Improved mechanical properties of graphene-modified basalt fibre–epoxy composites

In industrial applications, the potential of basalt fibre-reinforced polymer (BFRP) composite pipes as a compelling alternative to glass and carbon fibre-reinforced composite pipes is recognized. Their high recyclability makes them a viable option for aerospace, marine, and automotive applications. In this study, a comparison is made between the mechanical properties of virgin basalt–epoxy composite pipes and graphene-modified counterparts. To conduct the experiments, pipe section specimens were prepared using a flex grinding machine. Graphene nanoplatelets (GnPs), serving as an exceptional reinforcing material, were uniformly incorporated into the basalt–epoxy composites at a specific concentration. The inclusion of these nanoplatelets resulted in significant changes in mechanical stiffness compared to the virgin basalt–epoxy composite pipes. A series of tests, including uniaxial tensile, Charpy impact, microhardness, Shore D hardness, uniaxial 3-point bending, and dynamic displacement transmissibility tests, were carried out to assess the mechanical properties of both graphene-reinforced and virgin basalt–epoxy pipes. The findings indicated that the pure basalt–epoxy composite exhibited lower ductility compared to the graphene basalt–epoxy composites after undergoing uniaxial mechanical loading. Non-destructive dynamic mechanical vibration testing was used to investigate the complex mechanical response of the materials under examination. The observed complex frequency-dependent responses reflected the mutual ductile/brittle mechanical performance of the developed composites.