Recovery and strain-hardening of AlMg alloys

The recovery of AlMg alloys cold-rolled to several strains between 0.1 and 3 has been studied by tensile tests. The study is based on the determination of the tensile strain-hardening properties at constant strain-rate, as a function of the initial prestrain and of the static recovery temperature and duration. A modeling of the tensile curves is performed through plastic strain constitutive equations where are taken into account at a mesoscopic scale dislocation storage and dislocation annihilation. It is shown that prestrain and static recovery effects may be analysed in terms of modifications of the storage and dynamic recovery parameters involved in the strain-hardening rate. These modifications are in agreement with electron microscopy observations of the microstructure.