Preparation, characterization and lubrication performances of graphene oxide-TiO2 nanofluid in rolling strips

Abstract

Graphene oxide (GO) and anatase TiO2 are tried as lubricating additives for nanofluids due to their unique structure and physical properties. In this article, anatase TiO2 modified GO (GO-TiO2) have been synthesized via an improved and facile solvothermal method. The physical and chemical properties of as-prepared samples were characterized by means of X-ray diffraction, Fourier transformed infrared spectra, Raman spectra and transmission electron microscopy. The tribological properties and rolling lubrication performance of the control group and 0.5 wt% of GO, TiO2, GO + TiO2, GO-TiO2 nanofluids were investigated using a four-ball tribometer and two-high rolling mill. The microscopic morphologies of the rolled strips were measured and analyzed by a series of physical characterizations. The results showed that spherical TiO2 was successfully anchored on GO nanosheets. 0.5 wt% of GO-TiO2 nanofluid had excellent friction reducing and wear resistance. It had the largest film thickness and was nanoscale (28.07 nm). And the rolled strip lubricated by 0.5 wt% of GO-TiO2 nanofluid had few defects and minimal roughness. The superior lubricating properties of GO-TiO2 nanocomposites were attributed to the excellent dispersion stability and the formation of absorption films, carbonaceous protective films and transfer films.