Wear and Tribological Properties of Silicon-Containing Diamond-Like Carbon (Si-DLC) Coatings Synthesized with Nitrogen, Argon Plus Nitrogen, and Argon Ion Beams

摘要

Hard, adherent, and low-friction silicon-containing diamond-like carbon coatings (Si-DLC) have been synthesized at room temperature by 40 keV (N(+) + N2(+)), 50% Ar(+)/50% (N(+) + N2(+)), and Ar(+) ion-beam-assisted deposition (IBAD) of a tetraphenyl-tetram ethyl-trisiloxane oil on silicon and sapphire substrates. X-ray diffraction analysis indicated that all coatings were amorphous. The average coating wear rate and the average unlubricated steel ball-on-disk friction coefficient, mu, decreased with increasing fraction of nitrogen in the ion beam, along with an increase in the average coating growth rate. The Knoop microhardness and nanohardness values of the coatings synthesized by the mixed argon and nitrogen ion beam were higher than the values for the coatings synthesized with 100% nitrogen or 100% argon ion beams. These friction/wear improvements are tentatively attributed to both increased hardening due to greater penetration and ionization induced hardening by the lighter (N) ions and to the presence of SiO2 on the surface of N-bombarded samples.