Enhanced Fracture Toughness in Layered Microcomposites of Ce‐ZrO ₂ and Al ₂ O ₃

Abstract

Laminar composites, containing layers of Ce‐ZrO 2 and either Al 2 O 3 or a mixture of Al 2 O 3 and Ce‐ZrO 2 , have been fabricated using a colloidal method that allowed formation of layers with thicknesses as small as 10 μm. Strong interactions between these layers and the martensitic transformation zones surrounding cracks and indentations have been observed. In both cases, the transformation zones spread along the region adjacent to the layer, resulting in an increased fracture toughness. The enhanced fracture toughness was observed for cracks growing parallel to the layers as well as for those that were oriented normal to the layers.