Mechanical and damping properties of graphene-reinforced CuAlMn matrix laminated composites

Graphene (GR)/Cu-11.9Al-2.5Mn composites with bionic laminar structure were prepared by vacuum hot pressing method using flake metallurgy, and the effects of graphene content on the microstructure, mechanical properties and damping properties of the composites were investigated. The results showed that the addition of 0.25 wt% graphene increased the tensile strength and hardness by about 17% and 27%, respectively, which was attributed to the effective load-transferring mechanism of the graphene uniformly dispersed in the matrix, and the increase in the dislocation density caused by thermal expansion mismatch also affected the mechanical properties. Meanwhile the damping properties of 0.25 wt% graphene samples were significantly improved, which was attributed to the introduction of the enormous dislocations and micro interfaces by the addition of graphene, and a significant amount of energy was dissipated by the dislocation motion, GR/matrix interfacial sliding, and frictional sliding between the graphene layers. Therefore, it can be concluded that both mechanical and damping properties enhancement mechanisms are related to dislocation behavior and interfacial bonding, and the addition of an appropriate amount of graphene can achieve a balance between mechanical and damping properties.