We study welded joints of annealed sheets 6 mm in thickness made of D16M (Al–Cu–Mg) aluminum alloy, which is an analog of the foreign 2024 alloy currently attributed to difficultly welded alloys. The joints are made by the impulsive-arc method with consumable electrode with the use of a Zv1201 (Al–6.3Cu–0.3Mn) filler wire and technological inserts made of 7056 (Al–9.5Zn–1.8Mg–1.6Cu), V96 (Al–8.5Zn–2.6Mg–2.3Cu), and V92 (Al–3.5Zn–4.2Mg–0.5Cu) alloys. We study the regularities of changes in the microstructure, hardness, strength, and cyclic crack growth resistance of the joints after welding and also in the course of subsequent artificial aging or quenching and artificial aging after welding. It is established that the strength of welded joints after thermal treatment does not exceed 68% of strength of the base metal but is comparable with it in the state after welding.