Mechanical and tribological characterization of graphene nanoplatelets/Al₂O₃ reinforced epoxy hybrid composites

Abstract

This study aimed to determine the effects of varying Aluminum oxide (Al₂O₃) and Graphene Nanoplatelets (GNP) concentrations on epoxy-based polymer composites’ mechanical and tribological characteristics. Al₂O₃ (1 to 5 wt.%) and GNP (0 to 1 wt.%) reinforced epoxy matrix composites were produced with sonication and stirring magnetic route. Mechanical, microstructural and tribological properties of composites were investigated via X-ray diffraction (XRD), Archimedes’ Method, Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDX), Raman spectroscopy, hardness, impact, tensile, compressive and wear tests. The highest ultimate tensile strength and compressive strength were found at 62.83 and 137 MPa for 3 wt.% reinforced Al₂O₃ epoxy matrix composites, and it was observed that there was a 38% and 17% increase compared to neat epoxy, respectively. The highest impact strength was found for 3 wt.% Al₂O₃ and 1 wt.% GNP-reinforced composites and increased by 19% compared to neat epoxy. The best hardness was found for 3 wt.% reinforced Al₂O₃ and 0.25 wt.% GNP-reinforced composite, and there was a 22% increase in hardness compared to neat epoxy. Also, the highest wear resistance (1.686x10⁻⁶ mm³/Nm) and lowest Coefficient of Friction (COF, 0.13755) were determined for the same specimen.

Keywords:

• Hybrid composites
• epoxy
• aluminum oxide
• graphene
• mechanical behavior

Acknowledgment

We thank İnal Kaan Duygun from Bursa Technical University for his help during the tensile tests.