Mechanical properties of alumina/zirconia composites

Fracture toughness, bending strength, Young's modulus, hardness and subcritical crack growth were determined for six different alumina/zirconia composites. The bending strength was modelled using Weibull distribution. The fracture toughness, bending strength and resistance to subcritical crack growth increase as a function of ZrO2 content (stabilized with 3 mol% Y2O3). The authors claim that a threshold stress in a three-parameter Weibull distribution may correspond to a threshold stress intensity factor in which the subcritical crack growth is negligible.