Effect of increase in heterogeneous nucleation sites on the aging behavior of 6061/SiC metal matrix composites

In this study, aging characteristics of an aluminum based metallic matrix reinforced with various volume fraction of silicon carbide was investigated. The results showed an increase in aging kinetics with an increase in volume fraction of SiC particulates. Results of microstructural characterization studies exhibited the presence of solute rich zone in the near vicinity of SiC particulates and the nucleation of secondary phases both at and in near vicinity of SiC particulates. The results of accelerated aging kinetics thus observed were rationalized in terms of an increase in the heterogeneous nucleation volume in the metallic matrix and the constitutional characteristics of the Al/SiC interfacial region.