The corrosion behavior of the 6061 Al alloy in simulated Nansha marine atmosphere

Abstract

The corrosion behavior of the extruded 6061 Al alloy within 40 days of exposure in simulated Nansha marine atmosphere is investigated by electrochemical measurements, microscopic observations and X-ray photoelectron spectroscopy (XPS) tests. It is found that severe intergranular corrosion (IGC) and intragranular corrosion occur on the sample surface. Mg2Si phase and AlFeSi particles are the main intermetallic compounds in the 6061 Al alloy, which are closely related to the initiation and propagation of IGC. Moreover, the preferential dissolution of Mg from Mg2Si phase is observed and the reasons are explained from the perspective of thermodynamics. This study provides some valuable information for comprehensive understanding the corrosion behavior and mechanism of the 6061 Al alloy in simulated Nansha marine atmosphere. It is anticipated that we can use this valuable information to develop and design new Al alloys to make them more resistant to corrosion in this environment in the future.