Surface Engineering Home      Exposition      To Register      ASM Homepage
Back to "Session 20: Aqueous Corrosion" Search
    Back to Main Search

Wednesday, August 4, 2004 - 2:30 PM
SES 20.3

SVET Investigations of Protection Mechanism of Metal-Rich Primers on Al 2024-T3

D. Battocchi, J. He, G. P. Bierwagen, D. E. Tallman, North Dakota State University, Fargo, ND

Metal-rich coatings are studied as an alternative to chromates in paint systems for the achievement of a family of non-toxic coatings. Due to the availability of stable Magnesium particulate, a Mg-rich primer system is under investigation for the protection of Aluminum. Scanning Vibrating Electrode Technique (SVET) is generally used for the investigation of the early stages of corrosion and for the study of localized corrosive processes. SVET investigations are performed on a scribed top coated Mg-rich primer in the vicinity of the scribe. The electrolyte used is a 3% NaCl aqueous solution and the spatial distribution of the current density is evaluated. The analysis of the corrosion processes occurring around a damaged area of such paint system is useful to understand the protection mechanism involved when the metal-rich primer is directly exposed to the electrolyte and can be helpful in future formulation of this type of coatings.

Summary: SVET is generally used for investigations of the early stages of corrosion and for the study of localized corrosive processes. SVET investigations are performed on a scribed top coated Mg-rich primer. The electrolyte used is a 3% NaCl aqueous solution and the spatial distribution of the current density is evaluated.