Influence of high temperature holding on tensile strength of PAN-based carbon fiber reinforced aluminum–magnesium alloy composites fabricated by ultrasonic infiltration method

Abstract

Carbon fiber reinforced aluminum alloy composites (CF/Al composites) are expected to be applied to electric power cable due to superior specific strength and specific modulus. But it is reported that CF/Al composites form aluminum carbide (Al4C3) at the interface between carbon fiber and aluminum alloy. However, influence of operating temperature, in usual 300°C, on the growth of Al4C3 and tensile strength of CF/Al composites have not been clarified. In this study, at first, PAN-based CF (M40J) /Al composites are fabricated with ultrasonic infiltration method and hold at 300, 450, 500°C for 64 h. Secondary, influence of holding temperature on the quantity of Al4C3 was investigated. Thirdly, relationship between the quantity of Al4C3 and tensile strength of CF/Al composites was examined. As holding temperature increased, the quantity of Al4C3 increased and tensile strength decreased. By examining extracted fiber with SEM, it was found that tensile strength should be decreased because Al4C3 corroded carbon fiber. Kinetics calculation indicated that remaining strength of the CF/Al composites, held at 300°C for 36 years, was nought. As a result, it will be difficult to apply the CF/Al composites to electric power cable.