Effect of copper-coated carbon fibre content on microstructure and enhanced properties of carbon fiber reinforced aluminum matrix composites

Carbon fiber reinforced aluminum matrix (CF/Al) composites have great potential for lightweight applications, but their interfacial wettability is poor. In order to improve CF/Al interfacial bonding, a continuous copper coating was deposited on carbon fibers via electroless plating, and the effect of copper-coated carbon fiber (Cu@CF) content on composite microstructure and properties was investigated. The results showed that increasing Cu@CF content decreases density, coefficient of thermal expansion (CTE), and thermal conductivity, while hardness and tensile strength initially increase and then decline. Optimal comprehensive performance was obtained at 1 wt.% Cu@CF, achieving a tensile strength of 281.91 MPa, a friction coefficient of 0.7912, and a wear rate of 2.79 × 10 −2 mm 3 /N·m. Previous studies have primarily focused on enhancing wettability or suppressing interfacial reactions using ZnO, Ni, or Al 2 O 3 coatings, but the influence of coated-CF content has rarely been investigated. By revealing how Cu@CF content regulates Al 2 Cu formation and interfacial compatibility, a clear composition-structure-property relationship is established, providing practical guidance for designing high-performance lightweight Al-based composites.