Effect on temporary protection and adhesion promoter of silane nanofilms applied on electro-galvanized steel

P.R. SERÉ; M. BANERA; W. EGLI; C.I. ELSNER; A.R. DI SARLI; C. DEYA

INTERNATIONAL JOURNAL OF ADHESION AND ADHESIVES

ELSEVIER SCI LTD

Lugar: Amsterdam; Año: 2016 vol. 65 p. 88 - 95

0143-7496

In this paper, the effectivenessof γ-mercaptopropyl trimethoxysilane (MTMO) films as temporary corrosionprotection and adhesion promoter on electro-galvanized steel was studied. The filmsweresyn- thesized from hydrolyzed MTMO with ethanol or methanol, applied by immersionon electro-galvanized steel and cured under different conditions. The porosity ofthe coating was evaluated by cyclic voltammetry, the corrosion behavior by polarizationcurves and the protection degree by exposure in the humidity and prohesion chambers.The filmswere characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy(EDS). From the obtained experimental results, it was concluded that thisprotection is markedly affected by the coating curing conditions and the alcoholused in the hydrolysis. MTMO is a good temporary protector against electro-galvanizedsteel corrosion in high humidity environment but it is less effective in environmentscontaining aggressive ions such as Cl- and SO4_2.In a second stage, pretreated samples were coated with an alkyd anticorrosive paintand exposed to the salt spray chamber. Dry adhesion tests as well as SEM and EDSstudies were also done in order to know the nature of the disbanding fails (adhesionor cohesion).