Role of concurrent cavitation in the fracture of a superplastic zirconia-alumina composite

Superplastic zirconia-alumina composites exhibit very large elongations to failure of ≥ 500% under optimum conditions. A quantitative microstructural study reveals that the composite is susceptible to considerable internal cavitation, with the level of cavitation increasing with increasing strain rate. The observed inverse relationship between the level of cavitation and the elongation to failure suggests strongly that the tensile ductility is limited by the evolution of cavitation damage during superplastic deformation