LAUSR

Pure aluminum and AC8A aluminum alloy matrix composites, which were reinforced with PANand pitch-based short carbon bers, were fabricated by squeeze casting, then the composites were exposed to a heat treatment. The effects of the ber types, composition of the matrix, and heat treatment on the mechanical properties of the composites were investigated. The bers were in a random planar arrangement in the composites. Although the aluminum carbide was formed due to the reaction between the PAN-based ber and pure aluminum during the casting process, there was no reaction products near the PAN-AC8A, pitch-pure aluminum and pitch-AC8A interfaces. Although the ultimate compressive strength of the PAN-based ber composite was greater than that of the pitch-based ber composite under every condition, the strength of the PAN-based ber composite degraded due to the heat treatment when pure aluminum was used as the matrix. Examination of fracture surface indicated that the lower reinforcing effect of the pitch-based ber would be due to delamination at the boundary between the highly-developed graphite crystallites in the ber. A hardness measurement of the bers in the composites using a nano-indenter revealed that the interfacial bonding strength between the pure aluminum and PAN-based ber degraded due to the heat treatment. [doi:10.2320/matertrans.M2017023]