Superplastic joining of alumina and zirconia ceramics

Al2O3/ZrO2 composites with from 0 to 100% ZrO2 content were bonded by superplasic flow at 1280, 1350 and 1400 °C under the pressure 30 or 50 MPa during the time from several min to several hours. FGM joints between Al2O3 and ZrO2 parts and joints between non-superplastic coarse grained alumina bars with aid of thin superplastic plates were also obtained. All the joints were pore-free and strong. For Δα > 1 × 10−6 °C−1 cracks parallel to interface arose near the joint. Residual stress distribution was evaluated by finite-element and Vickers indentation analysis. The calculations revealed that critical tensile stresses appeared only in perpendicular direction to the interface.