Deformation scheme and preheat treatment of Al-4.1%Cu-1.4%Mg aluminum alloy are chosen, homogenizing annealing at 430°C for 1.5？h, cooling to 250°C in furnace at a cooling rate of less than 30°C/h and then cooling to room temperature to make Al-4.1%Cu-1.4%Mg aluminum alloy annealed fully. Heat treatment tests of Al-4.1%Cu-1.4%Mg aluminum alloy mainly consisting of rolling and aging were conducted, and the optimum peak of aging mechanism is 190°C/12？h. Through comparison of microstructure and mechanical properties with different deformation rates and aging mechanisms, effect of deformation rates and aging mechanism on properties of Al-4.1%Cu-1.4%Mg aluminum alloy was analyzed, and the optimum double peak of aging mechanism is 135°C/7？h？+？185°C/14？h. Orthogonal experiments were carried out to analyze mechanical and electrical properties of tested materials before and after deformation, and the effect of aging mechanism on Al-4.1%Cu-1.4%Mg Al alloy was analyzed, and the optimum regression of aging mechanism is 190°C/12？h？+？240°C/40？min？+？190°C/12？h. Aging scheme is closely related to corrosion resistance of Al-4.1%Cu-1.4%Mg aluminum alloy, and three different aging schemes can improve the corrosion resistance. The exfoliation corrosion evaluation results show that the aging effect on exfoliation corrosion ability order is RRA two-step aging peak aging. 1. Introduction After a combination of solution treatment and aging, Al-Cu-Mg aluminum alloy possesses high strength, which makes it a most widely used aluminum alloy [1]. As a duralumin, Al-Cu-Mg aluminum alloy has a good molding ability and mechanical processing properties. Al-Cu-Mg aluminum alloy products mainly consist of plates, wires, and bars, which are mainly developed for the aircraft skin, bulkheads, wing ribs, engine components, and automobile industries [2, 3]. In order to develop aluminum alloy with high strength, high toughness, and high resistance to stress corrosion cracking, many trials and studies were carried out for decades, and there are mainly two effective methods, thermomechanical treatment (TMT) and retrogression and reaging (RRA) [4, 5]. TMT is a process combining both strain hardening after the plastic deformation and phase transformation strengthening after heat treatment [6]. The basic principle is to increase the density of defects in the metal deformation and change its distribution; deformation defects generated by phase transition during heat treatment will affect nucleation and distribution of the new phases; at the same time, the formation of new phases will pin or block
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