Effect of Temperature on the Corrosion Behavior of API X80 Steel Pipeline

摘要

The electrochemical behavior of API X80 pipeline steel in 3.5% of NaCl solution containing differentconcentrations of H2S at different temperatures was investigated. Corrosion behavior of the API X 80steel material was evaluated using electrochemical impedance spectroscopy and potentiodynamicpolarization measurements. The profilometry, X-ray diffraction, and scanning electron microscopywere employed to characterize the corroded API X 80 steel surfaces. The results showed that thecorrosion rate of API X80 steel increased with increasing temperature. Pitting corrosion was observedat lower temperatures, while cracks and sulfide layers of mackinawite and cubic FeS were observed onthe corroded steel surface as the temperature increased. Displacement of iron oxide film with a non- protective iron sulfide film was found to be responsible for the pitting corrosion of the API X80 steel.