SPALLING IN ZIRCONIA-REINFORCED CERAMICS

Analysis of spalling cracks in zirconia-reinforced ceramics shows that the presence of dilatantly transforming particles can give rise to si gnificant strengthening, even for cracks that are close to the surface with respect to the height of the transformed region. The inherently mixed-mode loading on the crack tip results in an asymmetrical zone sh ape and makes toughening-strengthening phenomena more sensitive to mat erial parameters than the usually studied symmetrical loading configur ations.