The electrochemical behavior of A516 grade 70 (UNS K02700) carbon steel with a ferrite-pearlite structure in acidic chloride (Cl(-)) solutions containing hydrogen sulfide (H2S) at 25 deg C was investigated by electrochemical impedance spectroscopy (EIS). Results showed the impedance of A516 steel increased in an acid Cl(-) solution with H2S (compared to a solution without H2S) at the open circuit potential (OCP). The corrosion process for A516 steel in the H2S-containing solution was in two stages. Polarization resistance (Rp) initially increased with the time for immersion up to ca. 10 h but then decraesed gradually. In the early stage, the impedance was characterized by one large semicircle in the Nyquist plot that increased with time for immersion up to 3 h. In the later stage, precipitation of a sulfide film modified the surface properties and led to variation in EIS data through a capacitive effect in the low-frequency region.
Electrochemical behavior of A516 carbon steel in solutions containing hydrogen sulfide
Elektrochemisches Verhalten des Kohlenstoffstahls A516 in schwefelwasserstoffhaltigen Lösungen
Corrosion, Houston ; 52 , 9 ; 708-713
1996
6 Seiten, 7 Bilder, 21 Quellen
Aufsatz (Zeitschrift)
Englisch
Corrosion behavior of carbon steel in bicarbonate (HCO3(-)) solutions
Tema Archiv | 2002
|