Effect of the Local Damage of a Sulfide Film Formed on Steel Surfaces in H₂S Environments

摘要

The electrochemical corrosion behavior of X80 pipeline steel in distilled water with saturated H 2 S at323 K was evaluated, and the corrosion products were characterized. The results showed thatmackinawite and cubic FeS were the primary and secondary crystalline phases observed, respectively.In addition, a series of changes in their size and shape occurred during the immersion processes. Thesulfide film that formed on the steel surfaces enhanced the corrosion resistance. Moreover, zeroresistance ammeter measurements showed that the galvanic effect was introduced between the freshand sulfide film-covered steel electrodes, and then it decreased, and disappeared, indicating thatsubstantial local corrosion cannot be introduced because of the local damage of the sulfide film.