PSI - Issue 72

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ScienceDirect

Procedia Structural Integrity 72 (2025) 345–353

12th Annual Conference of Society for Structural Integrity and Life (DIVK12) Sensitivity analysis using digital twins for tensile tests Levente Tatár a, *, Dániel Antók a , Tamás Fekete a , Péter Bereczki b a HUN-REN Centre for Energy Research, Institute for Atomic Energy Research, Konkoly-Thege Miklós út 29-33., Budapest 1121, Hungary b University of Dunaújváros, Táncsics Mihály utca, Dunaújváros, 2400, Hungary Abstract Tensile testing is one of the most important (if not the most important) material testing method for determining material properties for metals. As there is an increased need for more precise simulations in industry, there is a huge demand for more precise flow curves for ductile materials. It is well known that the evaluation of tensile tests by simple analytical formulae can only be considered reliable until necking. Besides, in some situations using the usual cylindrical specimens is not possible / impractical. To overcome these difficulties a Digital Twin (DT) based approach has been used. Tensile tests were executed at the University of Dunaújváros on specially prepared flat specimens. Prior to the tests the coordinates of the specimens were measured by a coordinate measuring machine. A regular grid has been painted on the surface of the specimens. During the test the generally used longitudinal type strain gauges were superseded by observation with video cameras. Based on these measurements, simplified (2D and 3D) and more precise 3D FEM models have been made. The precise FEM model can be considered the DT of the specimen. The results confirm the validity of the Considère criterion. There is a clear difference between development of necking for models using idealized and more realistic shape of the specimens. The initially very small differences lead to considerable difference of the post-necking part of the longitudinal strain – force curve thus leading to an ambiguity of the end part of the flow-curve. © 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of Aleksandar Sedmak, Branislav Djordjevic, Simon Sedmak Dr. Simon Sedmak, ssedmak@mas.bg.ac.rs, Innovation Center of Faculty of Mechanical Engineering, Belgrade, Serbia

Keywords: Tensile test; flowcurve; post-necking behavour; FEM; Considère criterion; flat specimen; realistic geometry; digital twin

* Corresponding author. E-mail address: tatar.levente@ek.hun-ren.hu

2452-3216 © 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of Aleksandar Sedmak, Branislav Djordjevic, Simon Sedmak Dr. Simon Sedmak, ssedmak@mas.bg.ac.rs, Innovation Center of Faculty of Mechanical Engineering, Belgrade, Serbia 10.1016/j.prostr.2025.08.113