Titre : |
Electrochemical impedance spectroscopy evaluation of various aluminum pretreatments painted with epoxy primer |
Type de document : |
texte imprimé |
Auteurs : |
Stephen. M. Cohen, Auteur |
Année de publication : |
1996 |
Article en page(s) : |
p. 73-81 |
Note générale : |
Bibliogr. |
Langues : |
Américain (ame) |
Catégories : |
Alliages Couches minces Diélectriques Epoxydes Matériaux -- Propriétés électriques Métaux -- Oxydation anodique Porosité Primaire (revêtement) Spectroscopie d'impédance électrochimique Traîtements de surface
|
Index. décimale : |
667.9 Revêtements et enduits |
Résumé : |
Panels of aerospace aluminum (Al) alloys 2024 (UNS A92024) and 7075 (UNS A97075) were coated with four pretreatments (thin-film sulfuric-acid [H2SO4] anodization, chromic-acid anodization, and two commercial silica-based gels). Some of these panels were painted with chromated epoxy primer (MIL-P-23377D). All panels were subjected to several months of monitoring by electrochemical impedance spectroscopy (EIS) at open-circuit potential. Several panels were also subjected to EIS measurements made at various applied potentials. Equivalent circuit simulations indicate that a model like that proposed by van Westing, et al., which includes four time-constants (coating, pore, double-layer, and pretreatments) fits the data well. The epoxy primer is shown to be a highly porous, non-barrier coating. |
Note de contenu : |
RESULT AND DISCUSSION : Equivalent circuit used - Dielectric constant and barrier properties of the primer - Dielectric properties of the underlying pretreatment - Measurements under distilled water - Polarization measurements |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=18431 |
in JOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 68, N° 859 (08/1996) . - p. 73-81