R-curve behaviour of 9Ce-TZP zirconia ceramics

Stabilised zirconia ceramics may undergo a stress-induced tetragonal-to-monoclinic phase transformation. At crack tips, a transformation zone with compressive stresses develops, leading to an increase in fracture toughness, which depends on the size and geometry of the transformation zone. The influence of grain size on the R-curve behaviour and transformation zone size is investigated for five 9Ce-TZP zirconia ceramic materials of variable grain size.