Validation of material models for sheet metals using an innovative tool

• Applicant: Professor Dr.-Ing. Wolfram Volk
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 455388465

As for all models, a validation prior to their use is essential for material models of sheet materials as well. In a groundwork, an innovative tool was developed, which allows a more effective and efficient possibility of material model validation for sheets. The fundamental ability of the new tool to generate data for validation was demonstrated. Thereby the basic ability of the new tool to generate data for validation was shown.The aim of the research project is to develop and implement a validation strategy for material models of sheet materials using the innovative tool concept. The focus is on the yield locus and its hardening behavior. In the first phase, extensive experimental investigations using materials from three different material classes (IF-steel, DP-steel, aluminum) will be carried out. On the one hand, different influences on the test results are investigated, on the other hand, a comprehensive database for the following work packages is generated. In order to decidedly validate the hardening mechanisms, different orientations of the specimen with regard to the rolling direction are investigated on the tool. In addition, pre-stretched specimens are examined on the new tool, which imposes very complex requirements on a material model with regard to the hardening behavior when numerically investigated. In the second phase, various simulation models are built, on the basis of which numerical data for comparison with the experiments is generated. This requires complex material models in order to demonstrate the respective possibilities and limitations of the models used. Furthermore, different parameters of the material models are investigated with regard to their sensitivity to the simulation results. The knowledge gained in this way helps to identify cause-effect relationships and to be able to better assess the simulation results. Finally, the results of the experimental investigations are compared with the numerical results. Based on this, general recommendations for the use of different material models can be derived.The main points of the research project are as follows:1. Conduction and evaluation of non-pre-stretched and pre-stretched validation tests2. Building of simulation models for numerical analyses and fundamental sensitivity analyses on the basis of the tests performed3. Validation of the used material models and deduction of general recommendations

• DFG Programme: Research Grants
• Co-Investigator: Dr.-Ing. Roland Golle