Strength, fracture toughness and Vickers hardness of CeO2-stabilized tetragonal ZrO2 polycrystals (Ce-TZP)

Dense Ce-TZP ceramics containing about 7 to 16 mol% CeO2 were fabricated using fine powders prepared by the hydrolysis technique. The mechanical properties of these ceramics were evaluated. The bending strength of sintered bodies with 10 to 12 mol% CeO2 content and small grain-size was about 800 MPa. Fracture toughness was measured by two different methods; a micro-indentation technique and the chevron notched beam technique. A high fracture toughness was obtained for sintered bodies with 7 to 10% CeO2 content and large grain-size. Fracture toughness and hardness were dependent on CeO2 content and grain-size. These mechanical properties are discussed on the basis of the stability of the metastable tetragonal phase depending on CeO2 content and grain-size.