Investigation of low-percentage graphene reinforcement on the mechanical behaviour of additively manufactured polyethylene terephthalate glycol composites

The current work investigates the influence of graphene on the mechanical properties of additive-manufactured polyethylene terephthalate glycol (Prince Edward IslandTG) composites. To this end, the graphene content is varied by 0.02 wt.%, 0.04 wt.%, 0.08 wt.%, and 0.1 wt.% to obtain different compositions of PETG/graphene composites. The filaments were prepared by mixing the PETG pellets and graphene flakes into the required quantity. Further, the mixture is extruded using a single screw extruder into small filaments with a 1.75 mm diameter. Using fused deposition modelling (FDM), the specimens were 3D printed following ASTM requirements. The fabricated PETG/graphene specimens are assessed for their mechanical properties, such as tensile, compression, flexural and impact characteristics. Finally, the fractography of the tested specimens is analysed using a scanning electron microscope (SEM). The experimentation of PETG/graphene composites reveals that the optimum mechanical properties can be achieved when PETG is reinforced with 0.04 wt.% of graphene. As opposed to virgin PETG, an increment of 89.71%, 81.76%, 21.60%, and 81.25% is witnessed in the tensile, compression, flexural, and impact strengths of the PETG/0.04 wt.% graphene composite. The outcome of this work is believed to pave the way for broadening the applications of graphene-based composites in electromechanical and smart structure engineering domains.