Search

The effects of alternating current (AC) and Bacillus cereus (B. cereus) on the stress corrosion behavior and mechanism of X80 pipeline steel were investigated in a Beijing soil solution in this study. Both AC and B. cereus can promote the generation of pits in X80 steel. B. cereus is a type of nitrate-reducing bacteria and hence nitrate reduction occurs at the bottom of the corrosion product film or the biofilm. Meanwhile, the anode accelerates the dissolution of X80 steel and generates some pits in the local working area. The synergistic effect of AC and nitrate- reducing bacteria (NRB) promotes X80 steel corrosion and increases its susceptibility to stress corrosion cracking (SCC)., (Copyright © 2019 Elsevier B.V. All rights reserved.)

In this study, the corrosion behavior of X80 pipeline steel in the presence of Brevibacterium halotolerans (B. halotolerans) was investigated by surface analysis and electrochemical measurements. Results show that B. halotolerans can attach to the surface of X80 steel, and the entire surface is covered with B. halotolerans. The corrosion products induced by B. halotolerans were FeOOH, Fe 2 O 3 and FeSO 4 . X80 steel corrosion was accelerated in the presence of B. halotolerans and was susceptible to pitting corrosion. The formation of pitting corrosion could be due that the B. halotolerans oxidization of elemental iron in X80 steel to either obtain electrons from the reduction of nitrate in the underlying biofilm or in the damaged corrosion product film., (Copyright © 2018 Elsevier B.V. All rights reserved.)