Evaluation of physical and mechanical properties of graphene oxide reinforced epoxy/Kevlar hybrid composites
Md Shadman Hassin, Mohammad Omar Faruk, Mir Iffat Ali, Shahida Begum
Abstract
Graphene is a miracle material with low density, excellent mechanical strength, electrical conductivity, molecular barrier properties and many other remarkable properties. Hence, recent research has been more focused on delving into various application areas of graphene. In this study, the effects of graphene oxide (GO) on the mechanical properties of composites based on epoxy resin and Kevlar fibers were investigated. The composites were fabricated by incorporating varying concentrations (1 %, 3 %, 5 %, 10 %, and 16 %) of graphene oxide (GO) into an epoxy matrix. The matrix was reinforced by two different wt.% (12.5 % and 25 %) of Kevlar fibers (KF). The hybrid composites were manufactured by hand lay-up process in a silicon mold at room temperature. Mechanical characterizations such as flexural, impact and hardness test exhibited an enhancement of the mechanical properties of the composites. Moreover, the measured density showed a significant reduction in density with increasing wt.% of GO. As a result, it was possible to fabricate a composite with a significant increase of specific flexural strength and specific flexural modulus. A microstructural analysis of the composites was performed by Scanning Electron Microscopy (SEM) and Energy Dispersive X-Ray Analysis (EDX). From the SEM images, it was revealed that the interphase bonding of the GO particles with Kevlar fibers and matrix was strong, thereby resulting in improved mechanical performance. It was observed that 5 wt% GO incorporation along with 25 wt% KF showed improved flexural strength, hardness and impact strength than that of sample fabricated only with Kevlar.