Mechanical properties of Al2TiO5 ceramics

Aluminum titanate ceramics (Al2TiO5) is a synthetic ceramic material of potential interest for many structural applications. A critical feature, which greatly limits the mechanical properties of polycrystalline Al2TiO5, is considerable intergranular microcracking, which occurs due to the high thermal anisotropy of individual grains. In this study, the temperature dependencies of mechanical properties were discussed along with the microstructure observation. Both of fracture strength and fracture toughness increased considerably with increasing the temperature. These phenomena were explained on the basis of the stress redistribution and unique microscopic feature on the fracture surface of aluminum titanate ceramics. The experimental results also revealed that the repeated heat treatments resulted in the change of fracture strength and fracture toughness due to the stress redistribution in the Al2TiO5 matrix.