Study on Multiple Die Stretch Forming for Curved Surface of Sheet Metal

Multiple die stretch forming (MDSF) is suitable for flexible fabrication, and its several advantages include applicability to various forming processes such as sheet metal forming, single-curved surface forming, and double-curved surface forming. In this study, a systematic numerical simulation of the forming of an atypical double-curved surface by MDSF was performed In the simulation, the urethane pads used to cushion the smooth surface being formed were represented by a hyperelastic material model. The behavior of the elastic recovery deformation was also investigated to evaluate the result of the last forming process, and an experiment was performed to assess the formability of the overall process. The suitability of the MDSF process for forming an atypical double-curved surface was verified by comparing the simulation and experimental results. It was confirmed that MDSF could be used to fabricate the curved surfaces of ships and architectural skin structures of buildings.