PSI - Issue 68

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ScienceDirect

Procedia Structural Integrity 68 (2025) 776–781 Structural Integrity Procedia 00 (2024) 000–000 Structural Integrity Procedia 00 (2024) 000–000

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European Conference on Fracture 2024 Refill friction stir spot welding: E ff ects of energy input on residual stresses and mechanical properties in AA6082-T6 Niklaas Becker a,1 , Emad Maawad b , Benjamin Klusemann a,c a Helmholtz-Zentrum Hereon, Institute of Material and Process Design, Solid State Materials Processing, Max-Planck-Straße 1, 21502 Geesthacht, Germany. b Helmholtz-Zentrum Hereon, Institute of Materials Physics, X-ray Di ff raction with Synchrotron Radiation, Notkestrasse 85, D-22607 Hamburg, Germany. c Leuphana University of Lu¨neburg, Institute for Production Technology and Systems, Universita¨tsallee 1, 21335 Lu¨neburg, Germany. Abstract As refill friction stir spot welding is seen as a potential successor to riveting and resistance spot welding in the automotive and aircraft industries, interest in the dynamic load-bearing capacity of welded joints is also growing. Since dynamic load-bearing capacity is strongly dependent on the residual stress state, this study investigated the e ff ects of welding parameters on the residual stress distribution of refill friction stir spot welded joints. In addition to temperature and hardness, residual stresses were measured using X-ray di ff raction. Among other aspects, it is shown that the absolute level of residual stresses within the spot weld does not depend on the welding parameters, but the area in which they act does. © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of ECF24 organizers. Keywords: Refill friction stir spot welding; Residual stress; AA6082-T6 European Conference on Fracture 2024 Refill friction stir spot welding: E ff ects of energy input on residual stresses and mechanical properties in AA6082-T6 Niklaas Becker a,1 , Emad Maawad b , Benjamin Klusemann a,c a Helmholtz-Zentrum Hereon, Institute of Material and Process Design, Solid State Materials Processing, Max-Planck-Straße 1, 21502 Geesthacht, Germany. b Helmholtz-Zentrum Hereon, Institute of Materials Physics, X-ray Di ff raction with Synchrotron Radiation, Notkestrasse 85, D-22607 Hamburg, Germany. c Leuphana University of Lu¨neburg, Institute for Production Technology and Systems, Universita¨tsallee 1, 21335 Lu¨neburg, Germany. Abstract As refill friction stir spot welding is seen as a potential successor to riveting and resistance spot welding in the automotive and aircraft industries, interest in the dynamic load-bearing capacity of welded joints is also growing. Since dynamic load-bearing capacity is strongly dependent on the residual stress state, this study investigated the e ff ects of welding parameters on the residual stress distribution of refill friction stir spot welded joints. In addition to temperature and hardness, residual stresses were measured using X-ray di ff raction. Among other aspects, it is shown that the absolute level of residual stresses within the spot weld does not depend on the welding parameters, but the area in which they act does. © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of ECF24 organizers. Keywords: Refill friction stir spot welding; Residual stress; AA6082-T6 © 2025 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 ECF24 organizers

1. Introduction 1. Introduction

As sustainability continues to be one of the major issues of our and future generations, attention is growing on topics such as lightweight construction and fatigue life in structural engineering. As lightweight construction in large structures can only be implemented with appropriate joining processes, interest in versatile and robust welding meth ods is also inevitably growing. Not all joining processes are suitable for lightweight construction, as some cannot be combined with materials preferred in lightweight construction or the joining technology itself brings a weight penalty. Solid-state joining processes are particularly suitable for lightweight construction, as they do not add any additional As sustainability continues to be one of the major issues of our and future generations, attention is growing on topics such as lightweight construction and fatigue life in structural engineering. As lightweight construction in large structures can only be implemented with appropriate joining processes, interest in versatile and robust welding meth ods is also inevitably growing. Not all joining processes are suitable for lightweight construction, as some cannot be combined with materials preferred in lightweight construction or the joining technology itself brings a weight penalty. Solid-state joining processes are particularly suitable for lightweight construction, as they do not add any additional

∗ Niklaas Becker Tel.: + 49 4152 87-2313. E-mail address: niklaas.becker@hereon.de ∗ Niklaas Becker Tel.: + 49 4152 87-2313. E-mail address: niklaas.becker@hereon.de

2452-3216 © 2025 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 ECF24 organizers 10.1016/j.prostr.2025.06.129 2210-7843 © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of ECF24 organizers. 2210-7843 © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of ECF24 organizers.