Abstract
In the present paper the deformation behaviour of AA2024 aluminium alloy has been studied through double-hit compression testing in the temperature range of 350-400 °C. The initial strain rate was 0.1 s^-1 and the second pass strain rates of 0.0001, 0.001 and 0.01 s^-1 have also been tested. The results indicate that at high temperature and low strain rates, dynamic recrystallization has occurred during the second pass straining. Moreover, the flow stress is reduced by decrease of the strain rate during the hot work hardening (i.e., dynamic work softening) and in this case it is attributed to both the restoration process and particles coarsening during straining. In addition, this may be assisted by particles precipitation and their subsequent dynamic growth.

Key words
Dynamic recovery, work softening, work hardening, dynamic precipitation

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