Corrosion and wear resistance properties of multilayered diamond-like carbon nanocomposite coating

Multilayered diamond‐like carbon (DLC) nanocomposite coating has been deposited on siliconand stainless steel substrates by combination of cathodic arc evaporation and magnetronsputtering. In order to make DLC coating adhered to metal substrate, a chromium interlayerhas been deposited with constant bias voltage of−150 V applied to the substrate. Dense multi-layered coating consists of metallic or nonmetallic and tetrahedral carbon (ta‐C) layers with totalthickness of 1.44μm. The coating has been studied for composition, morphology, surface nature,nanohardness, corrosion resistance, and tribological properties. The composition of the coatinghas been estimated by energy‐dispersive spectroscopy. Field‐emission scanning electron micros-copy and atomic force microscopy have been used to study the surface morphology and topog-raphy.ID/IGratio of ta‐C:N layer obtained from Raman spectroscopy is 1.2, indicating the disorderin the layer. X‐ray photoelectron spectroscopy studies of individual ta‐C:N, CrN, and Cr‐dopedDLC layers confirm the presence of sp2C, sp3C, CrN, Cr2N, and carbidic carbon, and sp2C,sp3C, and Cr carbide. Nanohardness studies show the maximum penetration depth of 70 to 85nm. Average nanohardness of the multilayered DLC coating is found to be 35 ± 2.8 GPa, andYoung's modulus is 270 GPa. The coating demonstrates superior corrosion resistance with betterpassivation behavior in 3.5% NaCl solution, and corrosion potential is observed to move towardsnobler (more positive) values. A low coefficient of friction (0.11) at different loads is observedfrom reciprocating wear studies. Wear volume is lower at all loads on the multilayered DLCnanocomposite coating compared to the substrat