Influence of artificial aging time on bending characteristics of 6061 aluminum sheet

Abstract6061 aluminum alloy has been widely utilized in modern automobile industries with the advantages of low density, good formability and nice machinability. However, the springback phenomena and cross‐section deformation problems still remain unsolved. Accordingly, the effect of artificial aging time on the aforementioned bending properties of 6061 aluminum sheet at room temperature were investigated based on the three‐point bending test. The mechanical properties of 6061 aluminum alloy was significantly changed by artificial aging treatment, and the bearing capacity of T6‐8 h specimen is 2.11 times that of solution heat treatment state specimen when the deflection is the same. With the finite element model verified by experiments, the variation laws of equivalent stress and effective plastic strain of 6061 aluminum sheets in different states were analyzed, and the influence of work hardening exponent n and strength coefficient K on the springback and cross‐section deformation were also obtained. The springback increases when the work hardening exponent n decreases gradually, and the uneven deformation increases with the increase of strength coefficient K. With the increase of strength coefficient K, the warpage and the thinning rate increases gradually. As the artificial aging time extends, the springback and cross‐section deformation increase.