Mechanism of Ennoblement by Bioflims on Active/Passive Alloys Immersed in Seawater, Tri-Service Committee on Corrosion Proceedings

Abstract

The purpose of this paper is to present a brief review of how microbial fouling films affect the corrosion behavior of passive metals in natural waters. It has often been reported that microbial films shift the open circuit corrosion potential (OCP) of passive metals in the positive (or noble) direction and enhance the kinetics of the cathodic oxygen reduction reaction. The significance of this effect lies in it's influence on localized corrosion initiation and propagation. In chloride bearing waters, initiation of pitting and crevice corrosion is statistical, with the probability of initiation increasing directly with chloride ion activity and OCP. Thus at a given chloride level, the probability of localized corrosion initiation is increased by anything (such as a biofilm and its metabolic products) that causes the OCP to become ennobled.

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Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1994
Accession Number
ADA331029

Entities

People

  • Stephen C. Dexter

Organizations

  • University of Delaware

Tags

DTIC Thesaurus Topics

  • Alloys
  • Chemistry
  • Corrosion
  • Current Density
  • Environment
  • Films
  • Galvanic Corrosion
  • Heavy Metals
  • Materials
  • Metals
  • Microorganisms
  • Oxides
  • Oxygen
  • Oxygen Electrodes
  • Peroxides
  • Resistance
  • Stainless Steel

Readers

  • Materials Science and Engineering.
  • Systems Analysis and Design

Technology Areas

  • Biotechnology