Effect of liquid-forming additives on the sintering and mechanical properties of Al2O3/3Y-TZP (30 vol.%) composite

Al2O3/3Y-TZP (30 vol.%) composite was pressurelessly sintered with addition of TiO2MnO2 and/or CaOAl2O3SiO2 glass. It was found that TiO2MnO2 addition greatly enhanced the densification of the composite by the formation of a low-viscosity liquid at sintering temperature. In contrast, the high-viscosity liquid formed by CaOAl2O3SiO2 glass improved mechanical properties because of its repressing effect on grain growth. The composite could be obtained at a temperature as low as 1400°C by co-doping with TiO2MnO2 and CAS glass. Bending strength of 552±64 MPa and fracture toughness of 6.03±0.22 MPa m1/2 were obtained with a doping level of 2 wt.% TiO2MnO2 and 2 wt.% CAS glass.