Effects of Solid Solution and Aging Treatment on Microstructure and Dynamic Mechanical Behavior of Extruded 6013 Al Alloy

The effects of solid solution at different temperatures (505-555℃) for 1 h and aging at 180℃ for different times (2-20 h) on the microstructure and dynamic mechanical behavior of the extruded 6013 Al alloy were investigated by Vickers hardness tester, transmission electron microscope and split Hopkinson pressure bar. The results show that with the solid solution temperature increasing, the hardness and true stress of the alloy during dynamic deformation first increased then decreased. After solid solution at 545℃, both the hardness and the true stress were the largest. With the aging time increasing, the hardness and true stress of the alloy also first increased then decreased. After aging for 8 h, the number of needle-like precipitates in the tested alloy was the largest and the precipitates distributed evenly; the hardness and the true stress also reached the largest values; the difference value between true stresses at the true strain of 0.2 under relatively high (5 000 s^-1) and relatively low (2 000 s^-1) strain rates was the largest, showing an obvious strain rate sensitivity.