Multiscale graphene/carbon fiber reinforced copper matrix hybrid composites: Microstructure and properties

Multiscale graphene/carbon fiber (G/CF) reinforcements were developed for copper matrix hybrid composites. The homegenious G/CF/Cu mixture powders were firstly prepared by the simple wet-mixing process, and then densified by hot-pressed sintering to obtain bulk composites. Microstructure, electrical conductivity and mechanical properties of such composites were investigated. In the sintered compacts, the hybrid G and CF reinforcements distributed randomly in Cu matrix. CF presented the various space orientations, and G nanosheets exhibited the interconnected network distribution. Hardness and tensile yield strength of composites were improved evidently by hybrid G/CF addition, which increased with G increasing. However, the ultimate tensile strength were firstly enhanced and then deteriorated by increasing G content. The lower electrical conductivity showed in the more G-added composite, but still reached more than 80.0% IACS. These performance change could be sought in the spatially geometrical distribution and characteristic of hybrid CF/G additions, and the relevant mechanisms were discussed.