Preparation and Characterization of Ti Dopped MoS2 Composite Films Deposited by Closed-Field-Magnetron Sputtering and their Tribological Properties
The Ti-doped MoS2 composite films were prepared on single-crystal Si(100)and 304 stainless steel sub-strates by adjusting the sputtered Ti targets at different currents using closed-field-magnetron sputtering deposition tech-nique,respectively.The morphology,microstructure and the element content of the films were characterized using field emission scanning electron microscopy,X-ray photoelectron spectroscopy and transmission electron microscopy.The me-chanical and tribological properties of the films under atmospheric conditions were evaluated by using nanoindentation and ball-on-disk friction testing device as a function of the content of Ti in the films.The results demonstrate that the content of Ti element in the composites films increases with increasing sputtering current,which can effectively obstruct the growth size of MoS2 crystallites during the deposition process,thus transforming MoS2 from a lamellar structure with large size to amorphous structure with ordered in short-range and disordered in long-range.Especially,the Ti/MoS2 composite films with Ti element atomic fraction of 18.55%prepared at a sputtering current of 1.0 A exhibit desirable densities and hard-ness,while the Ti element preferentially bound with O at the friction interface compared with MoS2,which improves the MoS2 oxidation resistance and enhances the tribological properties of the film.