Study on the friction and wear performance of graphene/porous bronze composites

Abstract The porous surface of air bearings may suffer from surface scratching and wear issues during the start-stop processes or under extreme working conditions. To enhance the lubrication properties and improve the service life of the porous restrictors, the graphene/porous bronze composites were prepared by combining powder metallurgy (PM) and chemical vapor deposition (CVD) in this study. On this basis, studies on the friction and wear performance of porous composites were carried out. The prepared porous composites and the friction surfaces were described by various means such as friction coefficient, morphology scanning, surface roughness, SEM, and EDS, which revealed the friction and wear process of the composites. Moreover, during the composite generation, the flow rates of carbon sources were set to be 3, 6, 9, and 12 sccm, respectively, to investigate the effect of graphene content on the lubrication properties of the original porous matrix. The experimental results showed that the lubricating performance of the composite was optimized at a flow rate of 12 sccm. Compared to the original porous bronze, the friction coefficient was decreased by 8.4%, and the wear rate was reduced by 10.5%. Furthermore, the research findings indicated that the grown graphene also affects the sintering process of the porous matrix, leading to weak connections between powders and differences in the final pore structure. Thus, the final pore structure, along with the presence of graphene, jointly influences the friction and wear performance of the porous composites.