Estudo da corrosão dos aços inoxidáveis austeníticos e super austeníticos em água de poço de petróleo com e sem CO2

Abstract

The pre-salt region is very hostile to the materials used there due to some factors found under the pre-salt layer such as: corrosive gases, oil formation water, high pressures and so on. The corrosion resistance of austenitic and super austenitic stainless steels in artificial oil field formation water was tested in two environments and using two electrochemical techniques. The first environment used was an aqueous solution of artificial oil field formation water saturated with CO2. The electrochemical technique used in this test was potentiodynamic polarization. The other medium used was only artificial oil filed formation water without the presence of CO2, aiming to evaluate only the effect of the solution on the corrosion resistance of the studied alloys. For this test, a potentiostatic electrochemical technique called potential step was used. The results showed that, in the presence of CO2, the corrosion on the surface of conventional authentic steels, mainly 316L, was more severe. The type of corrosion found was pitting corrosion. The super austenitic steels studied in this research, on the other hand, were resistant to pitting corrosion in the two media used. No pits were found on their surfaces.