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Abstract

A study involving manufacturing and tensile testing was conducted to elucidate the mechanical properties of a SiC fibre reinforced aluminum. Areas analyzed included production methods, failure mechanisms, tensile behaviour and interfacial bonding. A well dispersed fibre distribution in the as cast composite was difficult to obtain. This arises from the high degree of intermingling of fibres in the as-received tows. The poor distribution can lead to incomplete fibre utilization and increase composite susceptibility to delamination damage. The strength of the composites tested were below that expected from a rule of mixtures (ROM) value. Fibre damage incurred during manufacturing and by the formation of aluminum carbide on the fibre surface are possible causes for this anomaly. Also, fibre/(matrix plastic deformation) interaction can lead to premature composite failure especially at the low volume fractions of fibres being analyzed. On a microscopic level good bonding between the fibre and matrix was observed. This adhesion was attributed to the formation of aluminum carbide at the fibre/matrix interface. Synergistic strengthening of the matrix was observed for several tensile samples. This phenomena may be attributed to fibre distribution altering the aluminum matrix deformation behaviour.