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Microbiologically influenced corrosion on rails

IR@CECRI: CSIR-Central Electrochemical Research Institute, Karaikudi


Field	Value

Title	Microbiologically influenced corrosion on rails

Creator	Maruthamuthu, S. Nagendran, T. Anandkumar, B. Karthikeyan, M.S. Palaniswamy, N. Narayanan, G.

Subject	Microbiolcorrosion Corrosion Science and Engineering

Description	Corrosion of rails has been a cause of concern for the Southern Railways. Out of many causes, corrosion due to toilet droppings is more pronounced. In this study, the role of bacteria, viz. heterotrophic bacteria, manganese oxidizers, iron bacteria and ureolytic bacteria on rails have been studied. The attachment of rod- and cocci-shaped bacteria were noticed on the corroded rail sample. A porous rust layer and fine cracks were noticed on the steels. Twenty bacterial strains were identified by molecular technique and most of the bacteria were positive in citrate and urease test, where 85% species could tolerate high pH 9.0. X-ray photoelectron spectroscopy revealed that FeOOH in the bare steel was converted to ferric oxides and hydroxides due to bacterial corrosion. When the rail sample was tested at low AC perturbations, the biofilm provided protection to the rails. However, at higher anodic potentials, the biofilm was not able to protect the bare material. It could be assumed that the ureolytic bacteria and iron/manganese oxidizers may create differential pH gradient on the metal surface which enhances the electrochemical reaction of the metal surface.

Publisher	Indian Academy of Sciences

Date	2011

Type	Article PeerReviewed

Format	application/pdf

Identifier	http://cecri.csircentral.net/3066/1/024-2011.pdf Maruthamuthu, S. and Nagendran, T. and Anandkumar, B. and Karthikeyan, M.S. and Palaniswamy, N. and Narayanan, G. (2011) Microbiologically influenced corrosion on rails. Current Science, 100 (6). pp. 870-880. ISSN 0011-3891

Relation	http://cecri.csircentral.net/3066/