On the low‐velocity and high‐velocity impact behaviors of aramid fiber/epoxy composites containing modified‐graphene oxide

Abstract This work evaluates the effects of modified‐graphene oxide ( M ‐GNs) loading and graphene nanoplatelets (GNs) modification on the low‐velocity and high‐velocity impact (LVI and HVI) behaviors of aramid fiber/epoxy composites. Aminopropyltrimetoxysilane compound was used to modify the surface of the GNs. The epoxy resin was incorporated with 0.1, 0.3, and 0.5 wt% M ‐GNs to fabricate the multiscale M ‐GNs/aramid fiber/epoxy composites via the hand lay‐up route. The obtained results from the LVI and HVI tests revealed that the highest impact resistance was related to the multiscale specimen having 0.3 wt% M ‐GNs. For example, under LVI conditions (impact energy of 60 J), the addition of 0.3 wt% M ‐GNs enhanced the force peak and absorbed energy of the composite by 44% and 95%, respectively. The addition of 0.3 wt% M ‐GNs increased the ballistic limit and absorbed energy of the composite (exposed to the HVI) by 23% and 52%, respectively. The fracture surface of the specimens was evaluated by scanning electron microscopy to find the dominant mechanisms. It was also found that the incorporation of the M ‐GNs reduced the damaged area and enhanced damage tolerance. The results demonstrated that modification of the GNs enhanced the LVI and HVI properties of the multiscale composites.