Titre : |
Improvement of barrier properties of Cr-free pretreatments for coil-coated products |
Type de document : |
texte imprimé |
Auteurs : |
Ville Saarimaa, Auteur ; Antti Markkula, Auteur ; Jyrki Juhanoja, Auteur ; Bengt-Johan Skrifvars, Auteur |
Année de publication : |
2015 |
Article en page(s) : |
p. 721-730 |
Note générale : |
Bibliogr. |
Langues : |
Américain (ame) |
Catégories : |
Coil coatings Laque et laquage Matériaux -- Propriétés barrières Peinture sur panneau Résistance à l'humidité
|
Index. décimale : |
667.9 Revêtements et enduits |
Résumé : |
Humidity resistance of pretreated and coil-coated panels was evaluated with a special emphasis on the process parameters that govern the uniformity and barrier properties of hexafluorotitanic acid-based pretreatment layers. Humidity resistance tests showed that good barrier effect was obtained with pretreatments in the coating weight range of about 2–17 mg Ti/m2. It was further verified by rinsing experiments that a fully reacted pretreatment layer is achieved at the very low end of the optimal coating weight range. Increasing the coating weight leads to the formation of precipitated, loosely bonded porous structure, which was detrimental to humidity resistance. In addition to the coating weight, the microscale pretreatment layer uniformity is of utmost importance for good barrier properties. Electron probe microanalysis measurements provide an efficient tool to assess the pretreatment layer uniformity and facilitate monitoring of process adjustments with clear correlation to humidity resistance properties of painted panels. The surface condition of the hot dip-galvanized steel and the material of the application rolls were found to strongly affect the uniformity of the pretreatment layers. |
Note de contenu : |
- EXPERIMENTAL : Materials - Sample preparation - Surface characterization - Humidity resistance testing
- RESULTS AND DISCUSSION : Influence of pretreatment coating weight on humidity resistance of painted panels - Evaluation of pretreatment layer retention - SEM imaging of pretreated samples - Influence of surface cleaning on pretreatment layer formation - Influence of roll material and pressure on pretreatment layer formation |
DOI : |
10.1007/s11998-015-9663-6 |
En ligne : |
https://link.springer.com/content/pdf/10.1007%2Fs11998-015-9663-6.pdf |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=24406 |
in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 12, N° 4 (07/2015) . - p. 721-730