Article ID Journal Published Year Pages File Type
1470695 Corrosion Science 2011 11 Pages PDF
Abstract

The role of metallic microstructure in 0.5 μl seawater droplet corrosion of aluminium alloy 2024 (AA2024) has been investigated. Focussed ion beam/scanning electron microscopy (FIB/SEM) was used to determine the relationships between the corrosion products formed at specific sites at the surface and the underlying attack mechanisms. Dealloying of S-phase particles, matrix/particle interfacial attack and grain boundary attack were the predominant attack modes. Cooperative behaviour between IM particles was made possible by networks of etched grain boundaries, which provided a connecting path.

Research highlights► Microstructure dictates attack site distribution on AA2024 under a seawater drop. ► S-phase dealloying was influenced by geometry and crystallography. ► Matrix dissolution adjacent to S-phase went simultaneously with S-phase dealloying. ► S-phase/matrix interfacial attack followed an acid dissolution model. ► Cooperative attack on intermetallic particles linked by grain boundary networks.

Related Topics
Physical Sciences and Engineering Materials Science Ceramics and Composites
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