Experimental research on tribological properties of liquid phase exfoliated graphene as an additive in SAE 10W-30 lubricating oil

Abstract In this study, the graphene was prepared by liquid phase exfoliation method, and then through microfluidization technique it was uniformly dispersed into SAE 10W-30 lubricating oil. The lubricating oils without graphene and with four different graphene concentrations were tested twice respectively on a pin-on-disc tribometer under high specific pressure of 10 MPa and low linear velocity of 0.3 m/s. After testing, the scratches on discs were observed by scanning electron microscope (SEM) and three-dimensional (3D) surface metrology system. The oil with 0.05 wt% graphene exhibited the minimum friction coefficient, lowest specific wear rate and slightest scratch. The results illustrated that the graphene dispersed into SAE 10W-30 oil with optimum concentration improved the anti-friction and anti-wear performances.