Structure and mechanical properties of crystals of partially stabilized zirconia after thermal treatment

• Published in: Physics of the solid state 2013-08, Vol.55 (8), p.1690-1696
• Main Authors: Borik, M. A., Bublik, V. T., Kulebyakin, A. V., Lomonova, E. E., Milovich, F. O., Myzina, V. A., Osiko, V. V., Seryakov, S. V., Tabachkova, N. Yu
• Format: Article
• Language: English
• Subjects: Analysis; Hardness; Mechanical Properties; Physics; Physics and Astronomy; Physics of Strength; Plasticity; Solid State Physics; Zirconium; Zirconium oxide
• ISSN: 1063-7834; 1090-6460
• DOI: 10.1134/S1063783413080052

The phase composition and morphology of the twin structure of the Y 2 O 3 -stabilized zirconia crystals (from 2.8 to 4.0 mol %) after the thermal treatment at 1600°C have been investigated by X-ray diffractometry and transmission electron microscopy. It is shown that as the concentration of the stabilizing Y 2 O 3 impurity increases, the character of the twin structure changes, and the amount of the untransformed phase t ′ increases. The dependence of the hardness and crack resistance of the crystals of partially stabilized zirconia on the Y 2 O 3 concentration and the indenter orientation is investigated using the microindentation method. The sample with the lowest concentration of the stabilizing Y 2 O 3 impurity turned out the most crack resistant. This can be explained by a high content of tetragonal phase t in it, which provides the transformation strengthening mechanism of the material, and by a more multilevel character of twinning.