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The processing of yttria-stabilised zirconia (Y-ZrO2)-based ceramic nanocomposites by means of pulsed electric current sintering (PECS) is described. A nanometer-sized electrically conductive secondary TiCN phase was added to the insulating zirconia matrix in order to make the composite electrically conductive. The paper focuses on the importance of processing conditions and highlights the benefits of the PECS method as compared to more traditional hot pressing. The mechanical and microstructural properties of the ZrO2–TiCN composites have been determined, and the benefits of using an electrical current to densify these composites were explained in terms of the evolution of the electrical properties of the densifying powder compact. [ABSTRACT FROM AUTHOR]

3Y-TZP/Al2O3 composites were pressureless sintered with the addition of TiO2-MnO2 and CaO-Al2O3-SiO2 glass. The densification, microstructure and mechanical properties of the composites were investigated. It was found that the composites could be densified at a temperature as low as 1400^°C by liquid phase sintering. The majority of the grain sizes for both Al2O3 and ZrO2 were below 1 µ m because of the lower sintering temperature. A bending strength of 934 ± 28 MPa and fracture toughness of 7.82 ± 0.19 MPam1/2 were obtained for 3Y-TZP/Al2O3 (20 vol%) composite. Transformation toughening is considered the responsible toughening mechanism. [ABSTRACT FROM AUTHOR]