Initial Corrosion Behavior Under Biofilms Of Metal Material In Sea Water

Microbiological fouling and microbiological corrosion have been the subject of considerable study over many years, because of their direct relationship with the premature failure of metal components. Corrosion caused by Sulfate-Reducing Bacteria (SRB) is one of the most primary forms of Microbiologically Induced Corrosion (MIC). The presence and activity of SRB produce an environment which is radically different from bulk seawater in terms of surface properties, metal/ water interface structure and chemical species, leading to localized corrosion of metal material mechanism. Though much work on the corrosion problem induced by SRB has been done, it is lack of the research focus on microcosmic initial corrosion behavior beneath the biofilms, some questions about the corrosion mechanism of the metal /biofilm interface have not been solved. With the development of marine exploration, biofouling and biocorrosion have received increased attention, it is very important to study the biocorrosion behavior of home-made mayerialsin marine environment.The survival environment and growth curve of SRB were studied in sea mud in Qingdao sea area. The grouth process of biofilms of SRB covering on mica sheet was observed in-situ by AFM. The adhesive force between the tip of the probe and the surface of bacteria was measured with the force-distance curve of AFM The result showed that the adhesive force between the tip of the probe and the joint point of the cells was greater than that of the cell surface. And the biofilms were liable to be formed on the solid surface through the interaction effect of the individuals.In present work, biofilms and corrosion product films on three different metal surfaces were observed by ex-situ (SEM) and in-situ (AFM). The results showed...