Effect of corrosion exposure on the mechanical performance of aeronautical aluminum alloy 2024 riveted sheets

The effect of corrosion exposure on the tensile mechanical properties of aeronautical aluminum alloy 2024-T3 with the presence of holes for their subsequent connection with rivets as well as the corrosion mechanism is investigated. Three different experimental series were performed for the simulation of corrosion attack on aircraft structures. The first experimental series included the investigation of corrosion mechanism for the specimens exposed for different times to EXCO solution on all their surfaces, including the interior of the hole. The second experimental series included the specimens corroded only within the hole, while the third experimental series consisted of the specimens that were exposed only on the surfaces outside the hole. The separation in the above-mentioned experimental series was carried out to simulate the case of damage on the aircraft’s anti-corrosion coating at points of joining of their structural parts. According to the results of the present work, it was found that corrosion affects the different surfaces of the material in a different way, with the specimens corroded inside the hole exhibiting greater corrosion susceptibility (or less corrosion resistance) and the interior of the hole (through thickness area) to play a key contributing role in the total reduction of elongation at fracture Αf, due to the ease of corrosion penetration between the highly elongated grains in this area.