Effect of graphene nanoplatelets on water absorption and impact resistance of fibre-metal laminates under varying environmental conditions

Abstract This work investigated the effect of graphene nanoplatelets (GNPs) on the water absorption and impact resistance of fibre-reinforced metal laminates (FMLs) under hygrothermal and salt spray environments. Containing GNPs of 0.1, 0.3, 0.5 and 1.0 wt%, the resulting nanocomposite FMLs were investigated for 28 days of aging in the environments. The salt-spray environment was found to pose a more serious effect on FMLs than the hygrothermal environment. The addition of GNPs at 0.3 wt% effectively reduced the water absorption of FMLs by 57.6% whilst improving their impact resistance by 150.6% in comparison with pure FML in the case of treatment by the salt-spray environment. The water absorption reduction is caused by GNPs creating a tortuous path for diffusion of water molecules and restricting the intermolecular motion of the epoxy molecules. The impact resistance improvement can be attributed to GNPs improving the modulus and crack-resistance of the epoxy matrix and thus the interfacial bonding of FMLs.