Corrosion behavior of Si-DLC film in simulant solutions containing CO2-H2S-Cl

• Published in: Surface & coatings technology 2024-02, Vol.478, p.130455, Article 130455
• Main Authors: Liu, Zhengyu, Yin, Pingmei, Mou, Chenglong, Cao, Xueqian, Zhang, Guangan, Xue, Qunji
• Format: Article
• Language: English
• Subjects: Influencing factor; Oil and gas fields corrosion; PECVD; Si-DLC
• ISSN: 0257-8972; 1879-3347
• DOI: 10.1016/j.surfcoat.2024.130455

Tubing and casing failure due to corrosion is a common problem in the oil industry. The Si-DLC film deposited by plasma enhanced chemical vapor deposition (PECVD) technology is expected to protect the pipeline during oil and gas exploitation. Corrosion tests were carried out in different Na2S·9H2O concentrations and temperatures in order to evaluate the corrosion resistance and stability of Si-DLC film. The results show that the Si-DLC film significantly improves the corrosion resistance of the SS304 substrate. There is no significant change on the surface of Si-DLC film with the increase of temperature, and the XPS spectrum and Raman spectrum of DLC film after corrosion possess no obvious change, which indicates that Si-DLC film possesses a great high temperature stability. The Si-DLC film is denser and it possesses excellent protective effect on the substrate compared to the corrosion product layer. The as-deposited Si-DLC film possesses excellent corrosion resistance in CO2-H2S-Cl− environment and this study provides a promising protective material for the inner surface of the pipeline during oil and gas exploitation. •A high-performance protective film for the field of oil and gas exploitation was provided.•The stability of DLC film under the influence of environmental factors was studied by analyzing the composition and morphology before and after corrosion.•A corrosion model for Si-DLC film at different temperatures and H2S concentrations was proposed.