2026-04-19T23:01:01Zhttps://ebiltegia.mondragon.edu/oai/request

oai:ebiltegia.mondragon.edu:20.500.11984/10962024-03-06T08:53:26Zcom_20.500.11984_473col_20.500.11984_478

Study on the influence of the springback on the hole expansion ratio characterization Zubia, Biotza Mendiguren, Joseba GALDOS, Lander Sáenz de Argandoña, Eneko Agirre, Julen Formability hole expansion test hole expansion ratio Fortiform 1050 springback Material formability has become one of the main problems, together with the springback, when stamping high added-value components for the automotive industry. The pursuit of weight reduction has led to higher strength alloys which show a lower formability. Among the different formability criteria (e.g. necking, edge strain, fracture and radius cracks) the edge strain is starting to be a critical aspect on the process planning stage. In order to characterise this criteria, the hole expansion ratio (HER) is conducted under the ISO 16630 standard. In the last years, multiple authors have analysed the HER of different alloys and its dependency on different process variables i.e. cutting method, test speed, material strength. However, the influence of the springback phenomenon on the test result has not been previously analysed. In this work, the influence of the springback on the HER values has been analysed for a mild steel DX54D and a third generation steel Fortiform1050 with a novel measuring technique. From the obtained results, it can be stated that the springback has a critical influence on the characterised HER value, mainly for the third generation steel, leading to differences of about 40% on the HER limits. 2018-07-26T14:58:04Z 2018-07-26T14:58:04Z 2018 http://purl.org/coar/resource_type/c_6501 2529-7791 https://katalogoa.mondragon.edu/janium-bin/janium_login_opac.pl?find&ficha_no=147900 https://hdl.handle.net/20.500.11984/1096 eng Attribution-NonCommercial 4.0 International https://creativecommons.org/licenses/by-nc/4.0/ © 2018 B. Zubia et al. Whioce Publishing