Mechanical properties of ZrO₂ ceramic stabilized by Y₂O₃ and CeO₂

Abstract

ZrO₂ ceramic was made from evenly dispersed (Y, Ce)-ZrO₂ powder with different compositions, which was prepared by the chemical coprecipitation, and stabilized by compound additions through appropriate techniques. And its mechanical property that is related to the phase content and its microstructure was studied by X-ray diffraction (XRD), scan electron microscope (SEM). The results show that Y₂O₃ has stronger inhibition to the growth of ZrO₂ crystal than CeO₂ has. Therefore, within an appropriate composition range of Y₂O₃ and CeO₂, the higher the content of Y₂O₃, the lower the content of CeO₂, the smaller ZrO₂ crystal. Combining this feature and the stabilization technique with complex additions instead of simple addition, ZrO₂ ceramic with high density and excellent mechanical properties can be made under normal conditions. It is concluded that the improvement of mechanical properties originates from the toughening of microcrack, phase transformation and the effect of grain evulsions.

Keywords

mechanical properties / compound additions / stabilization technique

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