Effect of Titania (TiO2) Addition to Zirconia Toughened Alumina (ZTA) Phases, Hardness and Microstructure

Ceramic composites consist of zirconia toughened alumina (ZTA) with TiO2 as additive was fabricated via solid state sintering route. Numerous studies have indicated that TiO2 can be used as sintering additives for Al2O3 and the ability of microstructural control introduce by TIO2. The Vickers hardness of the obtained ZTA-TiO2 was evaluated as a function of different TiO2 addition. Each sample was dry mixed, uniaxially pressed and sintered at 1600 °C for 4 hours in pressureless condition. It is noticed that the presence of TiO2 greatly influence the microstructure of Al2O3. Al2O3 grains tend to increase in size with more addition of TiO2. Characteristics of Vickers hardness increases increases from 1516.13 HV (0 wt% TiO2) to 1615.8 HV (3 wt% TiO2). Addition of TiO2 also increases the bulk density of ZTA-TiO2 from 3.90 g/cm3 (0 wt% TiO2) to 4.10 g/cm3 (3 wt% TiO2).