2219铝合金薄壁曲面件拉形过程变形均匀性

In order to improve the deformation uniformity of stretch formed 2219 aluminum alloy thin-walled curved parts, the finite element model based on Hill 1990 anisotropic yield criterion was established and their strain distribution was simulated numerically by using the ABAQUS software. On this basis, the effects of loading path and blank shape on the uniformity of stretching deformation were analysed. Results show that both of the loading path and the blank shape have great influence on the deformation uniformity of the curved parts. If the zigzag paths are used, the 2219 aluminum alloy sheet is compressed at the beginning of loading until it becomes to be a certain arch. In this case, not only the rupture tendency near the left clamp can be alleviated, but also the deformation on the right side of the curved part can increase, so as the deformation uniformity can be improved. Moreover, the deformation uniformity can also be improved by reducing the sheet width where the deformation is insufficient. For example, the sheet with small size in the middle or the trapezoid sheet with larger size in left is recommended. In this case, the stress increases in the narrow area during the stretching process, which makes it undergo greater deformation. In the end, the high performance 2219 aluminum alloy curved parts with good surface quality are obtained by stretch forming of rectangular sheet under a zigzag path.