Microcell electrochemical technique in seawater applied on dissimilar joints of aluminum alloy and carbon steel obtained by friction stir welding

Over the past twenty years, friction-welding technology, in particular the Friction Stir Welding (FSW) has become a potential industrial welding method that has been used efficiently for combining similar and dissimilar materials. The latter solution is very interesting in ship-building, where the use of aluminum in the superstructures allows lowering of the center of gravity for a better stability of the ship. In making dissimilar joints, the FSW technique is more cost and time efficient, allows to weld various sheet thickness with different joint configurations. In this work a coupled mechanical, metallurgical and electrochemical characterizations of dissimilar joints of aluminum alloy AW5083 and carbon steel S355 obtained by butt joint welding (FSW) were performed. The results showed that during the FSW process several well-defined microstructural zones are generated, that affected the mechanical performances and the corrosion behavior of the weld.