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Microbiologically influenced corrosion inhibition (MICI) due to bacterial contamination
Author(s) -
Nagiub A.,
Mansfeld F.
Publication year - 2001
Publication title -
materials and corrosion
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.487
H-Index - 55
eISSN - 1521-4176
pISSN - 0947-5117
DOI - 10.1002/1521-4176(200111)52:11<817::aid-maco817>3.0.co;2-1
Subject(s) - electrochemical noise , metallurgy , corrosion , rock blasting , chemistry , contamination , brass , pitting corrosion , nuclear chemistry , electrochemistry , materials science , electrode , copper , ecology , biology , geotechnical engineering , engineering
Microbiologically influenced corrosion inhibition (MICI) has been observed for Al 2024, mild steel, cartridge brass and stainless steel when an artificial seawater (AS) solution containing growth medium was contaminated by bacteria. In this case the test electrodes had been sterilized by immersion in ethanol, while the test cell had been sterilized in an autoclave. In tests in which all parts had been sterilized in an autoclave contamination did not occur and the corrosion behavior was similar to that obtained in AS without growth medium. Impedance data clearly showed that pitting did not occur for Al 2024 in the contaminated solution, while for mild steel and brass corrosion rates were greatly decreased. Analysis of electrochemical noise (EN) data demonstrated that the power spectral density (PSD) plots of the current fluctuations for Al 2024 and mild steel had changed to lower levels, while the PSD plots for the potential fluctuations remained unchanged. The slopes of the potential and current PSD plots were unchanged due to bacterial contamination, while the localization index (LI) was close to zero in all cases.