Tribological Properties of Graphene as Effective Lubricant Additive in Oil on Textured Bronze Surface

Abstract

The friction and wear properties of graphene (GP) as a lubricant additives were investigated by means of a UTM-2 tribometer via a ball on plate contact reciprocating sliding. The molecular structure and morphology of graphene nano sheets were characterized by TEM, SEM, XRD, IR and Raman spectroscopy. The friction and wear test was performed with lubricant of PAO4 oil without and with addition of 0.01% graphene (GP) respectively at different temperatures for the textured bronze with different ratio of textured area. The results show that GP can effectively reduce the friction and wear, especially at 60°C and 100°C. For the simple PAO4 oil, the bronze with untextured surface exhibits the lowest friction coefficient and wear rate at 60°C and 100°C; whilst, with the increasing ratio of the textured area, the friction coefficient and wear rate increase. For graphene-containing PAO4 lubricating oil, the friction coefficient is lower for the bronze with 5% textured area, while higher for those with 20%; the wear rate is lower for the bronze with 10% textured area.