[article]
Titre : |
Prepare hot-dip galvanized coating surfaces for painting |
Type de document : |
texte imprimé |
Auteurs : |
Thomas J. Langill, Auteur |
Année de publication : |
2016 |
Article en page(s) : |
p. 24-33 |
Note générale : |
Bibliogr. |
Langues : |
Américain (ame) |
Catégories : |
Acier L'acier est un alliage métallique utilisé dans les domaines de la construction métallique et de la construction mécanique.
L'acier est constitué d'au moins deux éléments, le fer, très majoritaire, et le carbone, dans des proportions comprises entre 0,02 % et 2 % en masse1.
C'est essentiellement la teneur en carbone qui confère à l'alliage les propriétés du métal qu'on appelle "acier". Il existe d’autres métaux à base de fer qui ne sont pas des aciers comme les fontes et les ferronickels par exemple. Galvanisation Métaux -- Revêtements protecteurs Passivité (Chimie) Phosphate de zinc Polyacryliques Primaire (revêtement) Surfaces -- Nettoyage Traîtements de surface
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Index. décimale : |
667.9 Revêtements et enduits |
Résumé : |
Hot-dip galvanized steel parts or assemblies are often required to be painted, either to identify a structure, for architectural reasons, to provide a particular type of protection, to prevent severe corrosion attack of zinc in an acidic environment, or to extend the service life of an existing structure. The combination of a paint system with a hot-dip galvanized coating is referred to as a duplex system'. When paint and galvanized steel are used together, the corrosion protection is superior to either protection system used alone.
The application of a paint system onto a hot-dip galvanized surface requires careful surface preparation and a good understanding of both corrosion protection systems. The margin for error is small when dealing with newly galvanized steel surface preparation. However, there have been many exemples of paint adhesion problems on older or more moderately aged galvanized steel surfaces, and the most commun cause is improper or incomplete surface cleaning and preparation.
The adhesion of paint onto galvanized steel can become a small problem when the galvanized coating has weathered for at least a one-year period. The zinc corrosion products form a very dense, insoluble protective layer that accepts a paint coat readily. A brand new galvanized coating also experiences few adhesion problems within the first 24-to-48 hours after coating. Although these two conditions can yield a sustainable duplex system, the must common timing for applying paint onto a galvanized part is between 2 deys and 6 months after galvanizing, where there can be many preparation issues to be handled in order to obtain an intact duplex system. |
Note de contenu : |
- Galvanized coating application
- Galvanized coating surface
- Surface preparation : surface cleaning - surface profiling - penetrating sealers - zinc phosphate treatment - wash primers - acrylic passivation
- Paint selection |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=25421 |
in JOURNAL OF PROTECTIVE COATINGS & LININGS (JPCL) > Vol. 33, N° 1 (01/2016) . - p. 24-33
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