Experimental study on the incremental forming limit of the aluminum alloy AA2024 sheet

Aluminum alloy AA2024 has superior characteristics, including high specific strength, excellent corrosion resistance, and remarkable mechanical properties. Moreover, it has an undeniable role in the aerospace and automotive industries, which originates from its lightweight. As an advanced sheet metal in the 3D printing technology, the incremental forming process also has unique advantages in the rapid and small batch production of components in aerospace and automotive industries. The present study investigates the mechanical characteristics of AA2024 sheets at different heat treatment conditions. Moreover, effects of different process parameters on the incremental forming limit are studied through tensile and warm incremental forming experiments. It is intended to provide a guideline for aluminum alloy AA2024 sheet forming. Obtained results from tensile strength experiments indicate that the elevated temperature can reduce the tensile strength of AA2024-T4 by 26.14% and increase its uniform elongation by 28.29%. Incremental forming experiments show that as the temperature increases, the forming angle limit of AA2024-T4 increases by 21.98%. However, it is still lower than the forming angle limit of AA2024-O by 18.38% at the room temperature. It is found that a variable-angle busbar shape, larger feed rate, and lower pitch value can make a component with a greater forming limit. Compared with the stamping process, the incremental forming process can significantly increase the forming limit of the AA2024 sheet, indicating that the incremental forming process is a good choice for AA2024 sheet forming.