Mechanical properties and thermomechanical stability of diamond-like carbon films synthesized by pulsed vacuum arc plasma deposition

Abstract

The higher sp 3 bonding fraction hydrogen-free diamond-like carbon (DLC) films were deposited on Si(1 0 0) and Cr17Ni14Cu4 stainless steel substrates by pulsed vacuum arc plasma deposition as a function of bias substrate voltage. The results show that the sp 3 content increases slightly with higher substrate bias and the effective microhardness only increases slightly. The wear resistance of the as-deposited DLC films decreases with increasing substrate bias. The effective hardness of the annealed DLC films diminishes by approximately 20% and the wear resistance decreases after annealing at 400 °C due to local adhesion decreases, even though the wear resistance of the annealed DLC films is still much better than that of the Cr17Ni14Cu4 substrate. The thermomechanical stability of hydrogen-free DLC films synthesized by pulsed vacuum arc plasma deposition is better than the DLC films containing hydrogen synthesized by PECVD.