Molecular simulations of sliding process between Fe and DLC films on various boundary conditions

Diamond-like carbon (DLC) films have been extensively studied over the past decades due to their unique combination of properties, such as a low friction coefficient, high hardness, high wear resistance and chemical inertness. But many results of DLC films exhibit a wide range of sometimes contradictory tribological properties. In the experiment, isolating the influences of factors, such as film structure, testing conditions and environments effects has proven different. In the paper, molecular dynamics (MD) simulations were used to study a sliding friction process between Fe and DLC films on various boundary conditions (such as: water, oil and no lubrication). The results have been shown that for all the boundary conditions, boundary lubrication occurs, even where there is no lubricant between the Fe and DLC films. The Lubrication boundaries have little effect on the tribological properties between Fe and DLC films. The friction forces for all the cases are almost the same.