Abstract
Organic-Inorganic hybrid (OIH) derived by sol-gel process have emerged as promising pretreatments alternative to conventional chromate-based systems for aluminum alloys.In this study novel organo-silane precursor has been synthesized from epoxy resin and amino-silane compound and used as the primary component of OIH film. The effects of epoxy and silane functionality and organic inhibitor used in the composition have been studied on corrosion resistance performance of aluminum alloy (3003-H14). The study also investigates the performance of top coat (powder coating) adhesion onto the pretreatment under different cure conditions. The chemical structure of sol-gel precursor (epoxy silane) and the deposited films have been characterized by FTIR analysis. The corrosion protection performance has been studied by electrochemical impedance spectroscopy (EIS), D.C. electrochemical polarization measurements, and the accelerated neutral salt spray test (ASTM B117). This study shows that by proper choice of precursor structure, functionality, processing conditions, and corrosion inhibitor amount, it is possible to derive OIH films with corrosion resistance performance comparable to conventional Cr (VI) based pretreatments.
Highlights
Aluminum alloys are increasingly used as materials of choice for many industrial, automotive and aerospace applications because of their light weight and high strength combined with many desirable mechanical properties
Silane based Organic-Inorganic hybrid (OIH) films were deposited by a two-step acid catalysed sol-gel process
The first step is hydrolysis of GPTMS and epoxy-silane precursor, wherein the majority of alkoxy silane groups are hydrolyzed to silanol groups with formation of corresponding alcohol
Summary
Aluminum alloys are increasingly used as materials of choice for many industrial, automotive and aerospace applications because of their light weight and high strength combined with many desirable mechanical properties. Many aluminum alloys are sensitive to serious corrosion problems when exposed to corrosive environment [1, 2]. It is common practice in industry to use a multi-layer protective coating system for corrosion protection. These multi-layer protective coating systems include a conversion pretreatment that is applied directly on the bare metal surface followed by a primer, and a top coat. The most common and effective pretreatments used in such protective systems is chromatebased conversion coatings (pretreatments) (CCC) [3, 4]. The role of pretreatment is very critical to the success of the entire protective coating system
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
