Development of processing map and constitutive relationship for thermomechanical processing of aluminum alloy AA2014

Isothermal hot compression tests were performed on aluminum alloy 2014 (AA2014) to study the evolution of microstructure over a wide range of temperatures (300°C-500°C) and strain rates (0.001-100 s^-1). The true stress-true strain curves obtained at all deformation temperatures and strain rates showed gradual flow softening, which is typical of a dynamic recovery-type material such as aluminum. Processing maps that delineate the stable and unstable regions during hot working were developed and validated by comparing the microstructures recorded in the deformed specimens. Optimum processing conditions (temperature > 450°C, strain rate < 0.1 s^-1) for the hot deformation of AA2014 were proposed based on contour maps of efficiency of power dissipation and strain-rate sensitivity parameter. The activation energy value (Q<inf>avg</inf>) for the hot working of AA2014 was calculated to be 181 kJ/mol^-1. Finally, the constitutive equation for the hot working of AA2014 was established.