Tribological behavior of graphene oxide-Fe3O4 nanocomposites for additives in water-based lubricants

Graphene oxide-Fe3O4 (GO-Fe3O4) nanocomposites were synthesized via the solvothermal method and used as lubricant additives. The tribological tests and a series of characterization techniques were conducted to understand the lubrication mechanism of GO-Fe3O4 nanocomposite. The GO-Fe3O4 nanocomposites exhibited excellent tribological properties due to high dispersion stability in water. Friction results indicated that the GO-Fe3O4 can significantly improve the tribological properties and the friction coefficient and wear scar diameter had been reduced by 33.6% and 32.3% compared with base fluid, respectively. Raman results showed that the GO nanosheets formed a protective film on the contact interfaces, which facilitated shear, reduced the wear and inhibited the tribo-corrosion. The lubrication mechanism was attributed to the synergistic lubrication effect between the Fe3O4 nanospheres and the GO nanosheets.