Low-temperature ageing map for 3mol% Y₂O₃-ZrO₂

The ageing behaviour of 3mol% Y₂O₃-ZrO₂ at 100-500° C in a water-containing atmosphere was studied. A critical grain size of ∼ 0.37 μm and a lower temperature limit of ∼80°C for retaining the tetragonal symmetry were deduced from the kinetic study. An "ageing map" constructed on the grain size (G) against ageing temperature (T) plot is proposed to describe the low-temperature ageing behaviour of 3mol% Y₂O₃-ZrO₂.