| Abstract Scope |
Different harsh conditions limit the use of high-strength low-alloy carbon steels in upstream oil production due to corrosion, mechanical loading, and hydrogen permeation risks. This talk discusses how steel grade C110 performs under combined exposure to corrosion precursors (H₂S, pH, NaCl), mechanical stress, and hydrogen permeation. Using electrochemical methods like hydrogen permeation and electrochemical impedance spectroscopy (EIS), we studied hydrogen embrittlement mechanisms. Hydrogen permeation increases with higher H₂S concentrations, lower pH, and reduced NaCl. An adsorption isotherm is developed to understand how H₂S affects hydrogen permeation through hydrogen reduction or absorption. Notched tensile slow strain rate tests quantify susceptibility to sulfide stress cracking (SSC). Results show H₂S significantly impacts SSC susceptibility via hydrogen embrittlement. Additionally, higher NaCl concentrations lead to increased pit density, facilitating crack initiation and reducing fracture energy, thus increasing SSC risk. Understanding these correlations helps characterize steel performance in corrosive environments. |