Effect of thermo-mechanical treatments on dynamic deformation behaviors of 2519A aluminum alloy

Abstract

The dynamic deformation behaviors of 2519A aluminum alloy treated by T87, T8, T9 and T9I6 were investigated by the split Hopkinson pressure bar in the strain rate range of 1040-5900 s-1, and the microstructure evolution of the alloys during high velocity impact were analyzed by means of metallography and transmission electron microscopy, the effect of different thermo-mechanical treatments on dynamic responses of aluminum alloy 2519A was revealed. The results show that the dynamic yield strength of 2519A-T8 or T9 aluminum alloy is increased significantly than T87 treated alloy, but the adiabatic shear susceptibility is dramatically improved. Interrupted aging T9I6 can improve θ' (Al2Cu) precipitates density and make them much finer and denser, which reduce the decomposition rate of θ' precipitates and enhance its stability at high strain rate. So 2519A-T9I6 aluminum alloy has much higher dynamic yield strength, and lower adiabatic shear susceptibility, which shows best performance at high strain rate.

Keywords

• 2519a aluminum alloy
• thermo-mechanical treatment
• high strain rate
• dynamic yield strength
• adiabatic shear susceptibility
• θ' precipitate