The friction and wear behavior of bio-based graphene-coated piston ring

This study aims to investigate the tribological performance of graphene-coated piston rings from renewable resources, specifically oil palm fibre and polystyrene. Graphene coatings synthesised from oil palm fibre (OPF) and polystyrene (PS) were deposited on cast iron piston rings via chemical vapor deposition (CVD). A custom pin-on-disc tribometer was employed to measure the coefficient of friction (COF) and wear rate under varying applied loads and gas flow rates. The results indicate that OPF-based graphene coatings consistently exhibited the lowest COF and wear rates, particularly at high loads and a gas flow rate of 600 sccm. Surface morphology analysis revealed smoother surfaces with minimal ploughing, confirming enhanced wear resistance in OPF-based coatings. The findings suggest that bio-based graphene, specifically from OPF, offers a promising alternative for sustainable piston ring coatings with significant friction-reducing and wear-resistant capabilities, thereby contributing to the development of more ecofriendly internal combustion engines.