High Strain Rate Behavior of Epoxy Graphene Oxide Nanocomposites

The present work investigates the novel impact loading response of two-dimensional graphene oxide (GO) reinforced epoxy nanocomposites at high strain rate. The testing was performed up to 1000 s(-1) of high strain rate, where maximum damage occurs during the impact loading conditions. The Split Hopkinson Pressure Bar (SHPB) was used for the impact loading of the composite specimen. The nanofiller material GO was synthesized by chemical oxidation of graphite flakes used as the precurser. Synthesized GO was characterized using FTIR, UV-visible, XRD, Raman Spectroscopy and FE-SEM. Solution mixing method was used to fabricate the nanocomposite samples having uniform dispersion of GO as confirmed from the SEM images. Strain gauges mounted on the SHPB showed regular signal of transmitted wave during high strain rate testing on SHPB, confirming the regular dispersion of both the phases. Results of the transmission signal showed that the solution mixing method was effective in the synthesis of almost defect-free nanocomposite samples. The strength of the nanocomposite improved significantly using 0.5 wt.% reinforcement of GO in the epoxy matrix at high strain rate loading. The epoxy GO nanocomposite showed a 41% improvement in maximum stress at 815 s(-1) strain rate loading.