Low-temperature Aging of Zirconia Toughened Alumina Under Humid Conditions

摘要

Changes in crystalline phases resulting from low-temperature annealing of different yttria (3 mol%) and ceria (14 mol%) doped PSZ and TTA compositions were investigated under controlled humidity conditions between 150 and 250℃ up to 24 h. It was observed that 70% of the tetragonal phase in 3Y-PSZ had transformed to monoclinic phase while this effect decreased as alumina was added to the system. However, the composition with Al_2O_3 + 15 vol% 3Y-PSZ, which had the best mechanical properties, showed appreciable dependence on hydrothermal treatment. On the contrary, Ce-doped PSZ did not show any aging degradation.