Solvent-based acrylic carbon paint anodes were installed on the north approach spans of the Yaquina Bay Bridge (Newport OR) in 1985 and performed well after 15 years. Anodes were inexpensive and repairs easy. Depolarization potentials are consistently above 100 with long-term current densities around 2 mA/m 2. Bond strength remains adequate.
Galvele introduced a new framework for localized corrosion with his seminal paper on acidification and chloride accumulation in pits & the need for a critical product of current density & pit depth to sustain this chemistry. This paper is to review the progress in these areas with a particular focus on repassivation potential.
Hydrogen Induced Cracking (HIC) can be a major issue for line pipe exposed to sour environments. In this study, influence of the test solutions on HIC evaluation was investigated from the view point of corrosion. Electrochemical measurements were employed to compare corrosion behavior of line pipe steels between the 0.93N acetate buffer solution and the conventional 0.05N acetate solution.
Over 5 years, 70 to 80 FGD scrubber units have exhibited corrosion problems. Many were after only a few months of service. This paper will provide an overview of readily available technical information in the published literature and past experience that could have been used to minimize corrosion problems in these FGD units.
The work is mainly focused on the corrosion mechanism at low pH (>4) and the order of which the discontinuous and continuous intermetallic phases dissolve. Compositions of each phase, and the area ratio between intermetallic phases and the alpha matrix have been calculated as an average of 20 measurements.