STRETCH-BENDING ANALYSIS OF U-SECTION BEAMS

A complete analysis for stretch-bending of U-section beams is introduc ed. The variations of the applied bending moment with the applied axia l load for fully elastic, elastic-plastic and fully plastic conditions are derived. The ultimate goal of such simulation technique is to dev elop a simple and fast technique to determine stresses, strains, sprin gback and residual stresses as functions of parameters such as materia l characteristics, forming Loads and the required geometry of U-sectio n 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 select ion and tooling design. The significance of various material parameter s 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 saf e operations are defined in a very useful and practical set of curves. (C) 1997 Elsevier Science Ltd.