An Improved Process Optimisation for Springback Compensation using FEM Simulation and Experimental Design
Due to elastic deflections after removal of the stamping tools from the part, the part shape does not correspond to the target geometry defined by the designers or customers. The aim of this paper is to present a method to determine the relations between tool geometry, process conditions and formed part geometry. Then these relations are used to optimise process parameters for elastic deflection compensation. The experimental design and the finite element methods are coupled. This is applied on a part showing substantial springback deflections after tool removal. Firstly, the determination of the key parameters to study is done. Then a central composite experimental design is built and the corresponding numerical simulations are carried out. The results so got are the deformed meshes which are postprocessed in order to measure the virtual part geometry. Quadratic mathematical relations between the part geometry and process parameters are established to determine their influence on the part shape, and the process parameters are optimised in order to compensate for elastic deflections. Finally, a forming operation with optimised conditions is designed and a comparison with the experimental drawn part is carried out.
Yann LEDOUX, Eric PAIREL, Robert ARRIEUX
Springback Compensation, Experimental Design, Finite Element Method.