Mechanical properties of rolled and aged AA6061 sheets at room-temperature and cryogenic environments

Abstract We prepared AA6061 sheets by room-temperature rolling and low-temperature aging. We tested the tensile mechanical properties of the sheets at room temperature and cryogenic (173 K) temperature. The maximum difference between the cryogenic ultimate tensile strength and room-temperature ultimate tensile strength was 50 MPa for the sheets subjected to a rolling reduction ratio of 50% and aging at 393 K for 10 h. As the rolling reduction ratio increased, the lattice friction stress, dislocation strengthening, and precipitation strengthening of the material gradually approached a limiting value, thus reducing the difference between the strengths of the samples tensile tested at room temperature and cryogenic temperature.