Enhancing interlaminar fracture toughness of carbon fiber/epoxy resin composite with graphene oxide coated hydroxy iron oxide under magnetic field

To effectively improve the interlaminar toughness of carbon fiber/epoxy resin (CF/EP) composite laminates, toughening nanoparticles (GO@FeOOH) were prepared by electrostatic self-assembly technology, which was the needle-like hydroxy iron oxide coated with graphene oxide. Dispersed in EP matrix and induced by magnetic field, the toughening effect of GO@FeOOH nanoparticles was significantly improved. The modeⅠinterlaminar toughness (GIC) of GO@FeOOH/CF/EP laminates was examined by double cantilever beam test. The effects of GO@FeOOH and magnetic field induction on GIC were investigated. The results show that the GO@FeOOH can significantly enhance the interlaminar properties of CF/EP composite even at a low content of 0.5%(mass fraction), and the initial crack GIC (0.53 kJ·m-2) and crack propagation GIC (0.71 kJ·m-2) of GO@FeOOH/CF/EP are 34.2% and 44.9% higher than those of CF/EP, respectively. On the other hand, the magnetic field induced GO@FeOOH orientation along the magnetic field direction, further signif