Stretch-bending analysis of U-section beams

A complete analysis for stretch-bending of U-section beams is introduced. The variations of the applied bending moment with the applied axial load for fully elastic, elastic-plastic and fully plastic conditions are derived. The ultimate goal of such simulation technique is to develop a simple and fast technique to determine stresses, strains, springback and residual stresses as functions of parameters such as material characteristics, forming Loads and the required geometry of U-section beams. The model proposed in the present study can be considered as a major step for computer simulation of stretch-bending at the design stage which will provide useful data and criteria for equipment selection and tooling design. The significance of various material parameters from productibility, ease of fabrication and tool design viewpoints can also be evaluated by the model. Furthermore, the failure modes of the stretch-bending process are also introduced and the region for safe operations are defined in a very useful and practical set of curves. (C) 1997 Elsevier Science Ltd.