Room Temperature Recovery Behavior of Cold-Rolled Aluminum Foil Under Severe Plastic Deformation

Pure aluminum foil (dilute Al-Fe-Si alloy series) with Cu or Mn addition was prepared by severe cold-rolling deformation, and the effect of room temperature storage or low temperature annealing on the tensile properties and microstructure was investigated through tensile tests, optical microscope, scanning electron microscope, electron back scatter diffraction, and atom probe microscope. Results show that the ultimate tensile strength and elongation simultaneously decrease after room temperature storage. The recovery mechanism of substructure, such as subgrain coalescence, leads to the decrease in tensile properties. The decrease in plasticity is more significant for the Mn-containing alloy due to the more significantly increased subgrain size. The atom cluster strengthening can compensate for the strength loss to some extent, whereas the effect of the secondary phases is negligible.