The scanning microreference electrode (SMRE) technique was used to study the early stage of pitting corrosion of 18/8 stainless steel (SS) in solutions containing chloride (Cl-) ions. Local breakdown of passivity and micropitting corrosion occurred in the potential region that was much more negative than the ordinary pitting potential (Ep). A critical potential (Er) was measured by imaging the potential near the metal surface in solution to characterize the local rupture of passivity or micropitting initiation. The concept of metastable micropitting was adopted to discuss the mechanism of pitting corrosion in its early stage.

Subject
Pits, Anode potential, Metal surfaces, Passive films, Imaging, Corrosion initiation, Acidity, Sodium chloride solution, Ion concentrations, Negative potentials, Pitting, Passivity, Electrode potential
Keywords:
18/8 stainless steel, chloride, micropitting, passivity, pitting corrosion, pitting potential, scanning microreference electrode, type 304 stainless steel
NACE International
1998
You do not currently have access to this content.