CYCLIC FATIGUE CRACK GROWTH RESISTANCE OF Al_20_3-Al_2TiO_5 COMPOSITES

摘要

The role of the aluminium titanate and the grain size of alumina in the flaw tolerance of Al_20_3-Al_2TiO_5 composites has been studied. The fabrication of these in situ formed composites with different grain sizes of alumina with homogeneous and heterogeneous microstructure, is described. An investigation was carried out regarding whether a correlation exists between the cyclic fatigue crack growth behaviour in composites with different distribution and quantity of aluminium titanate and different average grain size of the alumina matrix, and the magnitude of the bridging forces developed when the cracks propagate at similar rates.