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Purpose -The application of coatings on metal substrates can provide an increase in corrosion resistance in the environment where the material is employed. The use of silane causes low environmental impact and may represent an alternative to replace chromates and phosphates applied as a pretreatment prior to surface painting. The objective of this study was to evaluate experimental parameters for the investigation of the formation of a vinyltrimethoxysilane (VTMOS) monolayer on 1010 carbon steel applying electrochemical techniques. Design/methodology/approach -A total of 24 types of coated samples were obtained, following three 2 3 factorial design of experiments (DOE), and one uncoated. The VTMOS monolayer was formed by hand dip process, followed by curing in a stove, using substrates of sanded, pickled and degreased 1010 carbon steel and hydrolyzed silane. Findings -The results of coated samples were satisfactory as compared to those of uncoated carbon steel, as the former were better protected against corrosion. Originality/value -This paper shows an evaluation of experimental parameters that influence the formation of a film of silane VTMOS on 1010 carbon steel by means of electrochemical techniques. The results indicated that the silane monolayer VTMOS promotes enhanced properties that prevent corrosion of 1010 carbon steel and the method of film formation directly influences the properties of such protection.

In this work, the wettability of the galvannealed surface pretreated with the hybrid silane APTES/GPTMS film was measured by sessile drop method. The coatings were applied on the substrate from dip-coating method and dried in an oven. The study followed an experimental factorial design, 3³, with contact angle as response. The corrosion resistance was evaluated by electrochemical techniques and the surface morphology was characterized by scanning electron microscopy. The wettability results showed the best condition for galvannealed steel pretreated with the hybrid silane film for 2:1 APTES:GPTMS ratio, 2% silane concentration and 150 min of hydrolysis time, because the result may be related to a higher rate of hydrolysis of the silanes that is influenced by both the functional group present and by the type and number of hydrolyzed groups, resulting consequently in a higher availability of silanol groups in solution, promoting a greater crosslinking of the film on the metallic substrate.