The tribo-corrosion behavior of monolayer VN and multilayer VN/C hard coatings under simulated seawater

The monolayer VN as well as multilayer VN/C coatings were obtained on 316 L steel via physical vapor deposition (PVD) technology. Structure, mechanical property and tribo-corrosion behavior of monolayer VN and multilayer VN/C coatings under simulated seawater were estimated by corresponding detection equipment. After analysis, C nanolayer could break the grain growth of VN phase, which would enhance the coating toughness and inhibit the source of crack. At the same time, the multilayer structure interface could suppress the dislocation movement. In tribo-corrosion process, the corrosion current density (icorr) of VN/C coating was 2.71 × 10−6 A/cm2, which was 70.47% lower than that of VN coating (9.18 × 10−6 A/cm2), implying that the nano-multilayer structure of VN/C coating showed a strong barrier effect on corrosion medium. Moreover, the C nanolayer not only suppressed the permeation of simulated seawater, but also formed the transfer film to protect the substrate. Thus, the multilayer VN/C coating revealed stronger anti-wear and anti-corrosion abilities than the monolayer VN coating.