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

International audienceThe aim of this article is to present and to analyze the capabilities of a process named “springback-forming”, dedicated to stiffened panels such asairplane’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 flatconfiguration using fasteners, adhesives, or a welding process... 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 thecase of a single-curved stiffened panel. The results of both models are in good agreement. Through a parametric study, numerical simulations showthat when the structure is relatively slender the curvature radius obtained is uniform. Moreover, the value of this radius is independent of the structure’slength 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