TY - CONF A1 - Hampel, Marco A1 - Özcan Sandikcioglu, Özlem T1 - Application of localized electrochemical methods to the analysis of microbiologically influenced corrosion N2 - The corrosion of stainless steel components is a problem of global scale, economically as well as in regards to the safety of industrial equipment and facilities. With microorganisms involved (microbial influenced corrosion, MIC), the problem becomes more complex. Iron reducing bacteria (IRB) for example accelerate the corrosion of iron based materials like stainless steel via the reduction of iron oxides in the passive layer. When co-cultivated with iron oxidizing bacteria, IRBs can induce deep, heterogeneously distributed pits on stainless steel surfaces. The analysis of localized corrosion – or pitting corrosion – is of great relevance since it can lead to unpredictable material failure. In general, macroscopic electrochemical methods are not capable of providing information about the spatial heterogeneity of a sample and thus need to be complemented by multi-electrode based techniques or scanning electrochemical methods. The aim of this work is to develop methods for the analysis of localized corrosion, on stainless steel surfaces induced by IRB biofilms. The greatest challenge is to address the complexity of two heterogeneous systems at the metal/biofilm interface. First there is the variation in the passive layer composition and microstructure. Secondly, the microbial biofilm with its heterogeneous tree-dimensional structure resulting in local differential aeration cells and electrochemical parameters. To be able to differentiate between individual effects, artificial biofilms mimicking the physical properties of a natural biofilm are used in this study as model systems. This artificial biofilm is applied on a multi-electrode probe to identify local anodic sites during exposure experiments. The detailed analysis of active sites by means of scanning electrochemical microscopy (SECM) allows the investigation of local properties within the biofilm and its immediate vicinity. The presented analytical approach delivers promising results in clarifying how localized corrosion of stainless steels develops chronologically and spatially in the presence of IRBs. Furthermore, our results on model systems provide the basis for the application of the methodology for the investigation of natural or multi-species biofilms in the future. T2 - Electrochemistry 2016 CY - Goslar, Germany DA - 26.09.2016 KW - MIC KW - Microbiologically influenced corrosion KW - Scanning electrochemical microscope KW - Multielectrode assemblies PY - 2016 AN - OPUS4-38198 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -