The instability and resulting phase transition of cubic zirconia

The instability of cubic zirconia(c-ZrO2) and the microstructure evolution associated with the cubic-to-tetragonal phase transition are discussed from experimental data together with theoretical approach using computer simula tion. It was found that the electrical repulsive interaction between neighb oring oxygen ions is a parameter to describe the instability of c-ZrO2. Ass uming that this phase transition is of a second-order type, very unique mic rostructures such as the domain structure and the modulated structure, can be simulated by computer. The results are consistent with the microstructur es developed by the diffusionless c-t phase transition and also the diffusi onal phase separation, which were experimentally observed in ZrO2-Y2O3 and the other binary systems containing cubic stabilizing oxides. It is also pr edicted from the simulation that cations such as yttrium ions tend to be se gregated in antiphase domain boundaries (APBs) during annealing in a single t-ZrO2 field. The segregation of yttrium ions in APBs of a single t-ZrO2 w as experimentally detected in the system ZrO2-Y2O3-TiO2. (C) 2001 Elsevier Science B.V. All rights reserved.