Corrosion behavior of Q235 carbon steel in air-saturated seawater containing Thalassospira sp.

Highlights • Thalassospira sp. is isolated and identified as one of facultative iron-reducing bacteria. • The effects of Thalassospira sp. on corrosion behavior of Q235 carbon steel in air-saturated seawater is investigated. • The presence of Thalassospira sp. promotes corrosion of Q235 carbon steel. • The heterogeneous adhesion of Thalassospira sp. biofilm provides an advantage for pitting corrosion of Q235 carbon steel. Abstract Thalassospira sp. is an iron-reducing bacterium isolated from the marine environment. Effects of T. sp. on corrosion behaviors of Q235 carbon steel in air-saturated seawater were studied. Results of electrochemical measurements and weight loss indicated that the presence of T. sp. promotes Q235 carbon steel corrosion. Surface analyses results showed that heterogeneous adhesion is a typical character for T. sp. biofilm on surface of Q235 carbon steel, and pitting corrosion is induced. The corrosion mechanism model of Q235 carbon steel in air-saturated seawater containing T. sp. is proposed through surface micromorphology analyses, composition determination and current distribution. [ABSTRACT FROM AUTHOR]