Scholarlink

<p>API 5L Grade X60 pipeline steel is widely used in oil and gas transportation systems due to its mechanical robustness and corrosion resistance. This study examines the electrochemical performance and surface degradation characteristics of API X60 steel in a simulated oilfield environment containing varying NaCl concentrations (3.5, 5.5, and 7.5&#xa0;wt.%), under both aerated and CO<sub>2</sub>-saturated conditions. Potentiodynamic polarization and Tafel extrapolation were employed to quantify corrosion kinetics, while electrochemical impedance spectroscopy (EIS) was used to evaluate polarization resistance and passive film behavior. Results revealed a substantial increase in corrosion current density (<i>i</i><sub>corr</sub>) and corrosion rate with rising chloride content. Under CO<sub>2</sub>-saturated conditions, a semi-protective surface layer, likely iron carbonate (FeCO<sub>3</sub>), was formed and contributed to partial passivation. However, this protective layer deteriorated with increasing Cl<sup>−</sup> concentrations, as indicated by lower polarization resistance and a shift toward more negative corrosion potentials. SEM and EDS analyses confirmed the presence of localized corrosion and the presence of Fe, O, C, and Cl in the corrosion products. Raman spectroscopy identified FeCO<sub>3</sub> and iron oxide phases, with diminished signal intensity at higher salinity, suggesting reduced passive film integrity. These findings offer insight into the corrosion mechanisms of pipeline steels under CO<sub>2</sub>-rich and saline conditions, which are relevant to oil and gas infrastructure applications.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Electrochemical Investigation of API X60 Steel in Simulated Oil Environment: Corrosion Behavior and Surface Characterization

  • 期刊论文

  • 发表日期：

    2026年2月17日

查看全文
  • Biplab Baran Mandal,
  • Vikash Kumar,
  • Binod Barai,
  • Buddhadeb Oraon

摘要

API 5L Grade X60 pipeline steel is widely used in oil and gas transportation systems due to its mechanical robustness and corrosion resistance. This study examines the electrochemical performance and surface degradation characteristics of API X60 steel in a simulated oilfield environment containing varying NaCl concentrations (3.5, 5.5, and 7.5 wt.%), under both aerated and CO2-saturated conditions. Potentiodynamic polarization and Tafel extrapolation were employed to quantify corrosion kinetics, while electrochemical impedance spectroscopy (EIS) was used to evaluate polarization resistance and passive film behavior. Results revealed a substantial increase in corrosion current density (icorr) and corrosion rate with rising chloride content. Under CO2-saturated conditions, a semi-protective surface layer, likely iron carbonate (FeCO3), was formed and contributed to partial passivation. However, this protective layer deteriorated with increasing Cl− concentrations, as indicated by lower polarization resistance and a shift toward more negative corrosion potentials. SEM and EDS analyses confirmed the presence of localized corrosion and the presence of Fe, O, C, and Cl in the corrosion products. Raman spectroscopy identified FeCO3 and iron oxide phases, with diminished signal intensity at higher salinity, suggesting reduced passive film integrity. These findings offer insight into the corrosion mechanisms of pipeline steels under CO2-rich and saline conditions, which are relevant to oil and gas infrastructure applications.