Influence of internal stresses in superplastic joining of zirconia toughened alumina

Abstract Joints between various compositions of 3 mol% Y 2 O 3 -stabilized ZrO 2 /Al 2 O 3 composites have been produced by superplastic flow at 1350 °C and strain rates of 1×10 −5 s −1 . The joints are pore free and Vickers indentation induced cracks indicate that the joints are strong. The cracks have been used to measure residual stresses, which can be modified by using an interlayer between the materials to be joined. The results agree well with those obtained by finite-element analysis. Ruby fluorescence has been used to measure the hydrostatic stress.