Quasi-static compression characterization of binary nanoclay/graphene reinforced carbon/epoxy composites subjected to seawater conditioning

Fiber reinforced polymer composite (FRPC) materials are superior to other conventional materials because of their high strength to weight ratio, corrosion resistance, and moisture resistance. FRPC materials are preferred in many high-end applications such as marine, automobile, aerospace, and advanced sporting goods. The aim of this study was to investigate the in-plane quasi-static compressive and durability studies of nanophased FRPC materials. Composite samples were fabricated using unmodified epoxy and epoxy modified with montmorillonite nanoclay (MMT), graphene nanoplatelets (GNP), and a combination of the two as a binary reinforcement with carbon fibers. Quasi-static compression tests were conducted for mechanical property evaluation. Seawater conditioning was performed for a six-month period both at room and arctic cold temperatures. The results indicated that addition of GNP and MMT improved the compressive properties of carbon/epoxy composites compared to unmodified carbon samples. Specific compressive strength and modulus of GNP infused samples improved by 30 and 41% respectively; the samples showed a relatively higher strain to failure than the unmodified samples. Specific compressive strength and modulus increased by 32 and 47%, respectively, for carbon/epoxy samples with MMT reinforcement. Performance of hybrid carbon/glass/epoxy composites was lower compared to other FRPC materials considered in the study. The mode of failure of fractured samples investigated using scanning electron microscopy (SEM) showed a rough morphology after incorporation of nanoparticles into the polymer matrix. This is indicative of enhanced interfacial bonding between carbon/epoxy and the nanoparticles.