Nanotribology of silver and silicon doped carbon coatings

Abstract

Amorphous hydrogenated carbon coatings a-C:H become very popular materials mainly because of their excellent properties such as low coefficient of friction, high hardness, good anti-wear and corrosion properties. More and more often are carried works aimed at improvement of biocompatibility and adhesion of bacterial cells by doping diamond-like carbon (DLC) coating with third element. Among them recently a great majority is devoted to carbon coatings doped with silver or silicon. The presence of silver in the coating ensures protection of the implant against the disadvantageous influence of bacteria and fungi causing biofilm associated infections, local inflammation and other implant-tissue reactions. Incorporation of silicon promotes osteointegration and leads to the enhancement of mechanical and tribological properties of the coating, which is beneficial for biomedical applications.Silver and silicon incorporated DLC coatings were prepared by a hybrid Radio Frequency Plasma Assisted Chemical Vapor Deposition/Magnetron Sputtering deposition technique on AISI316L substrates. Obtained coatings were characterized in terms of morphology, surface topography and mechanical properties. Tribological properties of the coatings were measured by lateral force microscopy and reciprocating sliding test using nanoindenter.