An experimental investigation on the low-velocity impact performance of the CFRP filled with nanoclay

Abstract

In this study, the effect of the commercial nanoclay Cloisite® 20A on the impact response of the carbon fiber reinforced polymers was investigated using a low-velocity drop-weight impact machine under three impact energy levels of 10 J, 15 J, and 20 J. Contrary to other studies and for more improvement of the properties, clay nanoparticles were dispersed in the resin through solution blending methodology, and laminate samples were fabricated by vacuum infusion process. The optimal percentage of nanoclay was determined by tensile and flexural tests on the epoxy samples containing various nanoclay contents (0.2-0.8 wt.%). For a deeper understanding of the damaged nanocomposites, force-time, force-displacement, and energy-time responses were analyzed. Finally, the influence of nanoclay incorporation by solution blending method and the impact-induced damages were explored by measuring the permanent indentation, radiographic analysis, optical and field emission scanning electron microscopy. Addition of 0.2 wt.% Cloisite® 20A led to a significant increase in the maximum impact force (up to 25.7%), a reduction of the absorbed energy (up to −50.25%), and a decrease in the maximum displacement (up to −29.08%). Moreover, the permanent indentation and the delamination area were significantly decremented compared to the other studies using direct dispersion to disperse nanoclay in the resin matrix. Furthermore, it was revealed that the addition of nanoclay resulted in the transition of the failure mode of carbon fiber reinforced polymer during low-velocity impact from delamination to matrix cracking.