[{"doi":"10.1016/j.jajp.2026.100391","date_updated":"2026-03-16T12:38:13Z","volume":13,"author":[{"id":"76631","full_name":"Ludwig, Jean-Patrick","last_name":"Ludwig","first_name":"Jean-Patrick"},{"first_name":"Emil","full_name":"Tolke, Emil","last_name":"Tolke"},{"first_name":"Malte Christian","last_name":"Schlichter","id":"61977","full_name":"Schlichter, Malte Christian"},{"id":"7850","full_name":"Bobbert, Mathias","last_name":"Bobbert","first_name":"Mathias"},{"last_name":"Meschut","orcid":"0000-0002-2763-1246","id":"32056","full_name":"Meschut, Gerson","first_name":"Gerson"}],"intvolume":"        13","citation":{"apa":"Ludwig, J.-P., Tolke, E., Schlichter, M. C., Bobbert, M., &#38; Meschut, G. (2026). Numerical analysis of the robustness of self-pierce riveting with pre-formed joining partners. <i>Journal of Advanced Joining Processes</i>, <i>13</i>, Article 100391. <a href=\"https://doi.org/10.1016/j.jajp.2026.100391\">https://doi.org/10.1016/j.jajp.2026.100391</a>","bibtex":"@article{Ludwig_Tolke_Schlichter_Bobbert_Meschut_2026, title={Numerical analysis of the robustness of self-pierce riveting with pre-formed joining partners}, volume={13}, DOI={<a href=\"https://doi.org/10.1016/j.jajp.2026.100391\">10.1016/j.jajp.2026.100391</a>}, number={100391}, journal={Journal of Advanced Joining Processes}, publisher={Elsevier BV}, author={Ludwig, Jean-Patrick and Tolke, Emil and Schlichter, Malte Christian and Bobbert, Mathias and Meschut, Gerson}, year={2026} }","short":"J.-P. Ludwig, E. Tolke, M.C. Schlichter, M. Bobbert, G. Meschut, Journal of Advanced Joining Processes 13 (2026).","mla":"Ludwig, Jean-Patrick, et al. “Numerical Analysis of the Robustness of Self-Pierce Riveting with Pre-Formed Joining Partners.” <i>Journal of Advanced Joining Processes</i>, vol. 13, 100391, Elsevier BV, 2026, doi:<a href=\"https://doi.org/10.1016/j.jajp.2026.100391\">10.1016/j.jajp.2026.100391</a>.","ama":"Ludwig J-P, Tolke E, Schlichter MC, Bobbert M, Meschut G. Numerical analysis of the robustness of self-pierce riveting with pre-formed joining partners. <i>Journal of Advanced Joining Processes</i>. 2026;13. doi:<a href=\"https://doi.org/10.1016/j.jajp.2026.100391\">10.1016/j.jajp.2026.100391</a>","ieee":"J.-P. Ludwig, E. Tolke, M. C. Schlichter, M. Bobbert, and G. Meschut, “Numerical analysis of the robustness of self-pierce riveting with pre-formed joining partners,” <i>Journal of Advanced Joining Processes</i>, vol. 13, Art. no. 100391, 2026, doi: <a href=\"https://doi.org/10.1016/j.jajp.2026.100391\">10.1016/j.jajp.2026.100391</a>.","chicago":"Ludwig, Jean-Patrick, Emil Tolke, Malte Christian Schlichter, Mathias Bobbert, and Gerson Meschut. “Numerical Analysis of the Robustness of Self-Pierce Riveting with Pre-Formed Joining Partners.” <i>Journal of Advanced Joining Processes</i> 13 (2026). <a href=\"https://doi.org/10.1016/j.jajp.2026.100391\">https://doi.org/10.1016/j.jajp.2026.100391</a>."},"publication_identifier":{"issn":["2666-3309"]},"publication_status":"published","article_number":"100391","_id":"64985","project":[{"name":"TRR 285 - Project Area A","_id":"131"},{"name":"TRR 285 - Subproject A01","_id":"135"},{"_id":"130","name":"TRR 285:  Methodenentwicklung zur mechanischen Fügbarkeit in wandlungsfähigen Prozessketten"}],"department":[{"_id":"9"}],"user_id":"76631","status":"public","type":"journal_article","title":"Numerical analysis of the robustness of self-pierce riveting with pre-formed joining partners","publisher":"Elsevier BV","date_created":"2026-03-16T12:30:39Z","year":"2026","quality_controlled":"1","keyword":["Self-pierce riveting","FE modelling","Plastic pre-deformation","Meta modelling"],"language":[{"iso":"eng"}],"abstract":[{"lang":"eng","text":"Modern industrial development has necessitated a wide range of joining technologies. Self-pierce riveting has become a prevalent technique for sheet metal assembly, especially in automotive applications. Achieving proper joint geometry and adequate load-bearing capacity depends on appropriate tool selection and precise process control. Material properties and condition also play a significant role in process performance. To accommodate the inevitable variations in component characteristics during production, a robust and stable joining process is essential. The study focuses on investigating the influence of preformed joining partners on the joining process and the joint's load capacity. An EN AW-6014 in T4 condition, as well as an HCT590X, are used as materials for this study. For this purpose, an exemplary process chain consisting of the steps of performing, joining, and shear load testing is studied. Each process step is implemented using an FE model to predict the outcome of subsequent steps. For analysis of the influence of pre-strain, an optimisation software is used to plan and execute variations of the process. These variations are used to create a meta-model that can describe the relationships between pre-forming and characteristic parameters of subsequent process steps. The resulting model is validated by comparing simulation and experimental data. Finally, in a novel approach, the robustness of the presented process chain is analyzed in terms of a tolerable performance level for the joining partners."}],"publication":"Journal of Advanced Joining Processes"},{"type":"conference","abstract":[{"text":"In higher education, assessment/examination procedures should be designed to form a coherent learning process that is aligned with the intended learning objectives and planned learning activities. However, in academic teacher education programmes often use assessment formats that are not well aligned with the demands of teachers' actual professional practice. Performance-based assessments can offer an alternative, for example in the form of role-play-based simulations with trained actors representing typical professional activities in environments of reduced complexity. We have developed such a performance-based assessment format for physics teacher education, analogous to the Objective Structured Teaching Examinations (OSTE) approach used in medical education. The OSTE prototype consists of seven short simulative assessments, reflecting four areas of competence (Instruction, Assessment, Pedagogy and Innovation) that form a 90-minute examination course. In order to investigate prospective physics teachers' perceptions of such an assessment format in terms of its suitability as a summative examination procedure, we piloted the OSTE prototype with N = 34 physics student teachers from three German universities using short questionnaires. The results show that participants perceived the OSTE prototype as authentic and relevant, but they also highlight the need for adequate new learning opportunities to prepare for such simulative examinations to be integrated into teacher education programmes.","lang":"eng"}],"status":"public","_id":"62752","user_id":"4245","department":[{"_id":"33"}],"keyword":["teacher education","physics","assessment","pre-service teachers"],"language":[{"iso":"eng"}],"quality_controlled":"1","year":"2025","place":"Copenhagen","citation":{"short":"C. Vogelsang, L. Grotegut, P. Wotschel, T. Janzen, in: Copenhagen, 2025.","bibtex":"@inproceedings{Vogelsang_Grotegut_Wotschel_Janzen_2025, place={Copenhagen}, title={Prospective Physics Teachers’  Perceptions of an Objective Structured  Teaching Examination (OSTE)}, author={Vogelsang, Christoph and Grotegut, Lea and Wotschel, Philipp and Janzen, Thomas}, year={2025} }","mla":"Vogelsang, Christoph, et al. <i>Prospective Physics Teachers’  Perceptions of an Objective Structured  Teaching Examination (OSTE)</i>. 2025.","apa":"Vogelsang, C., Grotegut, L., Wotschel, P., &#38; Janzen, T. (2025). <i>Prospective Physics Teachers’  Perceptions of an Objective Structured  Teaching Examination (OSTE)</i>. ESERA 2025 Conference, Copenhagen.","ama":"Vogelsang C, Grotegut L, Wotschel P, Janzen T. Prospective Physics Teachers’  Perceptions of an Objective Structured  Teaching Examination (OSTE). In: ; 2025.","ieee":"C. Vogelsang, L. Grotegut, P. Wotschel, and T. Janzen, “Prospective Physics Teachers’  Perceptions of an Objective Structured  Teaching Examination (OSTE),” presented at the ESERA 2025 Conference, Copenhagen, 2025.","chicago":"Vogelsang, Christoph, Lea Grotegut, Philipp Wotschel, and Thomas Janzen. “Prospective Physics Teachers’  Perceptions of an Objective Structured  Teaching Examination (OSTE).” Copenhagen, 2025."},"date_updated":"2025-12-03T08:56:29Z","date_created":"2025-12-03T08:43:26Z","author":[{"orcid":"0000-0002-5804-1855","last_name":"Vogelsang","id":"4245","full_name":"Vogelsang, Christoph","first_name":"Christoph"},{"full_name":"Grotegut, Lea","id":"34280","last_name":"Grotegut","first_name":"Lea"},{"first_name":"Philipp","id":"89529","full_name":"Wotschel, Philipp","last_name":"Wotschel"},{"first_name":"Thomas","orcid":"0009-0003-1941-166X","last_name":"Janzen","full_name":"Janzen, Thomas","id":"89329"}],"title":"Prospective Physics Teachers'  Perceptions of an Objective Structured  Teaching Examination (OSTE)","conference":{"location":"Copenhagen","end_date":"2025-08-30","start_date":"2025-08-25","name":"ESERA 2025 Conference"}},{"main_file_link":[{"url":"https://dl.acm.org/doi/10.1145/3627673.3679923"}],"conference":{"location":"Boise, ID, USA","end_date":"2024-10-25","start_date":"2024-10-21","name":"CIKM '24: Proceedings of the 33rd ACM International Conference on Information and Knowledge Management"},"doi":"10.1145/3627673.3679923","date_updated":"2025-09-11T09:49:07Z","author":[{"first_name":"Umair","last_name":"Qudus","orcid":"0000-0001-6714-8729","id":"83392","full_name":"Qudus, Umair"},{"first_name":"Michael","id":"67199","full_name":"Röder, Michael","orcid":"https://orcid.org/0000-0002-8609-8277","last_name":"Röder"},{"full_name":"Vollmers, Daniel","last_name":"Vollmers","first_name":"Daniel"},{"first_name":"Axel-Cyrille","last_name":"Ngonga Ngomo","id":"65716","full_name":"Ngonga Ngomo, Axel-Cyrille"}],"volume":9,"citation":{"apa":"Qudus, U., Röder, M., Vollmers, D., &#38; Ngonga Ngomo, A.-C. (2024). ExPrompt: Augmenting Prompts Using Examples as Modern Baseline for Stance Classification. <i>Proceedings of the 33rd ACM International Conference on Information and Knowledge Management</i>, <i>9</i>, 3994–3999. <a href=\"https://doi.org/10.1145/3627673.3679923\">https://doi.org/10.1145/3627673.3679923</a>","mla":"Qudus, Umair, et al. “ExPrompt: Augmenting Prompts Using Examples as Modern Baseline for Stance Classification.” <i>Proceedings of the 33rd ACM International Conference on Information and Knowledge Management</i>, vol. 9, ACM, 2024, pp. 3994–99, doi:<a href=\"https://doi.org/10.1145/3627673.3679923\">10.1145/3627673.3679923</a>.","short":"U. Qudus, M. Röder, D. Vollmers, A.-C. Ngonga Ngomo, in: Proceedings of the 33rd ACM International Conference on Information and Knowledge Management, ACM, 2024, pp. 3994–3999.","bibtex":"@inproceedings{Qudus_Röder_Vollmers_Ngonga Ngomo_2024, title={ExPrompt: Augmenting Prompts Using Examples as Modern Baseline for Stance Classification}, volume={9}, DOI={<a href=\"https://doi.org/10.1145/3627673.3679923\">10.1145/3627673.3679923</a>}, booktitle={Proceedings of the 33rd ACM International Conference on Information and Knowledge Management}, publisher={ACM}, author={Qudus, Umair and Röder, Michael and Vollmers, Daniel and Ngonga Ngomo, Axel-Cyrille}, year={2024}, pages={3994–3999} }","chicago":"Qudus, Umair, Michael Röder, Daniel Vollmers, and Axel-Cyrille Ngonga Ngomo. “ExPrompt: Augmenting Prompts Using Examples as Modern Baseline for Stance Classification.” In <i>Proceedings of the 33rd ACM International Conference on Information and Knowledge Management</i>, 9:3994–99. ACM, 2024. <a href=\"https://doi.org/10.1145/3627673.3679923\">https://doi.org/10.1145/3627673.3679923</a>.","ieee":"U. Qudus, M. Röder, D. Vollmers, and A.-C. Ngonga Ngomo, “ExPrompt: Augmenting Prompts Using Examples as Modern Baseline for Stance Classification,” in <i>Proceedings of the 33rd ACM International Conference on Information and Knowledge Management</i>, Boise, ID, USA, 2024, vol. 9, pp. 3994–3999, doi: <a href=\"https://doi.org/10.1145/3627673.3679923\">10.1145/3627673.3679923</a>.","ama":"Qudus U, Röder M, Vollmers D, Ngonga Ngomo A-C. ExPrompt: Augmenting Prompts Using Examples as Modern Baseline for Stance Classification. In: <i>Proceedings of the 33rd ACM International Conference on Information and Knowledge Management</i>. Vol 9. ACM; 2024:3994-3999. doi:<a href=\"https://doi.org/10.1145/3627673.3679923\">10.1145/3627673.3679923</a>"},"page":"3994 - 3999","intvolume":"         9","publication_status":"published","publication_identifier":{"isbn":["79-8-4007-0436-9/24/10"]},"has_accepted_license":"1","file_date_updated":"2024-11-11T13:24:19Z","project":[{"_id":"412","name":"NEBULA: Nutzerzentrierte KI-basierte Erkennung von Fake-News und Fehlinformationen"}],"_id":"56983","user_id":"83392","status":"public","type":"conference","popular_science":"1","title":"ExPrompt: Augmenting Prompts Using Examples as Modern Baseline for Stance Classification","publisher":"ACM","date_created":"2024-11-11T13:15:25Z","year":"2024","quality_controlled":"1","ddc":["006"],"keyword":["Stance Classification","Few-shot in-context learning","Pre-trained large language models"],"language":[{"iso":"eng"}],"abstract":[{"lang":"eng","text":"Detecting the veracity of a statement automatically is a challenge the world is grappling with due to the vast amount of data spread across the web. Verifying a given claim typically entails validating it within the framework of supporting evidence like a retrieved piece of text. Classifying the stance of the text with respect to the claim is called stance classification. Despite advancements in automated fact-checking, most systems still rely on a substantial quantity of labeled training data, which can be costly. In this work, we avoid the costly training or fine-tuning of models by reusing pre-trained large language models together with few-shot in-context learning. Since we do not train any model, our approach ExPrompt is lightweight, demands fewer resources than other stance classification methods and can serve as a modern baseline for future developments. At the same time, our evaluation shows that our approach is able to outperform former state-of-the-art stance classification approaches regarding accuracy by at least 2 percent. Our scripts and data used in this paper are available at https://github.com/dice-group/ExPrompt."}],"file":[{"file_size":531579,"file_id":"56984","access_level":"closed","file_name":"public.pdf","date_updated":"2024-11-11T13:24:19Z","date_created":"2024-11-11T13:24:19Z","creator":"uqudus","success":1,"relation":"main_file","content_type":"application/pdf"}],"publication":"Proceedings of the 33rd ACM International Conference on Information and Knowledge Management"},{"conference":{"name":"15th Conference of the European Science Education Research Association (ESERA)","location":"Cappadocia"},"title":"Evidence based practice of pre-service teachers","date_created":"2025-12-08T09:56:33Z","author":[{"first_name":"Pascal","id":"44191","full_name":"Pollmeier, Pascal","last_name":"Pollmeier"},{"last_name":"Vogelsang","orcid":"0000-0002-5804-1855","full_name":"Vogelsang, Christoph","id":"4245","first_name":"Christoph"},{"id":"54823","full_name":"Fechner, Sabine","last_name":"Fechner","orcid":"0000-0001-5645-5870","first_name":"Sabine"}],"date_updated":"2025-12-13T23:45:09Z","citation":{"apa":"Pollmeier, P., Vogelsang, C., &#38; Fechner, S. (2023). Evidence based practice of pre-service teachers. <i>15th Conference of the European Science Education Research Association (ESERA)</i>. 15th Conference of the European Science Education Research Association (ESERA), Cappadocia.","mla":"Pollmeier, Pascal, et al. “Evidence Based Practice of Pre-Service Teachers.” <i>15th Conference of the European Science Education Research Association (ESERA)</i>, 2023.","bibtex":"@inproceedings{Pollmeier_Vogelsang_Fechner_2023, title={Evidence based practice of pre-service teachers}, booktitle={15th Conference of the European Science Education Research Association (ESERA)}, author={Pollmeier, Pascal and Vogelsang, Christoph and Fechner, Sabine}, year={2023} }","short":"P. Pollmeier, C. Vogelsang, S. Fechner, in: 15th Conference of the European Science Education Research Association (ESERA), 2023.","ieee":"P. Pollmeier, C. Vogelsang, and S. Fechner, “Evidence based practice of pre-service teachers,” presented at the 15th Conference of the European Science Education Research Association (ESERA), Cappadocia, 2023.","chicago":"Pollmeier, Pascal, Christoph Vogelsang, and Sabine Fechner. “Evidence Based Practice of Pre-Service Teachers.” In <i>15th Conference of the European Science Education Research Association (ESERA)</i>, 2023.","ama":"Pollmeier P, Vogelsang C, Fechner S. Evidence based practice of pre-service teachers. In: <i>15th Conference of the European Science Education Research Association (ESERA)</i>. ; 2023."},"year":"2023","quality_controlled":"1","language":[{"iso":"eng"}],"keyword":["Epistemologie","Evidenzen","Daten","Umgang mit Daten","Kompetenzen","Studierende","pre-service teachers"],"user_id":"54823","department":[{"_id":"386"},{"_id":"33"}],"_id":"62969","status":"public","type":"conference_abstract","publication":"15th Conference of the European Science Education Research Association (ESERA)"},{"page":"49-57","citation":{"ieee":"F. Schröer and C. Tenberge, “How to enable pre-service teachers to design technological teaching and learning inclusively? – On the nature and consideration of basic needs in teacher training,” in <i>PATT39 - PATT on the Edge Technology, Innovation and Education</i>, St. John’s, Newfoundland and Labrador, Canada, 2022, pp. 49–57.","chicago":"Schröer, Franz, and Claudia Tenberge. “How to Enable Pre-Service Teachers to Design Technological Teaching and Learning Inclusively? – On the Nature and Consideration of Basic Needs in Teacher Training.” In <i>PATT39 - PATT on the Edge Technology, Innovation and Education</i>, edited by David Gill, Jim Tuff, Thomas Kennedy, Shawn Pendergast, and Sana Jamil, 49–57. PATT Proceedings. St. John’s, Newfoundland and Labrador, Canada, 2022.","ama":"Schröer F, Tenberge C. How to enable pre-service teachers to design technological teaching and learning inclusively? – On the nature and consideration of basic needs in teacher training. In: Gill D, Tuff J, Kennedy T, Pendergast S, Jamil S, eds. <i>PATT39 - PATT on the Edge Technology, Innovation and Education</i>. PATT Proceedings. ; 2022:49-57.","mla":"Schröer, Franz, and Claudia Tenberge. “How to Enable Pre-Service Teachers to Design Technological Teaching and Learning Inclusively? – On the Nature and Consideration of Basic Needs in Teacher Training.” <i>PATT39 - PATT on the Edge Technology, Innovation and Education</i>, edited by David Gill et al., 2022, pp. 49–57.","bibtex":"@inproceedings{Schröer_Tenberge_2022, place={St. John’s, Newfoundland and Labrador, Canada}, series={PATT Proceedings}, title={How to enable pre-service teachers to design technological teaching and learning inclusively? – On the nature and consideration of basic needs in teacher training}, booktitle={PATT39 - PATT on the Edge Technology, Innovation and Education}, author={Schröer, Franz and Tenberge, Claudia}, editor={Gill, David and Tuff, Jim and Kennedy, Thomas and Pendergast, Shawn and Jamil, Sana}, year={2022}, pages={49–57}, collection={PATT Proceedings} }","short":"F. Schröer, C. Tenberge, in: D. Gill, J. Tuff, T. Kennedy, S. Pendergast, S. Jamil (Eds.), PATT39 - PATT on the Edge Technology, Innovation and Education, St. John’s, Newfoundland and Labrador, Canada, 2022, pp. 49–57.","apa":"Schröer, F., &#38; Tenberge, C. (2022). How to enable pre-service teachers to design technological teaching and learning inclusively? – On the nature and consideration of basic needs in teacher training. In D. Gill, J. Tuff, T. Kennedy, S. Pendergast, &#38; S. Jamil (Eds.), <i>PATT39 - PATT on the Edge Technology, Innovation and Education</i> (pp. 49–57)."},"place":"St. John’s, Newfoundland and Labrador, Canada","publication_identifier":{"unknown":["https://research.edgehill.ac.uk/ws/portalfiles/portal/50821651/patt39_proceedings_june_17_2022.pdf"]},"publication_status":"published","conference":{"start_date":"2022-06-21","name":"PATT39 - PATT on the Edge Technology, Innovation and Education","location":"St. John’s, Newfoundland and Labrador, Canada","end_date":"2022-06-24"},"main_file_link":[{"url":"https://research.edgehill.ac.uk/ws/portalfiles/portal/50821651/patt39_proceedings_june_17_2022.pdf"}],"author":[{"first_name":"Franz","id":"71764","full_name":"Schröer, Franz","last_name":"Schröer"},{"id":"67302","full_name":"Tenberge, Claudia","last_name":"Tenberge","first_name":"Claudia"}],"date_updated":"2023-01-25T15:13:57Z","status":"public","editor":[{"full_name":"Gill, David","last_name":"Gill","first_name":"David"},{"first_name":"Jim","last_name":"Tuff","full_name":"Tuff, Jim"},{"first_name":"Thomas","last_name":"Kennedy","full_name":"Kennedy, Thomas"},{"last_name":"Pendergast","full_name":"Pendergast, Shawn","first_name":"Shawn"},{"first_name":"Sana","full_name":"Jamil, Sana","last_name":"Jamil"}],"type":"conference","department":[{"_id":"588"}],"user_id":"71764","series_title":"PATT Proceedings","_id":"40046","year":"2022","quality_controlled":"1","title":"How to enable pre-service teachers to design technological teaching and learning inclusively? – On the nature and consideration of basic needs in teacher training","date_created":"2023-01-25T15:13:45Z","abstract":[{"lang":"eng","text":"Theoretical approaches to the transformation towards an inclusive educational system in Germany mostly agree on the involvement of developmental tasks in subject related research (Hinz, 2011). The common understanding of inclusion as a process geared towards equal participation of all children (Booth, 2012) requires a reflexive questioning of established values, attitudes and practices in order to develop inclusive subject related research, teacher training and teaching and learning (Pech & Schomaker, 2013). Among other things, this results in consequences for the design of pre- service teacher training. To a large extent, teacher education is driven by the promotion of central competencies, interests and self-efficacy (Baumert & Kunter, 2011). It aims towards the development and realisation of inclusive interdisciplinary science and social studies (‘Sachunterricht’) in primary education (Moser, 2018). In conjunction with largely acknowledged constructivist approaches to teaching and learning (Möller, 2001), the development of personality, the consideration of basic needs (Deci & Ryan, 1993) and promotion of individual potentials are repeatedly fundamentally represented in subject related and pedagogical considerations (Feuser, 1989; GDSU, 2013). Therefore, the aforementioned constructivist approach is connected to several certain key paradigms for teaching and learning processes (e.g., Vygotskij, 1978; Posner et al., 1982; van de Pol et al., 2010). In this regard, the nature of primary school students’ basic needs have empirically not been sufficiently studied yet. Theoretical frameworks from motivational psychology (Deci & Ryan, 1993) do not explicitly address how individual needs differ and how the diversity of needs can be included in joint-learning, multi-perspective technology education classes. The research project the present paper is part of aims to develop a research-based concept for the professionalisation of pre-service teachers in a seminar course. Therefore, the promotion of the pre- service teachers’ interests and self-efficacy expectations have been assessed in a pre-post research design with a control group visiting another course not related to technology education and inclusion. The present paper describes and discusses first results of the project and will give an outlook on subsequent developmental tasks."}],"publication":"PATT39 - PATT on the Edge Technology, Innovation and Education","language":[{"iso":"eng"}],"keyword":["Inclusion","basic needs","pre-service teacher training","interest","self-efficacy"]},{"quality_controlled":"1","publication_status":"published","year":"2021","place":"Cham","page":"1495-1506","citation":{"ama":"Uhe B, Kuball C-M, Merklein M, Meschut G. Self-Piercing Riveting Using Rivets Made of Stainless Steel with High Strain Hardening. In: Daehn G, Cao J, Kinsey B, Tekkaya E, Vivek A, Yoshida Y, eds. <i>Forming the Future - Proceedings of the 13th International Conference on the Technology of Plasticity. The Minerals, Metals &#38; Materials Series.</i> Springer; 2021:1495-1506. doi:<a href=\"https://doi.org/10.1007/978-3-030-75381-8_124\">10.1007/978-3-030-75381-8_124</a>","chicago":"Uhe, Benedikt, Clara-Maria Kuball, Marion Merklein, and Gerson Meschut. “Self-Piercing Riveting Using Rivets Made of Stainless Steel with High Strain Hardening.” In <i>Forming the Future - Proceedings of the 13th International Conference on the Technology of Plasticity. The Minerals, Metals &#38; Materials Series.</i>, edited by Glenn Daehn, Jian Cao, Brad Kinsey, Erman Tekkaya, Anupam Vivek, and Yoshinori Yoshida, 1495–1506. Cham: Springer, 2021. <a href=\"https://doi.org/10.1007/978-3-030-75381-8_124\">https://doi.org/10.1007/978-3-030-75381-8_124</a>.","ieee":"B. Uhe, C.-M. Kuball, M. Merklein, and G. Meschut, “Self-Piercing Riveting Using Rivets Made of Stainless Steel with High Strain Hardening,” in <i>Forming the Future - Proceedings of the 13th International Conference on the Technology of Plasticity. The Minerals, Metals &#38; Materials Series.</i>, G. Daehn, J. Cao, B. Kinsey, E. Tekkaya, A. Vivek, and Y. Yoshida, Eds. Cham: Springer, 2021, pp. 1495–1506.","short":"B. Uhe, C.-M. Kuball, M. Merklein, G. Meschut, in: G. Daehn, J. Cao, B. Kinsey, E. Tekkaya, A. Vivek, Y. Yoshida (Eds.), Forming the Future - Proceedings of the 13th International Conference on the Technology of Plasticity. The Minerals, Metals &#38; Materials Series., Springer, Cham, 2021, pp. 1495–1506.","bibtex":"@inbook{Uhe_Kuball_Merklein_Meschut_2021, place={Cham}, title={Self-Piercing Riveting Using Rivets Made of Stainless Steel with High Strain Hardening}, DOI={<a href=\"https://doi.org/10.1007/978-3-030-75381-8_124\">10.1007/978-3-030-75381-8_124</a>}, booktitle={Forming the Future - Proceedings of the 13th International Conference on the Technology of Plasticity. The Minerals, Metals &#38; Materials Series.}, publisher={Springer}, author={Uhe, Benedikt and Kuball, Clara-Maria and Merklein, Marion and Meschut, Gerson}, editor={Daehn, Glenn and Cao, Jian and Kinsey, Brad and Tekkaya, Erman and Vivek, Anupam and Yoshida, Yoshinori}, year={2021}, pages={1495–1506} }","mla":"Uhe, Benedikt, et al. “Self-Piercing Riveting Using Rivets Made of Stainless Steel with High Strain Hardening.” <i>Forming the Future - Proceedings of the 13th International Conference on the Technology of Plasticity. The Minerals, Metals &#38; Materials Series.</i>, edited by Glenn Daehn et al., Springer, 2021, pp. 1495–506, doi:<a href=\"https://doi.org/10.1007/978-3-030-75381-8_124\">10.1007/978-3-030-75381-8_124</a>.","apa":"Uhe, B., Kuball, C.-M., Merklein, M., &#38; Meschut, G. (2021). Self-Piercing Riveting Using Rivets Made of Stainless Steel with High Strain Hardening. In G. Daehn, J. Cao, B. Kinsey, E. Tekkaya, A. Vivek, &#38; Y. Yoshida (Eds.), <i>Forming the Future - Proceedings of the 13th International Conference on the Technology of Plasticity. The Minerals, Metals &#38; Materials Series.</i> (pp. 1495–1506). Springer. <a href=\"https://doi.org/10.1007/978-3-030-75381-8_124\">https://doi.org/10.1007/978-3-030-75381-8_124</a>"},"publisher":"Springer","date_updated":"2026-02-27T10:40:39Z","date_created":"2021-08-04T14:02:32Z","author":[{"last_name":"Uhe","full_name":"Uhe, Benedikt","id":"38131","first_name":"Benedikt"},{"full_name":"Kuball, Clara-Maria","last_name":"Kuball","first_name":"Clara-Maria"},{"first_name":"Marion","full_name":"Merklein, Marion","last_name":"Merklein"},{"full_name":"Meschut, Gerson","id":"32056","orcid":"0000-0002-2763-1246","last_name":"Meschut","first_name":"Gerson"}],"title":"Self-Piercing Riveting Using Rivets Made of Stainless Steel with High Strain Hardening","doi":"10.1007/978-3-030-75381-8_124","publication":"Forming the Future - Proceedings of the 13th International Conference on the Technology of Plasticity. The Minerals, Metals & Materials Series.","type":"book_chapter","editor":[{"first_name":"Glenn","last_name":"Daehn","full_name":"Daehn, Glenn"},{"full_name":"Cao, Jian","last_name":"Cao","first_name":"Jian"},{"first_name":"Brad","last_name":"Kinsey","full_name":"Kinsey, Brad"},{"first_name":"Erman","full_name":"Tekkaya, Erman","last_name":"Tekkaya"},{"first_name":"Anupam","full_name":"Vivek, Anupam","last_name":"Vivek"},{"last_name":"Yoshida","full_name":"Yoshida, Yoshinori","first_name":"Yoshinori"}],"abstract":[{"text":"Self-piercing riveting is an established technique for joining multi-material structures in car body manufacturing. Rivets for self-piercing riveting differ in their geometry, the material used, the condition of the material and their surface condition. To shorten the manufacturing process by omitting the heat treatment and the coating process, the authors have elaborated a concept for the use of stainless steel with high strain hardening as a rivet material. The focus of the present investigation is on the evaluation of the influences of the rivet’s geometry and material on its deformation behaviour. Conventional rivets of types P and HD2, a rivet with an improved geometry made of treatable steel 38B2, and rivets made of the stainless steels 1.3815 and 1.4541 are examined. The analysis is conducted by means of multi-step joining tests for two material combinations comprising high-strength steel HCT70X and aluminium EN AW-5083. The joints are cut to provide a cross-section and the deformation behaviour of the different rivets is analysed on the basis of the measured changes in geometry and hardness. In parallel, an examination of the force-stroke curves provides further insights. It can be demonstrated that, besides the geometry, the material strength, in particular, has a significant influence on the deformation behaviour of the rivet. The strength of steel 1.4541 is seen to be too low for the joining task, while the strength of steel 1.3815 is sufficient, and hence the investigation confirms the capability of rivets made of 1.3815 for joining even challenging material combinations.","lang":"eng"}],"status":"public","_id":"22930","department":[{"_id":"157"}],"user_id":"53912","keyword":["Self-piercing riveting","Lightweight design","Deformation behaviour","Stainless steel","High nitrogen steel"],"language":[{"iso":"eng"}]},{"type":"journal_article","publication":"Journal of Advanced Joining Processes. ","status":"public","user_id":"34782","department":[{"_id":"157"}],"project":[{"grant_number":"418701707","_id":"130","name":"TRR 285: TRR 285"},{"_id":"131","name":"TRR 285 - A: TRR 285 - Project Area A"},{"_id":"135","name":"TRR 285 – A01: TRR 285 - Subproject A01"}],"_id":"20678","language":[{"iso":"eng"}],"keyword":["Clinching","process simulation","FEM","pre-straining","sensitivity analysis"],"publication_status":"published","publication_identifier":{"unknown":["https://doi.org/10.1016/j.jajp.2020.100038"]},"citation":{"apa":"Bielak, C. R., Böhnke, M., Beck, R., Bobbert, M., &#38; Meschut, G. (2020). Numerical analysis of the robustness of clinching process considering the pre-forming of the parts . <i>Journal of Advanced Joining Processes. </i>. <a href=\"https://doi.org/10.1016/j.jajp.2020.100038\">https://doi.org/10.1016/j.jajp.2020.100038</a>","short":"C.R. Bielak, M. Böhnke, R. Beck, M. Bobbert, G. Meschut, Journal of Advanced Joining Processes.  (2020).","bibtex":"@article{Bielak_Böhnke_Beck_Bobbert_Meschut_2020, title={Numerical analysis of the robustness of clinching process considering the pre-forming of the parts }, DOI={<a href=\"https://doi.org/10.1016/j.jajp.2020.100038\">https://doi.org/10.1016/j.jajp.2020.100038</a>}, journal={Journal of Advanced Joining Processes. }, publisher={Elsevier}, author={Bielak, Christian Roman and Böhnke, Max and Beck, Robert and Bobbert, Mathias and Meschut, Gerson}, year={2020} }","mla":"Bielak, Christian Roman, et al. “Numerical Analysis of the Robustness of Clinching Process Considering the Pre-Forming of the Parts .” <i>Journal of Advanced Joining Processes. </i>, Elsevier, 2020, doi:<a href=\"https://doi.org/10.1016/j.jajp.2020.100038\">https://doi.org/10.1016/j.jajp.2020.100038</a>.","ama":"Bielak CR, Böhnke M, Beck R, Bobbert M, Meschut G. Numerical analysis of the robustness of clinching process considering the pre-forming of the parts . <i>Journal of Advanced Joining Processes </i>. Published online 2020. doi:<a href=\"https://doi.org/10.1016/j.jajp.2020.100038\">https://doi.org/10.1016/j.jajp.2020.100038</a>","chicago":"Bielak, Christian Roman, Max Böhnke, Robert Beck, Mathias Bobbert, and Gerson Meschut. “Numerical Analysis of the Robustness of Clinching Process Considering the Pre-Forming of the Parts .” <i>Journal of Advanced Joining Processes. </i>, 2020. <a href=\"https://doi.org/10.1016/j.jajp.2020.100038\">https://doi.org/10.1016/j.jajp.2020.100038</a>.","ieee":"C. R. Bielak, M. Böhnke, R. Beck, M. Bobbert, and G. Meschut, “Numerical analysis of the robustness of clinching process considering the pre-forming of the parts ,” <i>Journal of Advanced Joining Processes. </i>, 2020, doi: <a href=\"https://doi.org/10.1016/j.jajp.2020.100038\">https://doi.org/10.1016/j.jajp.2020.100038</a>."},"year":"2020","date_created":"2020-12-02T16:21:34Z","author":[{"first_name":"Christian Roman","id":"34782","full_name":"Bielak, Christian Roman","last_name":"Bielak"},{"first_name":"Max","last_name":"Böhnke","full_name":"Böhnke, Max","id":"45779"},{"last_name":"Beck","full_name":"Beck, Robert","id":"38279","first_name":"Robert"},{"full_name":"Bobbert, Mathias","id":"7850","last_name":"Bobbert","first_name":"Mathias"},{"full_name":"Meschut, Gerson","id":"32056","orcid":"0000-0002-2763-1246","last_name":"Meschut","first_name":"Gerson"}],"publisher":"Elsevier","date_updated":"2022-03-24T09:39:11Z","doi":"https://doi.org/10.1016/j.jajp.2020.100038","title":"Numerical analysis of the robustness of clinching process considering the pre-forming of the parts "},{"status":"public","type":"journal_article","publication":"European Journal of Operational Research","language":[{"iso":"eng"}],"keyword":["OR in maritime industry","Container pre-marshalling","Terminal operations"],"user_id":"40778","project":[{"name":"Computing Resources Provided by the Paderborn Center for Parallel Computing","_id":"52"}],"_id":"13155","citation":{"apa":"Tanaka, S., &#38; Tierney, K. (2018). Solving Real-World Sized Container Pre-Marshalling Problems with an Iterative Deepening Branch-and-Bound Algorithm. <i>European Journal of Operational Research</i>, <i>264</i>(1), 165–180. <a href=\"https://doi.org/10.1016/j.ejor.2017.05.046\">https://doi.org/10.1016/j.ejor.2017.05.046</a>","short":"S. Tanaka, K. Tierney, European Journal of Operational Research 264 (2018) 165–180.","mla":"Tanaka, Shunji, and Kevin Tierney. “Solving Real-World Sized Container Pre-Marshalling Problems with an Iterative Deepening Branch-and-Bound Algorithm.” <i>European Journal of Operational Research</i>, vol. 264, no. 1, 2018, pp. 165–80, doi:<a href=\"https://doi.org/10.1016/j.ejor.2017.05.046\">https://doi.org/10.1016/j.ejor.2017.05.046</a>.","bibtex":"@article{Tanaka_Tierney_2018, title={Solving Real-World Sized Container Pre-Marshalling Problems with an Iterative Deepening Branch-and-Bound Algorithm}, volume={264}, DOI={<a href=\"https://doi.org/10.1016/j.ejor.2017.05.046\">https://doi.org/10.1016/j.ejor.2017.05.046</a>}, number={1}, journal={European Journal of Operational Research}, author={Tanaka, Shunji and Tierney, Kevin}, year={2018}, pages={165–180} }","ama":"Tanaka S, Tierney K. Solving Real-World Sized Container Pre-Marshalling Problems with an Iterative Deepening Branch-and-Bound Algorithm. <i>European Journal of Operational Research</i>. 2018;264(1):165-180. doi:<a href=\"https://doi.org/10.1016/j.ejor.2017.05.046\">https://doi.org/10.1016/j.ejor.2017.05.046</a>","chicago":"Tanaka, Shunji, and Kevin Tierney. “Solving Real-World Sized Container Pre-Marshalling Problems with an Iterative Deepening Branch-and-Bound Algorithm.” <i>European Journal of Operational Research</i> 264, no. 1 (2018): 165–80. <a href=\"https://doi.org/10.1016/j.ejor.2017.05.046\">https://doi.org/10.1016/j.ejor.2017.05.046</a>.","ieee":"S. Tanaka and K. Tierney, “Solving Real-World Sized Container Pre-Marshalling Problems with an Iterative Deepening Branch-and-Bound Algorithm,” <i>European Journal of Operational Research</i>, vol. 264, no. 1, pp. 165–180, 2018."},"page":"165 - 180","intvolume":"       264","year":"2018","issue":"1","publication_identifier":{"issn":["0377-2217"]},"doi":"https://doi.org/10.1016/j.ejor.2017.05.046","title":"Solving Real-World Sized Container Pre-Marshalling Problems with an Iterative Deepening Branch-and-Bound Algorithm","date_created":"2019-09-09T09:20:25Z","author":[{"last_name":"Tanaka","full_name":"Tanaka, Shunji","first_name":"Shunji"},{"full_name":"Tierney, Kevin","last_name":"Tierney","first_name":"Kevin"}],"volume":264,"date_updated":"2022-01-06T06:51:29Z"},{"type":"journal_article","publication":"Wear","abstract":[{"lang":"eng","text":"The state of the art industrial manufacturing process to produce shafts as counter surfaces for radial shaft seal rings is plunge grinding. This process consists of three major steps. The blank is turned to a slight diameter-oversize followed by the heat treatment and the hard-finishing by plunge grinding. The geometric surface structures of the resulting shafts in general exhibit a stochastic distribution. These surface characteristics contribute to a reliable and stable sealing functionality. And the surface and subsurface hardness generally leads to a higher wear resistance of the shaft. Motivated by economic benefits and in order to achieve a compact production process for at least ten years, turning is investigated as an alternative manufacturing process. However due to the resulting lead structure on the shaft surface and the associated risk of leakage it has not become prevalent yet. In this paper turned shafts of the metastable austenitic steel AISI 347 (1.4550, X6CrNiNb1810) are investigated as alternative material for counter surfaces of radial shaft seal rings and compared to turned shafts of carburized AISI 5115 (1.7131, 16MnCr5). In addition to surfaces dry turned at room-temperature, cryogenic turned AISI 347 counter surfaces are analyzed. By applying cryogenic cooling, the formation of deformation-induced α′-martensite in the surface layer is possible during the turning process. Endurance tests in radial shaft seal ring test rigs are performed and complemented with detailed investigations of microstructure, micro-hardness and surface topography. The results are compared to results of state of the art ground AISI 5115 shafts."}],"status":"public","_id":"34441","user_id":"38077","department":[{"_id":"146"}],"keyword":["Radial shaft seal ring","Shaft surface","Cryogenic turning","Metastable austenitic steel","Deformation-induced martensite formation"],"language":[{"iso":"eng"}],"extern":"1","publication_identifier":{"issn":["0043-1648"]},"year":"2015","citation":{"short":"D. Frölich, B. Magyar, B. Sauer, P. Mayer, B. Kirsch, J.C. Aurich, R. Skorupski, M. Smaga, T. Beck, D. Eifler, Wear 328–329 (2015) 123–131.","mla":"Frölich, D., et al. “Investigation of Wear Resistance of Dry and Cryogenic Turned Metastable Austenitic Steel Shafts and Dry Turned and Ground Carburized Steel Shafts in the Radial Shaft Seal Ring System.” <i>Wear</i>, vol. 328–329, 2015, pp. 123–31, doi:<a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>.","bibtex":"@article{Frölich_Magyar_Sauer_Mayer_Kirsch_Aurich_Skorupski_Smaga_Beck_Eifler_2015, title={Investigation of wear resistance of dry and cryogenic turned metastable austenitic steel shafts and dry turned and ground carburized steel shafts in the radial shaft seal ring system}, volume={328–329}, DOI={<a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>}, journal={Wear}, author={Frölich, D. and Magyar, Balázs and Sauer, B. and Mayer, P. and Kirsch, B. and Aurich, J.C. and Skorupski, R. and Smaga, M. and Beck, T. and Eifler, D.}, year={2015}, pages={123–131} }","apa":"Frölich, D., Magyar, B., Sauer, B., Mayer, P., Kirsch, B., Aurich, J. C., Skorupski, R., Smaga, M., Beck, T., &#38; Eifler, D. (2015). Investigation of wear resistance of dry and cryogenic turned metastable austenitic steel shafts and dry turned and ground carburized steel shafts in the radial shaft seal ring system. <i>Wear</i>, <i>328–329</i>, 123–131. <a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>","ama":"Frölich D, Magyar B, Sauer B, et al. Investigation of wear resistance of dry and cryogenic turned metastable austenitic steel shafts and dry turned and ground carburized steel shafts in the radial shaft seal ring system. <i>Wear</i>. 2015;328-329:123-131. doi:<a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>","chicago":"Frölich, D., Balázs Magyar, B. Sauer, P. Mayer, B. Kirsch, J.C. Aurich, R. Skorupski, M. Smaga, T. Beck, and D. Eifler. “Investigation of Wear Resistance of Dry and Cryogenic Turned Metastable Austenitic Steel Shafts and Dry Turned and Ground Carburized Steel Shafts in the Radial Shaft Seal Ring System.” <i>Wear</i> 328–329 (2015): 123–31. <a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>.","ieee":"D. Frölich <i>et al.</i>, “Investigation of wear resistance of dry and cryogenic turned metastable austenitic steel shafts and dry turned and ground carburized steel shafts in the radial shaft seal ring system,” <i>Wear</i>, vol. 328–329, pp. 123–131, 2015, doi: <a href=\"https://doi.org/10.1016/j.wear.2015.02.004\">https://doi.org/10.1016/j.wear.2015.02.004</a>."},"page":"123-131","date_updated":"2022-12-15T10:18:54Z","date_created":"2022-12-15T10:17:23Z","author":[{"last_name":"Frölich","full_name":"Frölich, D.","first_name":"D."},{"last_name":"Magyar","full_name":"Magyar, Balázs","id":"97759","first_name":"Balázs"},{"full_name":"Sauer, B.","last_name":"Sauer","first_name":"B."},{"first_name":"P.","last_name":"Mayer","full_name":"Mayer, P."},{"full_name":"Kirsch, B.","last_name":"Kirsch","first_name":"B."},{"first_name":"J.C.","last_name":"Aurich","full_name":"Aurich, J.C."},{"full_name":"Skorupski, R.","last_name":"Skorupski","first_name":"R."},{"first_name":"M.","last_name":"Smaga","full_name":"Smaga, M."},{"last_name":"Beck","full_name":"Beck, T.","first_name":"T."},{"first_name":"D.","full_name":"Eifler, D.","last_name":"Eifler"}],"volume":"328-329","title":"Investigation of wear resistance of dry and cryogenic turned metastable austenitic steel shafts and dry turned and ground carburized steel shafts in the radial shaft seal ring system","doi":"https://doi.org/10.1016/j.wear.2015.02.004"},{"abstract":[{"text":"In order to increase mechanical strength, heat dissipation and ampacity and to decrease failure through fatigue fracture, wedge copper wire bonding is being introduced as a standard interconnection method for mass production. To achieve the same process stability when using copper wire instead of aluminum wire a profound understanding of the bonding process is needed. Due to the higher hardness of copper compared to aluminum wire it is more difficult to approach the surfaces of wire and substrate to a level where van der Waals forces are able to arise between atoms. Also, enough friction energy referred to the total contact area has to be generated to activate the surfaces. Therefore, a friction model is used to simulate the joining process. This model calculates the resulting energy of partial areas in the contact surface and provides information about the adhesion process of each area. The focus here is on the arising of micro joints in the contact area depending on the location in the contact and time. To validate the model, different touchdown forces are used to vary the initial contact areas of wire and substrate. Additionally, a piezoelectric tri-axial force sensor is built up to identify the known phases of pre-deforming, cleaning, adhering and diffusing for the real bonding process to map with the model. Test substrates as DBC and copper plate are used to show the different formations of a wedge bond connection due to hardness and reaction propensity. The experiments were done by using 500 $\\mu$m copper wire and a standard V-groove tool.","lang":"eng"}],"status":"public","type":"conference","publication":"Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th","keyword":["adhesion","circuit reliability","deformation","diffusion","fatigue cracks","friction","interconnections","lead bonding","van der Waals forces","Cu","adhering process","adhesion process","ampacity improvement","bond quality improvement","cleaning process","diffusing process","fatigue fracture failure","friction energy","friction model","heat dissipation","mechanical strength","piezoelectric triaxial force sensor","predeforming process","size 500 mum","total contact area","van der Waals forces","wedge copper wire bonding","Bonding","Copper","Finite element analysis","Force","Friction","Substrates","Wires"],"language":[{"iso":"eng"}],"_id":"9868","user_id":"55222","department":[{"_id":"151"}],"year":"2014","citation":{"ama":"Althoff S, Neuhaus J, Hemsel T, Sextro W. Improving the bond quality of copper wire bonds using a friction model approach. In: <i>Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th</i>. ; 2014:1549-1555. doi:<a href=\"https://doi.org/10.1109/ECTC.2014.6897500\">10.1109/ECTC.2014.6897500</a>","ieee":"S. Althoff, J. Neuhaus, T. Hemsel, and W. Sextro, “Improving the bond quality of copper wire bonds using a friction model approach,” in <i>Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th</i>, 2014, pp. 1549–1555.","chicago":"Althoff, Simon, Jan Neuhaus, Tobias Hemsel, and Walter Sextro. “Improving the Bond Quality of Copper Wire Bonds Using a Friction Model Approach.” In <i>Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th</i>, 1549–55, 2014. <a href=\"https://doi.org/10.1109/ECTC.2014.6897500\">https://doi.org/10.1109/ECTC.2014.6897500</a>.","apa":"Althoff, S., Neuhaus, J., Hemsel, T., &#38; Sextro, W. (2014). Improving the bond quality of copper wire bonds using a friction model approach. In <i>Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th</i> (pp. 1549–1555). <a href=\"https://doi.org/10.1109/ECTC.2014.6897500\">https://doi.org/10.1109/ECTC.2014.6897500</a>","bibtex":"@inproceedings{Althoff_Neuhaus_Hemsel_Sextro_2014, title={Improving the bond quality of copper wire bonds using a friction model approach}, DOI={<a href=\"https://doi.org/10.1109/ECTC.2014.6897500\">10.1109/ECTC.2014.6897500</a>}, booktitle={Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th}, author={Althoff, Simon and Neuhaus, Jan and Hemsel, Tobias and Sextro, Walter}, year={2014}, pages={1549–1555} }","mla":"Althoff, Simon, et al. “Improving the Bond Quality of Copper Wire Bonds Using a Friction Model Approach.” <i>Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th</i>, 2014, pp. 1549–55, doi:<a href=\"https://doi.org/10.1109/ECTC.2014.6897500\">10.1109/ECTC.2014.6897500</a>.","short":"S. Althoff, J. Neuhaus, T. Hemsel, W. Sextro, in: Electronic Components and Technology Conference (ECTC), 2014 IEEE 64th, 2014, pp. 1549–1555."},"page":"1549-1555","quality_controlled":"1","title":"Improving the bond quality of copper wire bonds using a friction model approach","doi":"10.1109/ECTC.2014.6897500","date_updated":"2019-09-16T10:57:58Z","author":[{"first_name":"Simon","last_name":"Althoff","full_name":"Althoff, Simon"},{"last_name":"Neuhaus","full_name":"Neuhaus, Jan","first_name":"Jan"},{"first_name":"Tobias","last_name":"Hemsel","full_name":"Hemsel, Tobias","id":"210"},{"first_name":"Walter","id":"21220","full_name":"Sextro, Walter","last_name":"Sextro"}],"date_created":"2019-05-20T12:11:44Z"},{"type":"conference","publication":"Proceedings of the 47th International Symposium on Microelectronics (IMAPS)","status":"public","abstract":[{"lang":"eng","text":"Power semiconductor modules are used to control and switch high electrical currents and voltages. Within the power module package wire bonding is used as an interconnection technology. In recent years, aluminum wire has been used preferably, but an ever-growing market of powerful and efficient power modules requires a material with better mechanical and electrical properties. For this reason, a technology change from aluminum to copper is indispensable. However, the copper wire bonding process reacts more sensitive to parameter changes. This makes manufacturing reliable copper bond connections a challenging task. The aim of the BMBF funded project Itsowl-InCuB is the development of self-optimizing techniques to enable the reliable production of copper bond connections under varying conditions. A model of the process is essential to achieve this aim. This model needs to include the dynamic elasto-plastic deformation, the ultrasonic softening effect and the proceeding adhesion between wire and substrate. This paper focusses on the pre-deformation process. In the touchdown phase, the wire is pressed into the V-groove of the tool and a small initial contact area between wire and substrate arise. The local characteristics of the material change abruptly because of the cold forming. Consequently, the pre-deformation has a strong effect on the joining process. In [1], a pre-cleaning effect during the touchdown process of aluminum wires by cracking of oxide layers was presented. These interactions of the process parameters are still largely unknown for copper. In a first step, this paper validates the importance of modeling the pre-deformation by showing its impact on the wire deformation characteristic experimentally. Creating cross-section views of pre-deformed copper wires has shown a low deformation degree compared to aluminum. By using a digital microscope and a scanning confocal microscope an analysis about the contact areas and penetration depths after touchdown has been made. Additionally, it has to be taken into account that the dynamical touchdown force depends on the touchdown speed and the touchdown force set in the bonding machine. In order to measure the overshoot in the force signals, a strain gauge sensor has been used. Subsequently, the affecting factors have been interpreted independently Furthermore, the material properties of copper wire have been investigated with tensile tests and hardness measurements. In a second step, the paper presents finite element models of the touchdown process for source and destination bonds. These models take the measured overshoot in the touchdown forces into account. A multi-linear, isotropic material model has been selected to map the material properties of the copper. A validation of the model with the experimental determined contact areas, normal pressures and penetration depths reveals the high model quality. Thus, the simulation is able to calculate and visualize the three dimensional pre-deformation with an integrated material parameter of the wire if the touchdown parameters of the bonding machine are known. Based on the calculated deformation degrees of wire and substrate, it is probably possible to investigate the effect of the pre-deformation on the pre-cleaning phase in the copper wire bonding."}],"user_id":"210","department":[{"_id":"151"}],"project":[{"grant_number":"02 PQ2210","_id":"92","name":"Intelligente Herstellung zuverlässiger Kupferbondverbindungen"}],"_id":"9895","language":[{"iso":"eng"}],"keyword":["pre-deformation","copper wire bonding","finite element model"],"citation":{"ama":"Unger A, Sextro W, Althoff S, et al. Experimental and Numerical Simulation Study of Pre-Deformed Heavy Copper Wire Wedge Bonds. In: <i>Proceedings of the 47th International Symposium on Microelectronics (IMAPS)</i>. San Diego, CA, US; 2014:289-294.","ieee":"A. Unger <i>et al.</i>, “Experimental and Numerical Simulation Study of Pre-Deformed Heavy Copper Wire Wedge Bonds,” in <i>Proceedings of the 47th International Symposium on Microelectronics (IMAPS)</i>, 2014, pp. 289–294.","chicago":"Unger, Andreas, Walter Sextro, Simon Althoff, Paul Eichwald, Tobias Meyer, Florian Eacock, and Michael Brökelmann. “Experimental and Numerical Simulation Study of Pre-Deformed Heavy Copper Wire Wedge Bonds.” In <i>Proceedings of the 47th International Symposium on Microelectronics (IMAPS)</i>, 289–94. San Diego, CA, US, 2014.","apa":"Unger, A., Sextro, W., Althoff, S., Eichwald, P., Meyer, T., Eacock, F., &#38; Brökelmann, M. (2014). Experimental and Numerical Simulation Study of Pre-Deformed Heavy Copper Wire Wedge Bonds. In <i>Proceedings of the 47th International Symposium on Microelectronics (IMAPS)</i> (pp. 289–294). San Diego, CA, US.","bibtex":"@inproceedings{Unger_Sextro_Althoff_Eichwald_Meyer_Eacock_Brökelmann_2014, place={San Diego, CA, US}, title={Experimental and Numerical Simulation Study of Pre-Deformed Heavy Copper Wire Wedge Bonds}, booktitle={Proceedings of the 47th International Symposium on Microelectronics (IMAPS)}, author={Unger, Andreas and Sextro, Walter and Althoff, Simon and Eichwald, Paul and Meyer, Tobias and Eacock, Florian and Brökelmann, Michael}, year={2014}, pages={289–294} }","mla":"Unger, Andreas, et al. “Experimental and Numerical Simulation Study of Pre-Deformed Heavy Copper Wire Wedge Bonds.” <i>Proceedings of the 47th International Symposium on Microelectronics (IMAPS)</i>, 2014, pp. 289–94.","short":"A. Unger, W. Sextro, S. Althoff, P. Eichwald, T. Meyer, F. Eacock, M. Brökelmann, in: Proceedings of the 47th International Symposium on Microelectronics (IMAPS), San Diego, CA, US, 2014, pp. 289–294."},"page":"289-294","place":"San Diego, CA, US","year":"2014","date_created":"2019-05-20T13:35:09Z","author":[{"first_name":"Andreas","full_name":"Unger, Andreas","last_name":"Unger"},{"first_name":"Walter","last_name":"Sextro","full_name":"Sextro, Walter","id":"21220"},{"first_name":"Simon","full_name":"Althoff, Simon","last_name":"Althoff"},{"last_name":"Eichwald","full_name":"Eichwald, Paul","first_name":"Paul"},{"last_name":"Meyer","full_name":"Meyer, Tobias","first_name":"Tobias"},{"first_name":"Florian","full_name":"Eacock, Florian","last_name":"Eacock"},{"full_name":"Brökelmann, Michael","last_name":"Brökelmann","first_name":"Michael"}],"date_updated":"2020-05-07T05:33:47Z","title":"Experimental and Numerical Simulation Study of Pre-Deformed Heavy Copper Wire Wedge Bonds"},{"user_id":"55222","department":[{"_id":"151"}],"_id":"9745","type":"journal_article","status":"public","author":[{"first_name":"Bo","last_name":"Fu","full_name":"Fu, Bo"},{"first_name":"Chao","full_name":"Li, Chao","last_name":"Li"},{"full_name":"Zhang, Jianming","last_name":"Zhang","first_name":"Jianming"},{"last_name":"Huang","full_name":"Huang, Zhenwei","first_name":"Zhenwei"},{"last_name":"Hemsel","full_name":"Hemsel, Tobias","id":"210","first_name":"Tobias"}],"volume":57,"date_updated":"2022-01-06T07:04:19Z","doi":"10.3938/jkps.57.929","publication_identifier":{"issn":["1948-5719"]},"citation":{"chicago":"Fu, Bo, Chao Li, Jianming Zhang, Zhenwei Huang, and Tobias Hemsel. “Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods.” <i>Journal of Korean Physical Society</i> 57, no. 4 (2010): 929. <a href=\"https://doi.org/10.3938/jkps.57.929\">https://doi.org/10.3938/jkps.57.929</a>.","ieee":"B. Fu, C. Li, J. Zhang, Z. Huang, and T. Hemsel, “Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods,” <i>Journal of Korean Physical Society</i>, vol. 57, no. 4, p. 929, 2010.","ama":"Fu B, Li C, Zhang J, Huang Z, Hemsel T. Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods. <i>Journal of Korean Physical Society</i>. 2010;57(4):929. doi:<a href=\"https://doi.org/10.3938/jkps.57.929\">10.3938/jkps.57.929</a>","apa":"Fu, B., Li, C., Zhang, J., Huang, Z., &#38; Hemsel, T. (2010). Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods. <i>Journal of Korean Physical Society</i>, <i>57</i>(4), 929. <a href=\"https://doi.org/10.3938/jkps.57.929\">https://doi.org/10.3938/jkps.57.929</a>","bibtex":"@article{Fu_Li_Zhang_Huang_Hemsel_2010, title={Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods}, volume={57}, DOI={<a href=\"https://doi.org/10.3938/jkps.57.929\">10.3938/jkps.57.929</a>}, number={4}, journal={Journal of Korean Physical Society}, author={Fu, Bo and Li, Chao and Zhang, Jianming and Huang, Zhenwei and Hemsel, Tobias}, year={2010}, pages={929} }","short":"B. Fu, C. Li, J. Zhang, Z. Huang, T. Hemsel, Journal of Korean Physical Society 57 (2010) 929.","mla":"Fu, Bo, et al. “Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods.” <i>Journal of Korean Physical Society</i>, vol. 57, no. 4, 2010, p. 929, doi:<a href=\"https://doi.org/10.3938/jkps.57.929\">10.3938/jkps.57.929</a>."},"intvolume":"        57","page":"929","language":[{"iso":"eng"}],"keyword":["Piezoelectric langevin transducer","Transfer matrix method","Four (six)-pole element description","Pre-stressed bolt"],"publication":"Journal of Korean Physical Society","abstract":[{"text":"In the modeling of piezoelectric Langevin transducers using usual transfer matrix methods, some simplifications have been adopted. This leads to reduction of the model quality. A mixed transfer matrix method is employed in the modeling of Langevin transducers, where the pre-stressed bolt is modeled as a separate four-pole element, which is connected to other elements in parallel. Based on the mixed transfer matrix method, the four (six)-pole element description of the piezoelectric Langevin transducer is built up and the total transfer matrix relation is derived. The resonance frequencies of the transducer are calculated and then measured using the impedance analyzer (HP4192). Experimental result shows that the mixed transfer matrix method has better modeling quality than the usual transfer matrix method for the vibration analysis of piezoelectric Langevin transducers.","lang":"eng"}],"date_created":"2019-05-13T09:40:42Z","title":"Modeling of Piezoelectric Langevin Transducers by Using Mixed Transfer Matrix Methods","issue":"4","quality_controlled":"1","year":"2010"},{"year":"2008","page":"324-327","citation":{"apa":"Bo, F., Ting, L., &#38; Hemsel, T. (2008). A simple pre-stress estimating method of langevin transducers. In <i>Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium on</i> (pp. 324–327). <a href=\"https://doi.org/10.1109/SPAWDA.2008.4775801\">https://doi.org/10.1109/SPAWDA.2008.4775801</a>","bibtex":"@inproceedings{Bo_Ting_Hemsel_2008, title={A simple pre-stress estimating method of langevin transducers}, DOI={<a href=\"https://doi.org/10.1109/SPAWDA.2008.4775801\">10.1109/SPAWDA.2008.4775801</a>}, booktitle={Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium on}, author={Bo, Fu and Ting, Li and Hemsel, Tobias}, year={2008}, pages={324–327} }","short":"F. Bo, L. Ting, T. Hemsel, in: Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium On, 2008, pp. 324–327.","mla":"Bo, Fu, et al. “A Simple Pre-Stress Estimating Method of Langevin Transducers.” <i>Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium On</i>, 2008, pp. 324–27, doi:<a href=\"https://doi.org/10.1109/SPAWDA.2008.4775801\">10.1109/SPAWDA.2008.4775801</a>.","ama":"Bo F, Ting L, Hemsel T. A simple pre-stress estimating method of langevin transducers. In: <i>Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium On</i>. ; 2008:324-327. doi:<a href=\"https://doi.org/10.1109/SPAWDA.2008.4775801\">10.1109/SPAWDA.2008.4775801</a>","chicago":"Bo, Fu, Li Ting, and Tobias Hemsel. “A Simple Pre-Stress Estimating Method of Langevin Transducers.” In <i>Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium On</i>, 324–27, 2008. <a href=\"https://doi.org/10.1109/SPAWDA.2008.4775801\">https://doi.org/10.1109/SPAWDA.2008.4775801</a>.","ieee":"F. Bo, L. Ting, and T. Hemsel, “A simple pre-stress estimating method of langevin transducers,” in <i>Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium on</i>, 2008, pp. 324–327."},"date_updated":"2022-01-06T07:04:16Z","date_created":"2019-04-29T11:16:13Z","author":[{"first_name":"Fu","last_name":"Bo","full_name":"Bo, Fu"},{"first_name":"Li","full_name":"Ting, Li","last_name":"Ting"},{"id":"210","full_name":"Hemsel, Tobias","last_name":"Hemsel","first_name":"Tobias"}],"title":"A simple pre-stress estimating method of langevin transducers","doi":"10.1109/SPAWDA.2008.4775801","publication":"Piezoelectricity, Acoustic Waves, and Device Applications, 2008. SPAWDA 2008. Symposium on","type":"conference","abstract":[{"text":"A simple pre-stress estimate method of Langevin transducers is studied. The measurement setup consists of a capacitor, an impedance converter and a voltmeter. Based on the piezoelectric equation and the basic circuit theory, the mathematical expression between the pre-stress and the voltage across the capacitor is derived. The pre-stress level can then be calculated out of the measurement of the capacitor voltage. In order to evaluate the precision of this method, a force washer is used to measure the pre-stress of the Langevin transducer. The result shows the pre-stress level obtained from this method is 30-40\\% higher than the pre-stress level measured by the force washer. This method is simple and can be used to estimate the pre-stress of various Langevin transducers. The precision of this method can be raised if d33 is identified under different pre-stress levels.","lang":"eng"}],"status":"public","_id":"9568","department":[{"_id":"151"}],"user_id":"55222","keyword":["capacitors","impedance convertors","piezoelectric transducers","stress analysis","Langevin transducers","basic circuit theory","capacitor","impedance converter","piezoelectric equation","pre-stress estimating method","voltmeter","Capacitors","Educational institutions","Equations","Force measurement","Impedance measurement","Manufacturing","Mechatronics","Piezoelectric transducers","Voltage","Voltmeters","Langevin transducer","capacitor","piezoelectric element","pre-stress"],"language":[{"iso":"eng"}]}]