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The effects of adding Al2O3 and CeO2 on the microstructure, mechanical and physical properties of 3 mol% yttria-stabilized zirconia (3Y-TZP) ceramics is presented over a wide sintering regime by pressureless sintering. It has been revealed that small additions of dopant to Y-TZP were beneficial in enhancing the mechanical properties of Y-TZP. Sintered samples were used to evaluate the bulk density, Vickers’s hardness, Young’s modulus, and shrinkage of the material. Al2O3 and CeO2 doped Y-TZPs sintered at 1450∘ C retained high bulk density (>97% of theoretical density) and Young’s modulus (>200 GPa) without sacrificing tetragonal phase stability. The optimum level of dopant was found to be at 0.3 Al2O3 / 0.5 CeO2 at sintering temperature between 1250∘ C and 1450∘C using the standard 12 min holding time cycle, with sintered body exhibiting excellent combination of properties when compared to the undoped ceramics.

The densification behaviour, mechanical properties, and microstructure of high-purity Al2O3 and CeO2-doped Y-TZP with different weight percentage varied from 0.3 to 1 wt% were investigated. The samples were pressed uniaxially at 200 MPa into rectangular bars and discs and pressureless-sintered at temperature ranging between 1250°C and 1450°C for 2 h while the microstructure was characterized with a scanning electron microscope (SEM). Two-step sintering process works well for temperature higher than 1400°C and it created most tetragonal phase arrangement for stable structure to delay ageing through phase transformation. The mechanical properties in terms of bulk density, Young’s modulus, Vickers hardness, and fracture toughness were also measured. The results indicate that the addition of dopants accelerated the densification parameters and reinforced and toughened the obtained bodies. The maximum values for the mechanical properties of the Al2O3 and CeO2-doped Y-TZP ceramics were 6.01, 220 GPa, 13.8 GPa, and 7 MPa for density, Young’s modulus, Vickers hardness, and fracture toughness, respectively, which are higher than those of the doped samples.