Student from Gifu University, Japan, visiting the IUL

Between November and December 2024, Mr. Hiroto TANABASHI, student at the Gifu University, Japan, conducted research at the Institute of Forming Technology and Lightweight Components (IUL) on the topic “Identification of Fracture Criteria by In-Plane Torsion Testing and Its Application to Blanking”. The study focused on fracture phenomena occurring during the final stages of plastic forming, with the aim of identifying fracture criteria for fracture models used in FEM, such as the Cockcroft-Latham, Ayada, and GTN models. Under the guidance of Prof. Yannis P. Korkolis, Prof. A. Erman Tekkaya and research assistants, in-plane torsion tests were performed to measure fracture strains. Additionally, an analytical model was developed under the same conditions as the experiments, and the results were compared to determine the fracture criteria values. Although some challenges arose during the use of the analysis software, with the support of the IUL team an accurate model closely resembling the experimental setup was successfully created. Ultimately, a reasonable fracture value was identified for the Cockcroft-Latham model. It is intended to investigate the applicability of these results to the blanking process at Gifu University, Japan. Mr. Hiroto TANABASHI would like to express his sincere thanks to the KARL-KOLLE-Foundation for the financial support of his research stay.