Fibre and fibre-surface treatment effects in carbon/aluminium metal matrix composites

Abstract

A systematic study of the relationship between the microstructure of the interface in C/Al composites and its dependence on variations in squeeze-casting parameters has been undertaken. This research has shown that the amount of Al4C3 reaction product at the interface is dependent on the surface structure of the reinforcing fibre and the surface treatment of the fibre. Additionally, the interface shear strength increases with an increase in the amount of reaction product at the interface. An increase in interface shear strength leads to a decrease in composite longitudinal strength. High-resolution electron microscopy and X-ray photoelectron spectroscopy analyses indicate that carbide formation is a conventional two-step process of nucleation and growth. Nucleation occurs preferentially at graphite edge planes on the carbon fibre surface, and growth is restricted along certain matrix planes and directions.