J. Mater. Sci. Technol. ›› 2021, Vol. 92: 109-119.DOI: 10.1016/j.jmst.2021.02.039

• Research Article • Previous Articles     Next Articles

Effect of sulfate-reducing bacteria on hydrogen permeation and stress corrosion cracking behavior of 980 high-strength steel in seawater

Meiying Lv, Xuchao Chen, Zhenxin Li, Min Du*()   

  1. Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China
  • Received:2020-11-25 Revised:2021-02-05 Accepted:2021-02-19 Published:2021-11-30 Online:2021-05-02
  • Contact: Min Du
  • About author:* E-mail address: ssdm99@ouc.edu.cn (M. Du).

Abstract:

980 high-strength steel has been widely used in marine engineering structures due to its high strength and toughness. However, it is easily affected by the harsh environmental conditions (such as the presence of sulfate-reducing bacteria, SRB), leading to the risk of stress corrosion cracking (SCC). In this paper, the effects of SRB and its metabolites on hydrogen permeation and SCC mechanism of 980 steel in seawater solution were investigated by slow strain rate tensile test, scanning electron microscope, X-ray energy spectroscopy, Raman spectroscopy and Devanathan-Stachurski double electrolytic cell. Results demonstrated that the SCC susceptibility of 980 steel was promoted in the presence of SRB, which was related to the cultivation time of the bacteria. When SRB were cultivated for 3d and 6d, the SCC mechanism was controlled by hydrogen-induced cracking (HIC); while the cultivation time extended to 11d, the SCC of 980 steel was under the combined effect of the anodic dissolution (AD) and HIC mechanism. When cultivated for 16d, the SCC of 980 steel was caused by the dominant AD. Both the SRB accelerated hydrogen permeation under cathodic depolarization process and SRB assisted AD (pitting corrosion) played an enhancing role in promoting SCC susceptibility of 980 steel.

Key words: Stress corrosion cracking, Sulfate-reducing bacteria, Microbiologically influenced corrosion, 980 High-strength steel, Seawater