2024 T-351 Aluminium is an aluminium alloy with copper and magnesium as the alloying elements. It is used in applications requiring a high strength to weight ratio, as well as good fatigue resistance. Welding by any means is NOT recommended for this alloy because of the degradation of corrosion resistance that occurs as a result of weld heat. 2024 Aluminum has good to average machinability. Due to its high strength and fatigue resistance, 2024 is widely used in aircraft structures, especially wing and fuselage structures under tension.