Study of the Structure and Mechanical Properties of PSZ (Partially Stabilized Zirconia) after Heat Treatment at 1600 ˚C

Abstract

The phase composition and twin structure of PSZ crystals after heat treatment at 1600 ˚C have been studied in relation to the content of the stabilizing impurity (Y2O3) by X-ray diffraction and transmission electron microscopy. The measurement of both hardness and fracture toughness by microindentation has been carried out. Studies have shown that crystals of PSZ obtained by directional solidification of the melt consist of two tetragonal phases (t and t’), with varying degrees of tetragonality. The yttrium-enriched phase t’ is ‘‘untransformable’’ in contrast to the t phase, with a lower content of yttrium, which, under the influence of mechanical stress, undergoes a martensitic transition to the monoclinic form. Increasing the stabilizing impurity concentration leads to an increase in the volume fraction of the ‘‘untransformable’’ phase. Increasing the concentration of Y2O3 also affects the form and dispersion of the twin domains. In this work it is shown that the quantity of hardening (fracture toughness) is proportional to the content of the transformable t phase. This work was supported by grants from the company "OPTEC" When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35406