Preparation and Tribological Properties of Amorphous Ti/C Multilayers by Pulsed Laser Deposition

Abstract

Amorphous Ti/C multilayers were prepared on titanium-alloy and silicon (100)-wafer substrates by pulsed laser deposition. Films with different Ti concentration were synthesized by changing the ablating time for Ti and C targets. The morphology and microstructure of Ti/C multilayers were characterized by scanning electron microscopy (SEM), Raman spectroscopy and X-ray diffraction (XRD). Both of the Ti and C monolayers were amorphous. The metallic Ti stimulated the formation of more amorphous carbon phase by reducing the sp2 aromatic bonds and elongating the C-C chain bonds. The tribological properties of Ti/C multilayers were investigated by ball-on-disk tribometer. The pure C film and the multilayers containing more than 68.8 at.% of Ti showed low wear resistance. The multilayer contained 36.8 at.% of Ti exhibited the lowest wear rate at 3.54×10–16 m3/N·m. The formation of carbon related interlayer and its effect on tribological performance of the films were discussed.