Influence of interfacial chemical reaction for tensile strength of carbon fiber reinforced aluminum-magnesium alloy composites fabricated by ultrasonic infiltration method

Abstract

Carbon fiber reinforced aluminum alloy composites (CF/Al composites) are expected in aerospace and electric power cable industries due to superior specific strength and specific modulus. But, it is known that CF/Al composites form aluminum carbide (Al4C3) at the interface between carbon fiber and aluminum alloy when CF/Al composites are fabricated. However, effects of type of carbon fiber (PAN, pitch) on growth mechanism of Al4C3 and tensile strength of CF/Al composites have not been clarified. In this study, at first, CF/Al composites are fabricated with ultrasonic infiltration method. Secondary, effects of type of carbon fiber and fabricating time on quantity and size of Al4C3 were investigated. Thirdly, effects of quantity and size of Al4C3 on tensile strength of CF/Al composites were examined. The length of Al4C3 increased with increase in fabricating time for PAN-based composites. It was suggested that the numbers of nucleating sites of Al4C3 increased with an increase in fabricating time for pitch-based composites. As the result, as to the PAN-based composites, it should be controlled less than 100 nm of the length of Al4C3 to inhibit degradation of tensile strength. As to the pitch-based composites, fabricating time should be shorter.