A comparative study of superplastic deformation and cavitation failure in a yttria stabilized zirconia and a zirconia alumina composite

Abstract

A fine grained yttria stabilized zirconia and a zirconia composite containing 20% alumina exhibit superplastic characteristics, with optimum elongations to failure of approx > 500%. There is microstructural evidence for deformation enhanced grain growth and concurrent cavitation in both of these superplastic ceramics. Grain sizes after superplastic deformation may be several times larger than the initial grain size, and the level of cavitation can attain values as high as approx > 30% under some experimental conditions. In a comparative format, some recent experimental results on the microstructural aspects of superplastic deformation and concurrent cavitation in these superplastic ceramics, are presented.