Effect of graphite nanoplatelet content on the friction and wear properties of basalt fiber-reinforced polymer composites

Basalt fiber-reinforced polymer (BFRP) composites have attracted considerable attention as lightweight structural materials owing to their excellent mechanical properties, heat resistance, chemical resistance, and cost-effectiveness. However, friction and wear damage can accumulate under repeated contact and sliding conditions, requiring systematic evaluation and improvement of their tribological performance. In this study, BFRP/graphite nanoplatelet (GNP) composites containing 0, 5, 10, and 15 wt% GNPs were fabricated to enhance the dry tribological properties of BFRP composites. GNP/epoxy mixed resins were prepared through sequential mechanical mixing, degassing, and ultrasonication, followed by composite fabrication using vacuum-assisted resin transfer molding. Structural characterization confirmed the successful incorporation of GNPs into the BFRP composites. Dry ball-on-disk tests were conducted under normal loads of 5 and 10 N to evaluate the effect of GNP content on friction and wear behavior. The results showed that both the average coefficient of friction and cross-sectional wear area decreased with increasing GNP content under both loading conditions. In particular, the 15 wt% GNP specimen exhibited an approximately 25% lower coefficient of friction and a 72% reduction in wear area under the 5 N load compared with the neat BFRP specimen, while a 21% reduction in wear area was also observed under the 10 N load. Wear-track analyses further revealed that the wear scar area decreased with increasing GNP content. These improvements are attributed to the solid lubricating effect and interfacial protection provided by GNPs. Therefore, incorporating GNPs is an effective strategy for improving the dry tribological performance of BFRP composites.