@article{30963,
  abstract     = {{<jats:title>Abstract</jats:title><jats:p>In this paper, a study based on experimental and numerical simulations is performed to analyze fatigue cracks in clinched joints. An experimental investigation is conducted to determine the failure modes of clinched joints under cyclic loading at different load amplitudes with single-lap shear tests. In addition, numerical FEM simulations of clinching process and subsequent shear loading are performed to support the experimental investigations by analyzing the state of stresses at the location of failure. An attempt is made to explain the location of crack initiation in the experiments using evaluation variables such as contact shear stress and maximum principal stress.</jats:p>}},
  author       = {{Ewenz, Lars and Bielak, Christian Roman and Otroshi, Mortaza and Bobbert, Mathias and Meschut, Gerson and Zimmermann, Martina}},
  issn         = {{0944-6524}},
  journal      = {{Production Engineering}},
  keywords     = {{Industrial and Manufacturing Engineering, Mechanical Engineering}},
  number       = {{2-3}},
  pages        = {{305--313}},
  publisher    = {{Springer Science and Business Media LLC}},
  title        = {{{Numerical and experimental identification of fatigue crack initiation sites in clinched joints}}},
  doi          = {{10.1007/s11740-022-01124-z}},
  volume       = {{16}},
  year         = {{2022}},
}

@article{34069,
  author       = {{Schramm, Britta and Martin, Sven and Steinfelder, Christian and Bielak, Christian Roman and Brosius, Alexander and Meschut, Gerson and Tröster, Thomas and Wallmersperger, Thomas and Mergheim, Julia}},
  issn         = {{2666-3309}},
  journal      = {{Journal of Advanced Joining Processes}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, Engineering (miscellaneous), Chemical Engineering (miscellaneous)}},
  publisher    = {{Elsevier BV}},
  title        = {{{A Review on the Modeling of the Clinching Process Chain - Part I: Design Phase}}},
  doi          = {{10.1016/j.jajp.2022.100133}},
  volume       = {{6}},
  year         = {{2022}},
}

@article{34068,
  author       = {{Schramm, Britta and Friedlein, Johannes and Gröger, Benjamin and Bielak, Christian Roman and Bobbert, Mathias and Gude, Maik and Meschut, Gerson and Wallmersperger, Thomas and Mergheim, Julia}},
  issn         = {{2666-3309}},
  journal      = {{Journal of Advanced Joining Processes}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, Engineering (miscellaneous), Chemical Engineering (miscellaneous)}},
  publisher    = {{Elsevier BV}},
  title        = {{{A Review on the Modeling of the Clinching Process Chain - Part II: Joining Process}}},
  doi          = {{10.1016/j.jajp.2022.100134}},
  year         = {{2022}},
}

@article{29951,
  abstract     = {{The components of a body in white consist of many individual thin-walled sheet metal parts, which usually are manufactured in deep-drawing processes. In general, the conditions in a deep-drawing process change due to changing tribology conditions, varying degrees of spring back, or scattering material properties in the sheet blanks, which affects the resulting pre-strain. Mechanical joining processes, especially clinching, are influenced by these process-related pre-strains. The final geometric shape of a clinched joint is affected to a significant level by the prior material deformation when joining with constant process parameters. That leads to a change in the stiffness and force transmission in the clinched joint due to the different geometric dimensions, such as interlock, neck thickness and bottom thickness, which directly affect the load bearing capacity. Here, the influence of the pre-straining in the deep drawing process on the force distribution in clinch points in an automotive assembly is investigated by finite-element models numerically. In further studies, the results are implemented in an optimization tool for designing clinched components. The methodology starts with a pre-straining of metal sheets. This step is followed by 2D rotationally symmetric forming simulations of the joining process. The resulting mesh of each forming simulation is rotated and 3D models are obtained. The clinched joint solid model with pre-strains is used further to determine the joint stiffnesses. With the simulation of the same test set-up with an equivalent point-connector model, the equivalent stiffness for each pre-strain combination is determined. Simulations are performed on a clinched component to assess the influence of pre-strain and sheet thinning on the clinched joint loadings by using the equivalent stiffnesses. The investigations clearly show that for the selected component, the loadings at the clinch points are dependent on the sheet thinning and the stiffnesses due to pre-strain. The magnitude of the influence varies depending on the quantity considered. For example, the shear force is more sensitive to the joint stiffness than to the sheet thinning.</jats:p>}},
  author       = {{Martin, Sven and Bielak, Christian Roman and Bobbert, Mathias and Tröster, Thomas and Meschut, Gerson}},
  issn         = {{0944-6524}},
  journal      = {{Production Engineering}},
  keywords     = {{Industrial and Manufacturing Engineering, Mechanical Engineering}},
  publisher    = {{Springer Science and Business Media LLC}},
  title        = {{{Numerical investigation of the clinched joint loadings considering the initial pre-strain in the joining area}}},
  doi          = {{10.1007/s11740-021-01103-w}},
  year         = {{2022}},
}

@inproceedings{44269,
  abstract     = {{Semi-structural adhesive joints with hyperelastic polyurethane adhesives and large adhesive layer thicknesses enable the realization of innovative hybrid lightweight designs with fiber reinforced plastic (FRP) composites. The design of these adhesively bonded joints with complex mechanical behavior requires a valid and efficient method for computational service life prediction. In this paper, a submodel-based service strength analysis method for adhesively bonded hybrid structures is presented and validated on sub component fatigue tests. The submodel strategy is generalized by periodic boundary conditions to evaluate failure relevant stresses and thus fatigue life in advance and independently from the global structure analysis.}},
  author       = {{Tittmann, Karsten  and Koch, Ilja  and Çavdar, Serkan and Gude, Maik  and Meschut, Gerson}},
  booktitle    = {{Proceedings of the 20th European Conference on Composite Materials}},
  location     = {{Lausanne}},
  pages        = {{730--739}},
  title        = {{{Service strength analysis method for adhesively bonded hybrid structures under multiaxial loading}}},
  volume       = {{2}},
  year         = {{2022}},
}

@inproceedings{29856,
  author       = {{Jamei, Said and Döller, Norbert and Lossau, Sebastian and Beule, Felix and Al Trjman, Mohamad and Aubel, Tobias and Meschut, Gerson and Sommer, Daniel and Facciotto, Silvio and Droste, Alexander and Haufe, Andre and Helbig, Martin and Gleich, Henning and Kose, Kim}},
  booktitle    = {{22. Kolloquium: Gemeinsame Forschung in der Klebtechnik}},
  title        = {{{DigiBody - Digitale Prozesskette zur Abbildung und Optimierung der Fügetechnik im Rohbau }}},
  year         = {{2022}},
}

@inproceedings{42239,
  author       = {{Klöppel, Thomas and Haufe, Andre and Helbig, Martin and Liebold, Christian and Beule, Felix and Al Trjman, Mohamad and Aubel, Tobias and Meschut, Gerson and Jamei, Said and Fürle, Fabian and Lossau, Sebastian and Droste, Alexander and Gleich, Henning and Kose, Kim and Sommer, Daniel and Facciotto, Silvio}},
  booktitle    = {{4a-Technologietage 2022}},
  location     = {{Schladming}},
  title        = {{{A new viscoelastic-viscoplastic constitutive formulation in LS-DYNA to model adhesives during the complete manufacturing-crashworthiness process chain}}},
  year         = {{2022}},
}

@article{30951,
  author       = {{Schmolke, Tobias and Teutenberg, Dominik and Meschut, Gerson}},
  issn         = {{0143-7496}},
  journal      = {{International Journal of Adhesion and Adhesives}},
  keywords     = {{Polymers and Plastics, General Chemical Engineering, Biomaterials}},
  publisher    = {{Elsevier BV}},
  title        = {{{Development of a test method for investigating the leak tightness of hybrid joined battery housing connections}}},
  doi          = {{10.1016/j.ijadhadh.2022.103171}},
  volume       = {{117}},
  year         = {{2022}},
}

@article{30394,
  author       = {{Hecht, Matthias and Baumgartner, Jörg and Tews, Karina and Çavdar, Serkan and Meschut, Gerson}},
  issn         = {{2452-3216}},
  journal      = {{Procedia Structural Integrity}},
  keywords     = {{General Engineering, Energy Engineering and Power Technology}},
  pages        = {{251--259}},
  publisher    = {{Elsevier BV}},
  title        = {{{Fatigue strength of adhesively butt-bonded hollow cylinders under multiaxial loading with constant and variable amplitudes}}},
  doi          = {{10.1016/j.prostr.2022.03.026}},
  volume       = {{38}},
  year         = {{2022}},
}

@inproceedings{32389,
  author       = {{Rossel, Moritz Sebastian and Meschut, Gerson}},
  location     = {{Toronto}},
  title        = {{{Increasing the Prediction Quality of Clinching Process Simulation with Extensible Die by Means of Friction Modeling as a Function of the Local Joining Process Parameters}}},
  year         = {{2022}},
}

@article{51192,
  abstract     = {{<jats:p>
Destructive micrograph analysis (MA) is the standard method for the assessment of clinched joints. However, during the joint preparation for the MA, geometric features of the joint can change due to elastic effects and closing cracks. X-ray computed tomography (CT) is a promising alternative to investigate the joint non-estructively. However, if the material properties of similar joining partners are the same, the CT is not able to correctly resolve surfaces in the joint that are close to or pressing onto each other. These surfaces are relevant for the determination of characteristic dimensions such as neck thickness and undercut. By placing a thin, highly radiopaque tin layer between the joining partners, the interfacial area in the reconstructed volume can be highlighted. In this work, a method for the localisation of the tin layer inside the joint as well as threshold value procedures for the outer joint contour in cross section images are investigated. The measured characteristic dimensions are compared with measured values from MA of the same samples and of samples without tin layer. In addition, possible effects of the tin layer on the joining point characteristics as well as problems of the MA are discussed.
</jats:p>}},
  author       = {{Busch, Matthias and Köhler, Daniel and Hausotte, Tino and Kupfer, Robert and Troschitz, Juliane and Gude, Maik}},
  issn         = {{1435-4934}},
  journal      = {{e-Journal of Nondestructive Testing}},
  number       = {{12}},
  publisher    = {{NDT.net}},
  title        = {{{Approach to Determine the Characteristic Dimensions of Clinched Joints by Industrial X-ray Computed Tomography}}},
  doi          = {{10.58286/27519}},
  volume       = {{27}},
  year         = {{2022}},
}

@inproceedings{51191,
  abstract     = {{Zur Qualitätssicherung von Clinchpunkten werden häufig ex-situ Methoden, wie etwa Schliffbildanalysen, eingesetzt. Diese ermöglichen jedoch nicht die Berücksichtigung von Phänomenen, die während der Belastung auftreten, da sich nach der Entlastung elastische Deformationen zurückbilden und Risse wieder schließen. Dagegen kann mit der in-situ Computertomographie (CT) der innere Deformationszustand des Clinchpunkts, z.B. während eines Scherzugversuchs, untersucht werden. Hierbei ist es für artgleiche Werkstoffe aufgrund der hohen Pressungen im Clinchpunkt schwierig, die Trennfläche zwischen den Fügepartnern im CT-Scan zu erkennen. Daher wird eine radioopake Zwischenschicht aus Zinn in die Trennfläche eingebracht. In dieser Arbeit wird der Einfluss der Zwischenschicht auf die in-situ CT-Scherzugprüfung untersucht. Hierzu werden sowohl Kraft-Verlängerungs-Kurven als auch die Geometrie der Clinchpunkte während der Belastung verglichen.}},
  author       = {{Köhler, Daniel and Kupfer, Robert and Troschitz, Juliane and Gude, Maik}},
  booktitle    = {{Tagungsband zur Werkstoffprüfung 2022}},
  editor       = {{Zimmermann, Martina}},
  location     = {{Dresden}},
  title        = {{{Untersuchung zum Einfluss radioopaker Zwischenschichten bei der in-situ CT geclinchter Verbindungen}}},
  year         = {{2022}},
}

@inbook{51195,
  author       = {{Köhler, Daniel and Kupfer, Robert and Troschitz, Juliane and Gude, Maik}},
  booktitle    = {{The Minerals, Metals &amp; Materials Series}},
  isbn         = {{9783031062117}},
  issn         = {{2367-1181}},
  publisher    = {{Springer International Publishing}},
  title        = {{{Clinching in In Situ CT—A Novel Validation Method for Mechanical Joining Processes}}},
  doi          = {{10.1007/978-3-031-06212-4_75}},
  year         = {{2022}},
}

@article{51197,
  abstract     = {{<jats:p>Clinching is a cost efficient method for joining components in series production. To assure the clinch point’s quality, the force displacement curve during clinching or the bottom thickness are monitored. The most significant geometrical characteristics of the clinch point, neck thickness and undercut, are usually tested destructively by microsectioning. However, micrograph preparation goes ahead with a resetting of elastic deformations and crack-closing after unloading. To generate a comprehensive knowledge of the clinch point’s inner geometry under load, in-situ computed tomography (CT) and acoustic testing (TDA) can be combined. While the TDA is highly sensitive to the inner state of the clinch point, it could detect critical events like crack development during loading. If such events are indicated, the loading process is stopped and a stepped in-situ CT of the following crack and deformation development is performed. In this paper, the concept is applied to the process of clinching itself, providing a detailed three-dimensional insight in the development of the joining zone. A test set-up is used which allows a stepwise clinching of two aluminium sheets EN AW 6014. Furthermore, this set-up is positioned within a CT system. In order to minimize X-ray absorption, a beryllium cylinder is used within the set-up frame and clinching tools are made from Si3N4. The actuator and sensor necessary for the TDA are integrated in the set-up. In regular process steps, the clinching process is interrupted in order to perform a TDA and a CT scan. In order to enhance the visibility of the interface, a thin tin layer is positioned between the sheets prior clinching. It is shown, that the test-set up allows a monitoring of the dynamic behaviour of the specimen during clinching while the CT scans visualize the inner geometry and material flow non-destructively.</jats:p>}},
  author       = {{Köhler, Daniel and Stephan, Richard and Kupfer, Robert and Troschitz, Juliane and Brosius, Alexander and Gude, Maik}},
  issn         = {{1662-9795}},
  journal      = {{Key Engineering Materials}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}},
  pages        = {{1489--1497}},
  publisher    = {{Trans Tech Publications, Ltd.}},
  title        = {{{Investigations on Combined &lt;i&gt;In Situ&lt;/i&gt; CT and Acoustic Analysis during Clinching}}},
  doi          = {{10.4028/p-32330d}},
  volume       = {{926}},
  year         = {{2022}},
}

@article{30847,
  abstract     = {{Mechanical joining technologies like self-piercing riveting are gaining importance with regard to environmental protection, as they enable multi-material design and lightweight construction. A new approach is the use of high nitrogen steel as rivet material, which allows to omit the usually necessary heat treatment and coating and thus leads to a shortening of the process chain. Due to the high strain hardening, however, high tool loads must be expected. Thus, appropriate forming strategies are needed. Within this contribution, the influence of applying different temperatures for each forming stage in a two-stage rivet forming process using the high nitrogen steel 1.3815 is investigated. The findings provide a basic understanding of the influence of the temperature management when forming high nitrogen steel. For this purpose, the rivets are not formed at the same temperature in each stage, but an elevated temperature is applied selectively. Different process routes are investigated. First, cups are manufactured in stage 1 at room temperature, followed by stage 2 at 200°C. Second, cups are formed in stage 1 at 200°C and used for stage 2 at room temperature. By comparing the findings with results when applying the same temperature in both stages, it is shown that the temperature during the first forming operation has an effect on the forming behaviour during the second forming stage. The required forming forces and the resulting rivet hardness can be influenced by process-adapted temperature application. Furthermore, the causes for the temperature impact on the residual cup thickness in stage 1 are evaluated by a cause and effect analysis, which provides a deeper process understanding. The thermal expansion of the tool and the billet as well as the improved forming behaviour at 200°C are identified as the main influencing causes on the achieved residual cup thickness.}},
  author       = {{Kuball, Clara-Maria and Uhe, Benedikt and Meschut, Gerson and Merklein, Marion}},
  issn         = {{1464-4207}},
  journal      = {{Proceedings of the Institution of Mechanical Engineers Part L-Journal of Materials-Design and Applications}},
  pages        = {{1--17}},
  title        = {{{Process-adapted temperature application within a two-stage rivet forming process for high nitrogen steel}}},
  doi          = {{10.1177/14644207211068693}},
  year         = {{2022}},
}

@article{52612,
  abstract     = {{<jats:p>During resistance spot welding of zinc-coated advanced high-strength steels (AHSSs) for automotive production, liquid metal embrittlement (LME) cracking may occur in the event of a combination of various unfavorable influences. In this study, the interactions of different welding current levels and weld times on the tendency for LME cracking in third-generation AHSSs were investigated. LME manifested itself as high-penetration cracks around the circumference of the spot welds for welding currents closely below the expulsion limit. At the same time, the observed tendency for LME cracking showed no direct correlation with the overall heat input of the investigated welding processes. To identify a reliable indicator of the tendency for LME cracking, the local strain rate at the origin of the observed cracks was analyzed over the course of the welding process via finite element simulation. While the local strain rate showed a good correlation with the process-specific LME cracking tendency, it was difficult to interpret due to its discontinuous course. Therefore, based on the experimental measurement of electrode displacement during welding, electrode indentation velocity was proposed as a descriptive indicator for quantifying cracking tendency.</jats:p>}},
  author       = {{Böhne, Christoph and Meschut, Gerson and BIEGLER, MAX and RETHMEIER, MICHAEL}},
  issn         = {{0043-2296}},
  journal      = {{Welding Journal}},
  keywords     = {{Metals and Alloys, Mechanical Engineering, Mechanics of Materials}},
  number       = {{7}},
  pages        = {{197--207}},
  publisher    = {{American Welding Society}},
  title        = {{{The Influence of Electrode Indentation Rate on LME Formation during RSW}}},
  doi          = {{10.29391/2022.101.015}},
  volume       = {{101}},
  year         = {{2022}},
}

@article{25104,
  author       = {{Göddecke, Johannes and Meschut, Gerson and Damm, Jannis and Albiez, Matthias and Ummenhofer, Thomas}},
  issn         = {{1619-1919}},
  journal      = {{adhäsion KLEBEN & DICHTEN}},
  pages        = {{14--23}},
  publisher    = {{Springer Nature}},
  title        = {{{Dämpfungseigenschaften geklebter Verbindungen - Potenzialanalyse und Klebstoffcharakterisierung}}},
  doi          = {{https://doi.org/10.1007/s35145-021-0520-8}},
  year         = {{2021}},
}

@inproceedings{28443,
  author       = {{Rossel, Moritz Sebastian and Meschut, Gerson}},
  booktitle    = {{11. Fügetechnisches Gemeinschaftskolloquium}},
  title        = {{{Steigerung der Prognosegüte mechanischer Fügeprozesssimulationen durch den Einsatz einer fügespezifischen Reibmodellierung basierend auf einer experimentellen Parametrisierung}}},
  year         = {{2021}},
}

@article{28448,
  author       = {{Droß, M. and Heyser, Per and Meschut, Gerson and Hürkamp, A. and Dröder, K.}},
  issn         = {{2666-3309}},
  journal      = {{Journal of Advanced Joining Processes}},
  title        = {{{Fiber response to pin penetration in dry woven fabric using numerical analysis}}},
  doi          = {{10.1016/j.jajp.2021.100083}},
  year         = {{2021}},
}

@book{26649,
  abstract     = {{Within the scope of the research project, four new mechanical joining processes for the singlestage, pre-hole-free joining of FRP-FRP joints were further developed. For this purpose, the joining processes under consideration were first implemented on existing equipment at the research institute. Based on the successful adaptation of the joining processes, characteristics of the joints were documented by means of micrographs and observation of external characteristics, on the basis of which measures for process modification were derived. The process modifications were carried out on a process-specific basis for a selected GFRPGFRP joint. The aim was to improve the joint quality, in particular with regard to the reduction of laminate damage, by means of targeted element and tool development in addition to the increase in process stability. Based on these results, a realistic suitability evaluation of the
joining methods was carried out with regard to process and manufacturing flexibility. As a result, two self-piercing riveting processes, which showed the greatest suitability potential, were examined in more detail to analyse the application limits. In the process, the joints were sampled on further material combinations with varied fibre and matrix systems. In addition, joints with adhesive were investigated, in which the influence of the adhesive viscosity on the joint properties was analysed. The joint properties of the new joining method were then comprehensively determined by tensile tests under quasi-static, cyclic loads. Finally, the behaviour of the optimised joints under corrosive load was characterised in the salt spray test. Through the targeted process modifications in this project, the FRP-FRP joints can be joined
with less damage, enabling improved joint quality in the FRP-based components.}},
  author       = {{Han, Daxin and Meschut, Gerson}},
  isbn         = {{978-3-86776-618-0}},
  title        = {{{Mechanisches Fügen von FKV-FKV-Verbindungen}}},
  year         = {{2021}},
}