Effect of different homogenization treatments on the hot workability of aluminium alloy AA2024

Abstract

Hot-torsion tests have been carried out on samples of an aluminium alloy AA 2024 homogenized at 460 or 500 °C for 8 or 24 h followed by a water quench. The tests have been carried out with strain rates between 0.1 and 10 s −1 at 340, 370 and 400 °C. The peak stress, the softening during torsion and the apparent activation energy are higher but the ductility is lower for the samples homogenized at 500 °C than for those treated at 460 °C. The increases in peak stress and softening and the decrease in ductility with increasing homogenization temperature is more pronounced at low than at high test temperatures. An increase in the homogenization time from 8 to 24 h has almost no effect on the values of peak stress and softening but improves the ductility owing to particle solution. The effects are discussed in terms of solid solution hardening and dynamic precipitation.