Microstructure, adhesion, in vitro corrosion resistance and tribological behavior of (Si:N)-DLC coated pure Ti

(Si:N)-DLC, Si/(Si:N)-DLC, Si3N4/(Si:N)-DLC and Si/Si3N4/(Si:N)-DLC four films were deposited on the pure Ti substrates, using a hybrid ion beam deposition system consisting of a DC magnetron sputtering and linear anode-layer ion sources, to improve the adhesion and in vitro protective performance. The microstructures and thicknesses of the (Si:N)-DLC film with different interlayers were investigated by Raman spectroscopy, X-ray photoelectron spectroscopy, atomic force microscopy and scanning electron microscopy. The mechanical and adhesion properties were evaluated by indentation and scratch tests. The corrosion resistance and wear resistance of the coated pure Ti samples were characterized by electrochemical test and friction test in the SBF solution, respectively. The results showed that the (Si:N)-DLC film containing Si3N4 structure was obtained. This (Si:N)-DLC film interacted with the Si or Si3N4 interlayer, showing an obvious transition boundary, which resulted in an increasing binding force. As a result, the Si/Si3N4/(Si:N)-DLC film showed the highest critical loads. Furthermore, it was found that the Si/(Si:N)-DLC film had excellent in vitro corrosion resistance and tribological behavior in the SBF solution.