A simulation approach for chaining the forming-welding-crash behaviour of sheet metal structures

In recent years the simulation of manufacturing chains and of the crash behaviour of automotive sheet metal structures has gained more around on its way to be established in accompanying the overall product cycle. In the automotive press and welding plants high accuracy and quality of sheet metal structures is essential in order to achieve the intended passive crashworthiness of the overall vehicle body. So as to describe the manufacturing process chain more precisely and to predict the structural behaviour at early stages of product and production planning, an interlinking of forming, welding and crash models within a structural computation chain is necessary. Considering the structural properties of sheet metal parts after the forming process for simulating welding tasks and finally the crash behaviour requires a multifaceted modelling method. In this paper a practicable strategy of realising the simulation chain forming-welding-crash of sheet metal structures is introduced by means of shell element models. The complete computed results of a forming process simulation, such as residual stresses. plastic strains and material thinning are transferred onto a prepared shell mesh based on the CAD geometry of the component, which satisfies the requirements of a welding computation. Further on, the structural properties after forming, the thermal distribution due to the welding process and the mechanical clamping conditions are combined in a thermo-mechanical computation of the welding effects to calculate the final shape, residual stresses and material thinning of the manufactured sheet metal structure. Finally, the attained structural results are converted into the required data-format by means of a developed conversion routine, which enables the setup of a crash model considering the entire preliminary manufacturing chain. In this contribution the structural behaviour along the introduced simulation chain is analysed step by step and the rendered results are discussed and compared with performed measurements.