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In this work, electrochemical monitoring of stress corrosion cracking (SCC) behavior of a X70 steel in acidic synthetic soil solution during the slow strain rate test (SSRT) was performed by electrochemical noise (EN) using the conventional arrangement of symmetrical electrodes and electrochemical emission spectroscopy (EES) using the asymmetrical arrangement replacing the second working electrode for a platinum micro-cathode. The statistical method, fast Fourier transform, and discrete wavelet transform were used for analyzing the potential and current signals recorded by both arrangements. The results showed that EN arrangement was more effective to detect the crack initiation at a point close to yield strength despite stress-induced asymmetry in one of the electrodes. For the EES arrangement, the micro-cathode had a strong influence on the electrochemical noise of the current and potential under stress conditions. From the transient features, statistical parameters, and wavelet analysis, a discontinuous transgranular SCC mechanism was found. The resistance values obtained by EN measurements had better correlation with the electrochemical impedance spectroscopy results (EIS) than EES measurements.

In this research the electrochemical performance of a high strength low alloy steel (HSLA) in contact with a brine solution containing a filmic inhibitor was studied. The API X100 steel was obtained through a casting of steel followed by a rolling process. The steel was microstructurally and mechanically characterized. A multiphasic ferrite-bainite morphology was found, as well as an average hardness of 209 HB after rolling, and using a correlation between Brinell hardness and tensile strength, a resistance of 104,500 Psi was determined. The steel was characterized by Electrochemical Impedance Spectroscopy (EIS) using a brine solution with 50 ppm of corrosion inhibitor like electrolyte. In the electrochemical analysis a capacitive system was obtained, which was influenced by the processes of mass transfer and adsorption, which limited the charge transfer processes. The addition of inhibitor improved the absorption processes by limiting the oxide-reduction processes

This work shows the research about the corrosion mechanism analysis of a X100 pipeline steel immersed in NACE brine under turbulent flow conditions (1000 and 5000 rpm) at room temperature and atmospheric pressure of Veracruz Port. In order to study the hydrodynamic conditions, a rotating cylinder electrode (RCE) was used, while to the electrochemical analysis, the electrochemical techniques like potentiodynamic Polarization Curves (PC) and Linear Polarization Resistance (RPL) were used. The obtained results shown that the corrosion system is limited by the mass transfer process, specifically the oxygen transfer from the bulk to the metallic surface, due to the momentum transfer, called “Convective Diffusion.” It is important to point out that this diffusion can modify the electrochemical reactions (incrementing of redox reactions), so the stability of the corrosion products films adsorbed on metallic surface are dependent to the shear stress and the aggressiveness of the medium.