Chemisorption of thermal reduced graphene oxide nano-layer film on TNTZ surface and its tribological behavior

In this study, reduced graphene oxide (RGO) sheets are chemisorbed on titanium alloy substrate by making use of 3-aminopropyltriethoxysilane (APTES) as an intermediate coupling agent. The silanol moiety of the APTES molecule is chemically bonded on the substrate surface and the other end of the molecule-amino group is covalently connected with oxygen functional groups of graphene oxide (GO). A thermal reduction process is then carried out to prepare APTES-RGO nano-layer on the surface of Ti-29Nb-13Ta-4.6Zr (TNTZ) alloy. Chemical characterization and surface morphology analyses are performed by XRD, XPS, AFM, SEM measurements. The results show that the prepared films are of nanoscale in thickness, with chemisorptive bonds to the substrate. Furthermore, tribology properties of the films are investigated by UMT tester. Tribological results indicate that the prepared APTES-RGO film lowers the coefficient of friction and improves anti-friction properties of titanium alloy under dry friction. Tribology mechanism of the film is discussed in the end.