The densification behaviour and mechanical properties of manganese oxide doped yttria tetragonal zirconia polycrystals (MnO2-doped Y-TZP) were studied. Green samples containing varying amounts of MnO2 (0.05 to 1 wt%) were prepared using the wet colloidal technique. A pressure less sintering technique was used to sinter the specimens at temperatures varying between 1150°C to 1600°C. Sintered bodies were characterized to determine the bulk density, tetragonal content, Young’s Modulus, hardness and fracture toughness. The results showed that the sintered bulk density and Young’s Modulus was enhanced by the addition of up to 0.1 wt% MnO2. On the other hand, fracture toughness of the material was further improved and more prominent for dopant addition of up to 0.3 wt% but for the 0.5 wt% addition of MnO2, an initial decrease in trend was observed, which after a sintering temperature of 1350°C, a drastic increase in properties was observed. As for the hardness of the material, addition of all wt% of dopant exhibited an improvement up to a sintering temperature of 1400°C. In addition to that, hydrothermal ageing - induced phase transformation of Y-TZP sintered at 1300°C for samples containing 0.5 and 1.0 wt% of MnO2 was suppressed.
