ABSTRACT
Effects of Al2O3 addition made as either fine Al2O3 particles or Al2O3 platelets on the room temperature mechanical properties of Y-TZP were studied in composites of Al2O3/3Y-TZP, which were hot-isostatically pressed. Alumina additions to the 3Y-TZP matrix, irrespective of particulate morphology, result in an increase in fracture toughness. In situ crack propagation studies have shown that Y-TZP and Al2O3/Y-TZP composites are strongly susceptible to subcritical crack growth. An R-curve in the Al2O3/Y-TZP composite was obtained with the crack resistance rising by 2 MPa.m1/2 during 80–120 μm crack extension.
