Impact Abrasive Wear of Cr/W-DLC/DLC Multilayer Films at Various Temperatures

Abstract

Diamond-like carbon (DLC) films are widely used in key parts of nuclear reactors as a protective coating. A study on the abrasive wear property of Cr/W-DLC/DLC multilayer films was performed at various temperatures. Results show that the mechanism of impact wear under no sand condition is mainly plastic deformation. The multilayer film still has excellent impact wear resistance and favorable adhesion with 308L stainless steel substrate at elevated temperatures under no sand conditions. Sand particles destroy the surface of the multilayer film due to the effect of cutting and ploughing, leading to a nine-fold increase in the wear area. The impact wear mechanism changes into abrasive wear with sand addition. Oxidation wear exists on 308L stainless steel substrate material due to the removal of the multilayer film at high temperatures. More energy is absorbed for plastic deformation and material removal under sand conditions, resulting in lower rebound velocity and peak contact force than under no sand conditions. The temperature leads to the softening of the substrate; thus, the specimens become more prone to plastic deformation and material removal.