Effect of water vapour on the thermal evolution of the metastable phases of zirconium dioxide

Article abstract of DOI:10.1016/0040-6031(88)87247-2

The role of water vapour on sintering and the tetragonal-to-monoclinic phase transformation of ZrO₂ was studied using different polycrystalline zirconia samples obtained from either thermal decomposition of zirconium nitrate or thermal dehydration of zirconia gels. The samples were heat-treated up to temperatures ranging from 873 to 1173 K in a dynamic vacuum, atmospheric air and a flow of water vapour saturated oxygen. It was found that water vapour accelerates sintering and facilitates conversion of the metastable tetragonal phase into the monoclinic (thermodynamically stable) modification. A metastable cubic phase (a₀ = 510 pm) was also found in some low-temperature ZrO₂ samples.