Multi-step incremental air-bending forming simulation for U-shaped workpiece with super length and large opening of sheet metal

The sheet metal multiple-step air-bending forming is a common and effective manufacturing process. It is suitable for forming large workpiece without requiring time-consuming setup operations. Most researches on incremental air-bending forming are mainly based on experiments, and on trial and error basis, the forming processes are described through macroscopic metal deformation. ABAQUS finite element model based on Hill's anisotropic yield criterion under plane strain conditions is proposed in this paper for studying multi-step incremental air-bending forming process. The numerical simulation for workpiece forming of sheet metal is performed by ABAQUS/Explicit and Standard solvers. ABAQUS/Explicit module is used to simulate the sheet metal forming process, and ABAQUS/Standard module is utilised to simulate the springback process. The researches show that the results predicted with simulation are very close to the experimental data. It can be taken as a valuable tool for process design of multi-step incremental air-bending forming of sheet metal.