Bacteriological influence in the development of iron sulphide species in marine immersion environments

摘要

Bacteria and microbiological consortia play an important role in the corrosion of steel in marine environments. There are laboratory based experimental findings and images verifying the presence of such consortia but there are few images in the literature of the interaction between bacteria and corrosion processes. The present paper considers the marine immersion corrosion of steel and presents images which appear to show the metamorphosis of the iron in the steel to iron hydroxide and to iron-sulphur compounds. These transformations appear to involve interaction with bacteria. Scanning electron microscope (SEM) images were obtained for the specimens which were exposed to actual seawater conditions. Energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) were used to analyse the corrosion products. Inferences are made about the role of bacteria in the transformations from iron to iron-sulphur compounds.