| Abstract Scope |
The 5xxx series Al–Mg alloys have a high strength-to-weight ratio, excellent weldability, and superior corrosion resistance, positioning them as a promising alternative to steel for structural applications in the marine industry, thereby enhancing overall fuel efficiency. However, high magnesium content (>3 wt.%) can lead to sensitization at relatively low temperatures. This occurs due to the formation of the electrochemically active Mg-rich β (Al3Mg2) phase, which precipitates at grain boundaries and can cause stress corrosion cracking. In this study, Al-5059-alloy plates were subjected to friction stir welding at various rotational speeds of 1130, 1530, and 1930 rpm, followed by sensitization at 60 °C for 75 days. Immersion tests, intergranular corrosion (IGC) tests, and electrochemical testing were conducted on both sensitized and unsensitized samples from different welding zones. Additionally, stress corrosion cracking tests were performed, and the results were correlated with the microstructure to identify which zones are more susceptible to failure. |