Effect of Microalloying on Hot Deformation Behavior of 8021 Aluminum Alloy

A comparative study of the hot deformation of the aluminum (8021) alloy with and without Sr addition under the conditions of deformation temperature of 350–500°C and strain rate of 0.01–10 s^–1 has been performed. The effect of adding 0.4% Sr on the microstructure of the alloy was investigated by EBSD and TEM, and the constitutive equations for the 8021 aluminum alloy with and without Sr were established. The results show that the hot activation energy decreases from 225.69 to 217.72 kJ/mol with the addition of 0.4% Sr to the alloy, which expands the safe processing range of the 8021 aluminum alloy. Compared with the alloy without Sr, the alloy with 0.4% Sr has a lower ln(Z) value. Adding Sr to the alloy decreases the density of dislocations, and it promotes the occurrence of dynamic recrystallization in the alloy, with an increase in the number of subgrains. The hot deformation behavior of the 8021 aluminum alloy is important for optimizing the alloy’s processing parameters and provides a reference for the industrial application of the 8021 aluminum alloy.