%‐yttria‐stabilized zirconia have been determined in the 810° to 1040°C temperature range at low Po 2 . A high‐temperature solid‐state coulometric titration method was used. The mass action constant, K ma , can be represented at low Po 2 as K ma =0.677 exp [(–3.98 ±0.03 eV)/kT].