Material parameters for sheet metal forming simulations by means of optimisation algorithms

An exact and fast estimation of special material characterisation data and the implementation and usage of these data for finite element simulations are essential for the control of forming processes of special parts from thin sheet metals. This report describes a method to determine the necessary material parameters for the sheet metal forming simulation by means of optimisation algorithms. For the chosen steel grades IF-DCO4, DP500, ZStE340 and AK-DCO4 it is demonstrated how this method works and where its limitations have to be considered. The findings are based on extended material tests, numerous measurements on reference and real parts, and in-depth numerical sensitivity studies on the developed optimisation algorithm. The special simulation programme material parameters delivered from the optimisation process are used to investigate the appropriateness of different material models for the prediction of physically based material parameters. From that, a strategy for the identification of constitutive parameters for sheet metal forming simulations is derived.