Aluminum alloys are often used due to their low density in the transport industry and elsewhere where low masses are required. Among the most commonly used are wrought alloys from the 2xxx series, such as AA2024-T3. Aluminum alloys have low corrosion resistance which reduces their usability. Due to this it is important to develop corrosion protection that improves the resistance of alloys to corrosion.
In this work we have synthesized a hybrid sol-gel coating for protection of the AA2024-T3 aluminum alloy. The efficiency of the coating has been evaluated in dilute Harrison solution (composition in wt. %: 3.5 (NH$_4$)$_2$SO$_4$ + 0.5 NaCl).
The corrosion coating has been synthesized from poly(bisphenol A-co-epichlorohydrine) (DGEBA), (3-glycidyloxypropyl)trimetoxysylane (GPTMS), diethylenetriamine (DETA), tetrahydrofurane (THF), tetraethyl orthosilicate (TEOS), ethanol and water. Synthesis has been characterized by infrared spectroscopy at individual steps of preparation. The efficiency of corrosion protection has been determined via electrochemistry impedance spectroscopy and salt spray chamber test.
An applied several-micrometer thick protective coating provides long-term (several-month) corrosion protection from the corrosive environment.
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