Marine Bacteria and Localized Corrosion on Polymer Coated Steel: Cause and Effect

摘要

Diagnosis of microbiologically influenced corrosion on iron- containing substrata exposed in marine environment cannot be based solely on spatial relationships between large accumulations of bacterial cells and iron corrosion products. Field experiments were designed to evaluate the relationship between marine bacteria and localized corrosion and coated mild steel. In all cases, the distribution of bacteria was strongly influenced by the presence of iron corrosion products independent of coating combinations. In the presence of cathodic protection, coating defects were filled with calcareous deposits and few bacterial cells. Results demonstrate that bacteria are preferentially attracted to iron corrosion products in coating defects and that attraction is more influential than topography in determining the spatial distribution of bacterial cells.