Mechanical, Thermal and Morphological Characterization of Graphene/Al2O3-Reinforced Epoxy Hybrid Nanocomposites

Abstract

This work investigates the hybrid nanocomposites manufactured by direct mixing by dispersing varying weight percentages (wt.%) of graphene nanoparticles (GNPs) and Al₂O₃ NPs in epoxy resin. Their properties are then obtained using various mechanical (tensile, flexural, impact, and hardness) and thermal (thermogravimetric) analyses. Furthermore, their microstructure and functional groups are studied by SEM and FTIR, respectively. The hybrid nanocomposite, which contains 1.5 wt.% GNPs and 8.5 wt.% Al₂O₃ NPs, has excellent mechanical properties. Compared to a composite without GNPs, the tensile strength, flexural strength, impact strength, and shore D hardness improve by 95.12, 90.01, 171.43, and 19.75%, respectively. It is also found that hybrid nanocomposite exhibits enhanced thermal stability as GNPs increase, particularly at lower wt.% of Al₂O₃. The SEM of tensile fractured specimens of GNPs/Al₂O₃ epoxy hybrid nanocomposites reveals prominent failure mechanisms, including agglomeration of GNPs and debonding between the GNPs/Al₂O₃ and epoxy. The FTIR spectroscopy analysis reveals distinctive spectral peaks indicating successful incorporation of Al₂O₃ and GNPs into the epoxy-based composite, with observed peaks corresponding to functional groups and bonds characteristic of each component. These findings suggest that the manufactured nanocomposite holds promise as a component in structural applications, particularly in automobiles, aerospace components, and sports equipment.