Optimizing Mechanical and Biotribological Properties of Carbon Fiber/Epoxy Composites by Applying Interconnected Graphene Interface

Interface is critical for the short-term and long-term performance of carbon fiber-epoxy-hydroxyapatite (CHE) composites for orthopedic implant applications because the stress transfer from the matrix to the fibers is via the interface. Herein, a novel type of interconnected graphene (IGE) nanointerface was fabricated in CHE by chemical vapor deposition method with a porous and radially aligned structure being achieved. Effects of IGE on morphology and microstructure of hydroxyapatite coating, mechanical and biotribological properties of CHE were investigated. The results show that IGE could induce the uniform formation of hydroxyapatite, favor the infiltration of epoxy, and promote the bonding of the fiber/matrix interface and the cohesion strength of epoxy matrix, thus enhancing the mechanical and biotribological properties of CHE. Compared with CHE, the tensile strength of IGE modified CHE increased by 21.9 %, and the wear rate of IGE modified CHE decreased by 93.4 %. This work demonstrated the potential of IGE as an interface for mechanically-strong and wear-resistance CHE. IGE-CHE possessing excellent mechanical and biotribological properties has potential application for bone replacement and bone fracture plate.