Friction-induced nano-structural evolution of graphene as a lubrication additive

An investigation on the tribological behaviors of steel/copper and steel/steel friction pairs via lubrication with a graphene additive

“…However, the graphene in this study showed a higher degree of exfoliation because of activation by KOH at high temperature. Our previous works showed that the above graphene has good tribological properties because of its high degree of exfoliation despite some structural defects [23,25]. The highly exfoliated graphene shows much lower Van der Waals' force between layers because of larger interlayer spacing, which not only improves flexibility and self-adaptation at the friction interface but also promotes lubrication by decreasing the energy barrier of the interlayer.…”

“…2(d)). This means that the structure of the TRGO sheets that formed on the wear scars turned into ordering, which is proved to be beneficial for lubrication [23].…”

“…Steel/copper and steel/steel friction pairs lubricated by oil or oil with traditional lubrication additives do not fulfill these requirements. Graphene is a 2D laminated material that has been explored extensively as a novel lubricant additive to further improve the properties of lubrication oil [16][17][18][19][20][21][22][23][24]. It has excellent mechanical and thermal properties as well as good physical and chemical stability [25].…”

Optimization of Process Parameters for a Chemi-Absorbed Graphene Coating and Its Nano Tribological Investigation

“…Owing to its high thermal conductivity [2], low surface energy [3] and large in-plane elastic modulus [4], graphene displays outstanding frictional and wear resistant behaviors on the micro [5][6][7] and nano [8][9][10] scales. Most frequently, graphene is used as a physically absorbed solid lubricating coating [11] or additive material for lubricants [12,13]. Graphene sheets are often coated to the contact surface of parts (i.e., substrates) by physical deposition methods such as electrostatic adsorption [14] and in-situ growth [15].…”

Long-term stably dispersed functionalized graphene oxide as an oil additive

“…[1][2][3][4] Graphene possesses a nanoscale laminated structure, high mechanical strength and thermal conductivity, making it quite suitable as a lubricant additive for lubricating oils. 5,6 Compared with traditional additives, graphene has a higher loading capacity, thermal conductivity, and thermostability and is more ecofriendly. A variety of studies on graphene dispersed in base oils have been reported for improving lubricating and antiwear properties.…”