Temperature-dependent constitutive behavior with consideration of microstructure evolution for as-quenched Al-Cu-Mn alloy

It is difficult to predict the deformation behavior of Al-Cu-Mn alloy during a quenching process due to the complex hardening mechanisms. In this paper, isothermal tensile tests were conducted under controlled experimental conditions (298-773 K and 0.001-0.1/s strain rate). Observations on the microstructure of the alloy and tensile test analyses on stress-strain curves both verified that the deformation mechanisms differed drastically at 298-473 K and 573-773 K. Therefore, a temperature-dependent constitutive model was established to characterize the divergent flow behaviors of as-quenched Al-Cu-Mn alloy. In addition, the activation energy, Q, in the model is determined by the combined effect of dislocation forests and precipitate phases, various with different experimental conditions.