Influence of SiO2 in TiO2 matrix on tribological properties of TiO2

TiO2 thin film was grown on a glass substrate by sol–gel process followed by high temperature treatment at 500◦C. TiO2 films demonstrated a very good wear resistance, endurance life and enhancing tribological characteristics. Energy Dispersive X-ray Spectroscopy (EDS) was used to indicate elements that contain in the film. EDS result showed that besides Ti, O and Si elements there is a small amount of Ca, Na, Mg elements diffused from the glass substrate. X-ray Diffraction (XRD) analysis indicated that TiO2 films contain only anatase phase. The morphologies of the original and worn surfaces of the samples were analyzed by means of Scanning Tunneling Microscope (STM) and Scanning Electron Microscopy (SEM). The tribological properties of TiO2 thin film sliding against the AISI-52100 steel pin were evaluated with a pin on disk system. The results indicate that TiO2 films are superior in reducing friction and resisting wear compared with that of glass substrate. SEM observation of worn surfaces indicates that the glass wear is characteristic of brittle fracture and severe abrasion. The superior friction reduction and wear resistance of multilayer TiO2 films are attributed to slight plastic deformation as well as good adhesion of the film to the substrate.

Keywords:

Thin film , TiO2 , SiO2 , Tribological properties , Sol-gel