This paper is focused on the fatigue behaviour of aluminium alloy welded joints, which can represent points of weakness in the ship structure. The traditional methods of fatigue assessment of welded joints have some limitations, and are extremely time consuming. In order to overcome these difficulties, the Risitano's method, based on thermographic analysis, has been applied to predict the fatigue behaviour of welds. Experimental tests have been carried out to assess and compare the fatigue capability (S-N curves, endurance limits) of different welded joints, obtained by means of Friction Stir Welding (FSW) and Metal Inert Gas welding (MIG). Fatigue predictions obtained resorting to the Thermographic Method (TM) show a good agreement with those derived from the traditional procedure. Thus, TM proves to be a powerful tool also for the characterization of the mentioned kind of welded joints.
