Mechanical behaviour of W–S–N and W–S–C sputtered coatings deposited with a Ti interlayer

In this research work, W–S films doped with increasing contents of nitrogen and carbon were studied. The films were deposited with a Ti interlayer to promote the adhesion to the substrate. For low N or C contents the film presents the WS2 phase, whereas for higher content they are amorphous. Doping W–S films with N or C leads to significant improvements in the hardness (from 0.6 to 6 GPa). C-containing W–S films had better tribological behaviour than N-doped ones. In relation to undoped W–S films, more than one order of magnitude reduction in the wear coefficients was reached for W–S–C films, particularly for higher applied loads in the sliding contact (10 N).