Analytical and numerical analysis of a “springback-forming” process dedicated to stiffened panels

The aim of this paper is to present and to analyze the capabilities of a process named “springback-forming”, dedicated to stiffened panels such as airplane׳s fuselage panels. The principle of this forming process is to apply a tension on the stiffener, before the assembly stage with the sheet in a flat configuration using fasteners, adhesives, or a welding process, etc., the bending of the structure is then achieved by springback energy of the stiffener when its tension is released. Using an analytical and finite element models, we studied the capabilities of this process in terms of curvature limits in the case of a single-curved stiffened panel. The results of both models are in good agreement. Through a parametric study, numerical simulations show that when the structure is relatively slender the curvature radius obtained is uniform. Moreover, the value of this radius is independent of the structure׳s length and is mainly limited by the stiffener׳s height. The carried out experimental tests, using laser beam welding as a joining process, demonstrated the feasibility of the process. From the proposed modeling, it is possible to evaluate the range of achievable curvature radius and its uniformity for different values of both geometrical and mechanical parameters of the structure. •We developed a forming process dedicated to stiffened panels.•We obtained a uniform single curved panels using the proposed process.•We developed an analytical and a numerical model of the process.•We analyzed the capabilities and the limitations of the process.•We carried out experimental tests to demonstrate the feasibility of the process.