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Investigation of the impact resistance of Al-Zn-Mg-Cu alloys as aerospace materials is of great significance to expanding its extreme applications in engineering.In this paper, taking 7A04-T6 as the specimen material, the experimental study of dynamic mechanical response of materials at different temperatures and strain rates is carried out withthe split Hopkinson pressure bar device.The results show that,undertheexperimental temperature within 25℃-150℃, the thermal softening effect in the high-speed impacted material takes advantage of the competition with the work hardening, resulting in the decrease of the material"s flow stress. With the increase of average strain rate, both the flow stress and the yield strength of the material increase, which indicates an obviousstrain rate hardening effect.Adiabatic shear phenomenon can occur in the material under high-speed impacting, accompanied by macroscopic cracks. When the adiabatic temperature rise is superimposed on the experimental temperature, it fulfills the solid dissolution condition for the reinforcementphases in local adiabatic shear bands, and the fracture failure of the material occurs when it is much lower than the phase transition temperature.