Interfacial structure characterization of C/Al composites

The interfacial reaction product Al{sub 4}C{sub 3} in C/Al composites was shown to nucleate preferentially on the graphite surface where contaminants or structural defects existed. Crystallographic relationships between Al{sub 4}C{sub 3} and graphite or aluminum matrix are reported. The morphology of Al{sub 4}C{sub 3} was found to be controlled by processing conditions, which is interpreted in terms of the extent and nature of two different growth mechanisms. Concentration gradients of carbon in aluminum matrix was found within the distance of 300mn to carbon fiber surface. The carbon atoms for the growth of Al{sub 4}C{sub 3} are considered to be supplied through the aluminum matrix along this concentration gradient.