Attention was focussed on the effect of high-temperature heat treatments which were applied before deforming yttria fully-stabilized single crystals. The results showed that the yield stress during constant-strain tests of heat-treated samples was markedly dependent upon the annealing time when the treatment was performed under a very low O-pressure atmosphere. This was explained by analysing the thermodynamics of complex defects which were found at high temperatures, as well as their interaction with mobile dislocations during plastic deformation.

Influence of Defects on the High Temperature Mechanical Behaviour of Yttria Fully-Stabilized Zirconia Single Crystals. D.Gomez-Garcia, A.Gallardo-Lopez, J.Martinez-Fernandez, A.Dominguez-Rodriguez: Radiation Effects and Defects in Solids, 1999, 151[1-4], 895-901