Researth For Bending Forming Beheavior Of Automotive Aluminum Section-Beam

With the increasing of serious energy problem in today’s society, thedesign of automobile lightweight become more and more concerned.Aluminum frame body contained a variety of closed cross-section shape ofthe profile bending parts which had the advantages of lightweight and highsafety. Aluminum frame body could achieve the reduction in weight of thecar and the purpose of energy saving and was concerned by the automobilemanufacture. Stretch bending was the main forming method of aluminumsection-beam. But the springback and section distortion were the mainfactors of stretch bending. In the bending, the material stress state wascomplex and the springback and section distortion were very difficult topredict because of the influence of material property and friction. In thispaper, in order to reduce the cost of experiments and shorten the test cycle,the bending and stretch bending were investigated through experimentsand numerical simulation.In this paper, three-point bending experiment was introducedsystematically. Bending force was measured by strain gauges and thecauses of errors are analyzed in the calibration of the strain gauges. Therelationship between bending force and feedback voltage was identified.Three-point bending experiment was done in the servo press and thesection distortion was measured by the laser.In order to get mechanical performance parameters, cut samplesfrom the rectangular aluminum section-beam and conducted a tensile test.Considering the effect of boundary condition and indenter, established aFE model for the bend-forming process of rectangular aluminumsection-beam by ABAQUS and analyzed the process of three point bending. Then made a comparison of results between experiments andnumerical simulations, and the FE model was proved reliable. Performedan analysis of influence factors, like section height, section width,thickness, roller radius and bending span, and studied their influence onthe section distortion of rectangular aluminum section-beam. On the basisof least square method, this article deduced a math model for theinfluencing law. The model was verified.Simulated the stretch bending process of rectangular aluminumsection-beam with the validated FE model and analyzed influence factors,such as stretch bending radius, pre-stretch bending and post-stretchbending, and study their effect on section distortion of rectangularaluminum section-beam and the elastic recoil after unload.