The corrosion and tribological behaviors of DLC film in CO2 saturated NaCl solution with high Cl− concentration

The failure of pipelines during oil and gas exploitation is a pressing issue in the oil and gas industry. The high permeability of chloride ions (Cl−) alters the corrosion morphology of the N80 substrate and diminishes its ability to impede the penetration of corrosive substances. This study aims to deposit DLC films on the inner surface of N80 pipeline using plasma enhanced chemical vapor deposition (PECVD), and investigate the corrosion and friction behavior of DLC films in CO2 saturated NaCl solutions with varying Cl− concentrations. The results indicate that the change in Cl− concentration possess minimal impact on the DLC film. The corrosion current density of DLC films in CO2 saturated NaCl solution with three different Cl− concentrations is one order of magnitude lower than that of the N80 substrate. Moreover, a transfer film can still form in high-concentration CO2-saturated NaCl solutions, reducing wear. DLC film demonstrates exceptional stability, corrosion resistance, and wear resistance, making it an ideal material for safeguarding pipelines during oil and gas exploitation.