Investigation on the temperature distribution in the shearing zone during sheet metal blanking to improve the quality of blanking simulation with material separation

• Applicant: Professor Dr.-Ing. Hartmut Hoffmann
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: from 2008 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 56276709

The crack initiation and propagation is of crucial importance for the FE-simulation of shear cutting processes. To model the fracture behavior during the shear cutting process, several fracture criteria were introduced. All fracture criteria are based upon the assumption that the separation of the material is initiated at a material specific and constant damage value. However, examinations have shown that the damage value is not really a matter constant. A variation of shear cutting parameters requires an adjustment of the value. Consequently the blanked sheet metal surface cant be simulated with adequate quality in advance. It is always necessary to adjust the simulation with practical experiments.There is a divergence of opinions regarding the extent of the temperature rise in the shearing zone during sheet metal blanking in literature. Many authors assume that the temperature rise during the blanking process is not significant. In contrast other scientists write about very high temperatures up to 750°C. Assuming such high temperatures and at the same time neglecting the temperature in the process view is incorrect.Due to the importance of the temperature it is attempted to measure the resulting temperature distribution during the blanking process on the cutting edge of the blanking punch in this project. Based on these results, the temperature influence should be embedded in the FE-simulation of shear cutting processes and the corresponding damage criteria to achieve a fracture initiation and propagation close to reality.

• DFG Programme: Research Grants
• Participating Person: Dr.-Ing. Roland Golle