Processing and characterisation of 3-3 Al alloy/Al2O3 interpenetrating composites (IPCs)

Aluminium alloys, reinforced with ceramic particles or fibres, are desired materials in high performance applications due to their superior properties. Amongst aluminium matrix composites, interpenetrating composites, with both the matrix and reinforcement three dimensional throughout the microstructure, are more promising in providing truly multi-functional properties. However, due to the poor wetting between most metals and ceramics, pressure is normally needed in processing. In this research, a pressureless infiltration technique was adopted, which has the advantage of offering complex shape capability, no risk of damaging the ceramic skeleton and is potentially cost-effective and suitable for commercialization. The aims were to produce Al alloy/Al2O3 interpenetrating composites using the pressureless infiltration technique; to optimize the processing for full infiltration; to understand the infiltration mechanism and to characterise the composites in terms of both their microstructure and mechanical properties. [Continues.]