On the Localised Corrosion of Aa5083-H111 Using a Simulated Dynamic Seawater/Air Interface

Abstract

This study investigated the localised corrosion of aluminium alloy AA5083-H111 using a simulated dynamic seawater/air interfacial zone. Testing also included electrochemical impedance spectroscopy and electrochemical noise. Insights into the role of Al-Fe/Ti intermetallic particles (IMPs) on localised corrosion were revealed by focused ion beam, transmission electron microscopy and energy dispersive x-ray spectroscopy. As compared with the full immersion zone, the interfacial zone showed higher polarisation resistance and lower effective capacitance, which was attributed to the high oxygen extent in the interfacial zone. Localised corrosion was observed arising from the IMPs including the Al-Fe phase and Ti enriched phase.

Keywords: AA5083, localised corrosion, dynamic seawater/air interface, electrochemical noise, TEM.