In the past, microbiologically influenced corrosion (MIC) has been identified as one of the main degradation mechanism in materials. Steel pipelines in the oil industry frequently show MIC since the microorganisms use the metallic material as a growth substrate. They produce different chemical compounds, which modify the chemical characteristics of the environment around the specimens. New steel compositions are commonly tested in MIC environments to evaluate their corrosion resistance to microbial activity. API-XL70 steel is a relatively new material with physical properties designed for pipelines applications. Direct current and electrochemical noise techniques were used to evaluate the steel probes behavior. The experimental results showed slight variations in the corrosion velocities obtained with Tafel
extrapolations and also linear polarization resistance (Rp). However, the experimental results obtained with the electrochemical noise technique showed pronounced differences of the steel behavior in the media with and without microorganisms.
Keywords: MIC, SRB, XL70 steel, structure characterization, electrochemical techniques.