Environmentally Friendly Corrosion Inhibition of Sol-Gel Coated Al 2024-T3 Alloy via Inhibitor Pigment Enrichment
Volkan Cicek *
College of Science, Ishik University, Erbil, Iraq
*Author to whom correspondence should be addressed.
Abstract
The corrosion resistance behavior of inhibitor enriched organically-modified silane (Ormosil) thin films on 2024-T3 aluminum alloy substrates were investigated using accelerated salt spray analysis techniques such as ASTM B117. The specified literature composition of the sol-gel mixture was used due to its appropriate inorganic/organic ratio producing a highly adherent film to the underlying AA substrate to be used on Al 2024 alloys on aircrafts. Inhibitors used were synthesized via methods described in author’s previous studies. Several inhibitors, that were initially tested for corrosion inhibition of Aluminum 2024 alloy in aqueous solutions, revealed success when incorporated into the sol-gel coating including chromium borate, chromium oxyhydroxide and chromium octanoate. Certain concentrations of chromium acetate and chromium hydroxide also revealed positive results. With the addition of these inhibitors, corrosion resistance properties of the sol-gel coating increased not only against uniform corrosion demonstrated by the unscribed samples but also against crevice corrosion, that is filiform corrosion, and against pitting corrosion demonstrated by the scribed samples.
Keywords: Sol-gel coatings, ormosils, carcinogenic, inhibitor pigment enrichment, conversion coatings