Inhibition of localized corrosion as determined by a galvanodynamic method

• Published in: Journal of the Electrochemical Society 1984-08, Vol.131 (8), p.1844-1846
• Main Authors: VIEHBECK, A, DEBERRY, D. W
• Format: Article
• Language: English
• Subjects: Applied sciences; Corrosion; Corrosion prevention; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Metals, semimetals and alloys; Metals. Metallurgy; Physics; Specific materials
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1.2115973

The inhibition of pitting on 304L stainless steel by a surface active chelating agent (N-lauroylsarcosine or NLS) in aqueous solutions containing chloride ions is described. A galvanodynamic method was developed for study of this system and appears to have attractive features for the study of pitting corrosion in general. The results indicate that NLS inhibits the breakdown of passivity and perhaps aids repassivation of incipient pits. However, once breakdown has occurred to a certain stage, pits can continue to propagate in the presence of NLS. The results also indicate that the organic compound influences the interfacial processes in such a way that the electrode can sustain a higher charge density before localized breakdown of passivity takes place. The presence of NLS also appears to significantly increase the noise associated with the E sub b plateau, perhaps indicating that it continues to interfere with pit nucleation and propagation, even after the initial breakdown.--S.K.B.