Effectiveness of 2‐mercaptobenzothiazole, 8‐hydroxyquinoline and benzotriazole as corrosion inhibitors on AA 2024‐T3 assessed by electrochemical methods

Abstract

In this study, the effectiveness of 2-mercaptobenzothiazole (2-MBT), 8-hydroxyquinoline and benzotriazole as corrosion inhibitors for AA 2024-T3 aluminium alloy was evaluated. The corrosion behaviour in the presence of each compound was investigated by image-assisted electrochemical noise analysis, electrochemical impedance spectroscopy, potentiodynamic polarization and the split cell technique. It was found that 2-MBT has superior inhibition properties compared with the other inhibitors. In particular, the specimens immersed in 3.5% NaCl in the presence of 2-MBT displayed high values of noise resistance that were maintained for over 400 h of testing, and high values of low-frequency impedance, measured after immersion for 24 h. The split cell technique and potentiodynamic polarization tests indicated that only 2-MBT decreases significantly both the anodic and the cathodic reaction rates. Scanning electron microscopy observations and energy dispersive X-ray measurements complement the findings from electrochemical measurements indicating that only 2-MBT protects the second phase particles, preventing dealloying, trenching and initiation of corrosion.

Development of a Chromium-Free Post-Anodizing Treatment Based on 2-Mercaptobenzothiazole for Corrosion Protection of AA2024T3

“…Boisier et al used post treatment to the anodizing process based on carboxylic acids before hot water sealing and achieved improved corrosion resistance on aluminum alloy. 26 Balaskas et al 27 also investigated 2-MBT as a corrosion inhibitor for AA2024T3, showing that the presence of inhibitor in the aggressive environment effectively prevents corrosion initiation and propagation for hundreds of hours.…”

“…25 The results show that 2-MBT can significantly decrease the corrosion rate of the anodic reaction by forming a protective layer on the aluminum surface, as well as reducing the corrosion rate of cathodic reactions by restraining copper dissolution and dealloying of the intermetallic particles. Boisier et al used post treatment to the anodizing process based on carboxylic acids before hot water sealing and achieved improved corrosion resistance on aluminum alloy.26 Balaskas et al 27 also investigated 2-MBT as a corrosion inhibitor for AA2024T3, showing that the presence of inhibitor in the aggressive environment effectively prevents corrosion initiation and propagation for hundreds of hours.The aim of this work is to investigate new methods of improving the corrosion resistance of anodized aluminum alloys that are based on the use of 2-MBT and to reduce the energy demand associated with the surface treatment. The new treatment methods involve a post treatment in an ethanol solution of 2-MBT, with or without subsequent hydrothermal sealing.…”

“…26 Balaskas et al 27 also investigated 2-MBT as a corrosion inhibitor for AA2024T3, showing that the presence of inhibitor in the aggressive environment effectively prevents corrosion initiation and propagation for hundreds of hours.…”

Incorporation of silica nanocontainers and its impact on a waterborne polyurethane coating

“…Further development of this study could be an adaptation to aluminum alloys substrates since a lower amount of MBT is generally required to observed efficient protection on this kind of substrate. Encapsulation of molecules with the same solubility parameters as 2‐MBT could also be used to confer other properties such as corrosion detection . These improvements are currently developed in our project framework.…”

8-Hydroxyquinoline complexes (Alq3) on Al(111): atomic scale structure, energetics and charge distribution

“…It leads to a strong bonding between the Al atom and the q molecules. As experimental works proposed that q complexes are present on aluminium surfaces during the corrosion inhibition process by 8Hq molecules [9][10][11][12][13] , the adsorption of complexes on the Al(111) surface was investigated and the results are presented in the following. First, the deposition on Al(111) of an Alq 3 complex previously formed in vacuum was studied.…”