CO2-saturated NaCl Solution Research Articles

Effect of Cl<sup>-</sup> Content, pH Value and CO<sub>2</sub> on Electrochemical Corrosion Features of Cr15 Super Martensitic Stainless Steel

The corrosion behavior of a Cr15 super martensitic stainless steel (Cr15 SMSS) was investigated in NaCl solutions by means of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Effects of Cl-content, pH value and saturated CO2on corrosion were sdudied. It was found that the parameters of maintaining passivity current density (ip), the critical pitting potential (Eb) and charge transfer resistance (Rt) of Cr15 SMSS varied widely under different conditions. The corrosion resistance of Cr15 SMSS decrease with increasing Cl-concentration and lowering pH value. BothipandEbincrease for Cr15 SMSS in CO2-saturated NaCl solution, which verified that the CO2in NaCl solution can result in lower pitting sensitivity and higher uniform corrosion rate to Cr15 SMSS.

Effect of Flow and a Triazole Derivative Based Inhibitor on the Corrosion of API X52 Pipeline Steel Grade in CO2 Saturated Brine Solution

The effect of moving environments on the efficiency of corrosion inhibitors is a research topic that has been in continuous development over the recent years. The present work explores the effect of turbulent flow on the electrochemical behavior and efficiency of a triazole-based corrosion inhibitor (3-amino-1,2,4, triazole, aminotriazole or 3-AT) in a CO2 saturated NaCl solution, using the rotating cylinder electrode, RCE, as hydrodynamic control system. The influence of turbulent flow on the corrosion rate of X52 pipeline steel was investigated using polarization curves and polarization resistance, Rp, techniques. It was found that the inhibiting effect of the triazole is considerably increased by flow.