CIDEPINT   05376
CENTRO DE INVESTIGACIONES EN TECNOLOGIA DE PINTURAS
Unidad Ejecutora - UE
artículos
Título:
Behavior of two eco-compatible duplex systems used in the construction industry against corrosion
Autor/es:
P.R. SERÉ; C.DEYÁ; C.I.ELSNER; A.R.DISARLI
Revista:
INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES
Editorial:
ELSEVIER SCI LTD
Referencias:
Lugar: Amsterdam; Año: 2014 vol. 50 p. 1 - 6
ISSN:
0143-7496
Resumen:
Two typesofcoatedsteelsarecurrentlycompetingintheconstructionindustry:thehot-dipgalvanized steel (HDGS)andthe55%Al?Zn alloycoatedsteel(HDZAS).Bothsystemsaretypicallycoatedbya chromate-basedconversion film, whichisdangerousforhumanhealthandenvironment.Furthermore, for aestheticspurposesand/ortoprolongtheirexpectedorplannedservicelife,theyarepainted designing eachpaintsystemasafunctionoftheserviceconditionstowhichtheywillbesubjectto.The present workreportsonacomparativestudyoftwoduplexsystems:steel/metalcoating/organiccoating. In bothcases,thechromate-basedpretreatmentwasreplacedbyanotheronethatfeatures γ- mercaptopropyltrimethoxysilane(MTMO)asanactiveelement.Theorganiccoatingusedwasawater- based polyurethane.Behaviorofthispaintagainstcorrosionwasassessedbyexposingthesamplesinsalt sprayorhumiditychambers,andmonitoringitsevolutionbyelectrochemicalimpedancespectroscopy, visual observation,scanningelectronmicroscopyandenergydispersiveX-rayanalysis.Theresults revealedthat:MTMOwassuitableforpromotingadhesionbothinHDGSandHDZAS;inhumidity chamber,bothduplexsystemsprovidedgoodprotection;thepresenceofcorrosionproductsofthebase steel andpaintblisteringwasdetectedintheHDGS/paintsystemseventy-twodaysafterexposure; however,150daysafterthat,noneoftheseeffectswereobservedintheHDZAS/paintsystem;differences in behaviorweresignificant inSaltspraychamber:speedofpaintdelaminationfromthemarkdoneand the bulkofcorrosionproductsgeneratedwasmuchhigherinHDGS/paintsystemthaninHDZAS/paint.