@inproceedings{59878,
  abstract     = {{<jats:p>Abstract. In the development of advanced lightweight automotive solutions, self-piercing riveting (SPR) offers the possibility of joining multi-material structures to fulfil a wide variety of requirements. With regard to the entire process chain, production-related pre-deformations of the parts to be joined can influence the geometric shape and load capacity of SPR joints. Various studies have investigated the influence of pre-stretched sheet materials, in the sense of pre-drawing processes, on the formation of SPR joints. The impact of pre-stretching sheet metals on the formation of their geometrical characteristics and the shear-tensile strength of SPR processes was observed [1]. Pre-rolled semi-finished products are also joined together in mixed material automotive structures, e.g. tailor rolled blanks. This work aims to investigate the influence of pre-rolled joining parts on the geometric formation and load-carrying capacity of SPR joints. For this purpose, sheets of metal are cold-formed using a rolling process to induce a defined strain-hardening state in the material and then joined in various combinations. As the degree of deformation increases, the rolling of samples can lead to minimal accumulation of damage in the sheet materials, which can influence the joint behaviour. The rolling process, as well as the subsequent joining process, are also investigated by FEM. The influence of pre-rolled semi-finished products on the strength of the SPR joints is investigated.</jats:p>}},
  author       = {{Schlichter, Malte Christian and Harabati, Özcan and Ludwig, Jean-Patrick and Böhnke, Max and Bielak, Christian Roman and Bobbert, Mathias and Meschut, Gerson}},
  booktitle    = {{Materials Research Proceedings}},
  issn         = {{2474-395X}},
  publisher    = {{Materials Research Forum LLC}},
  title        = {{{Experimental and numerical investigation of the influence of rolling-induced sheet metal deformation on SPR joints}}},
  doi          = {{10.21741/9781644903599-148}},
  volume       = {{54}},
  year         = {{2025}},
}

@inproceedings{60977,
  abstract     = {{In the development of advanced lightweight automotive solutions, self-piercing riveting (SPR) offers the possibility of joining multi-material structures to fulfil a wide variety of requirements. With regard to the entire process chain, production-related pre-deformations of the parts to be joined can influence the geometric shape and load capacity of SPR joints. Various studies have investigated the influence of pre-stretched sheet materials, in the sense of pre-drawing processes, on the formation of SPR joints. The impact of pre-stretching sheet metals on the formation of their geometrical characteristics and the shear-tensile strength of SPR processes was observed [1]. Pre-rolled semi-finished products are also joined together in mixed material automotive structures, e.g. tailor rolled blanks. This work aims to investigate the influence of pre-rolled joining parts on the geometric formation and load-carrying capacity of SPR joints. For this purpose, sheets of metal are cold-formed using a rolling process to induce a defined strain-hardening state in the material and then joined in various combinations. As the degree of deformation increases, the rolling of samples can lead to minimal accumulation of damage in the sheet materials, which can influence the joint behaviour. The rolling process, as well as the subsequent joining process, are also investigated by FEM. The influence of pre-rolled semi-finished products on the strength of the SPR joints is investigated.</jats:p>}},
  author       = {{Schlichter, Malte Christian and Harabati, Özcan and Ludwig, Jean-Patrick and Böhnke, Max and Bielak, Christian Roman and Bobbert, Mathias and Meschut, Gerson}},
  booktitle    = {{Materials Research Proceedings}},
  issn         = {{2474-395X}},
  publisher    = {{Materials Research Forum LLC}},
  title        = {{{Experimental and numerical investigation of the influence of rolling-induced sheet metal deformation on SPR joints}}},
  doi          = {{10.21741/9781644903599-148}},
  volume       = {{54}},
  year         = {{2025}},
}

@inproceedings{60978,
  abstract     = {{The present study is an experimental analysis of the influence of pre-forming on the failure behaviour of clinched specimens under quasi-static and cyclic loading conditions. In this context, the geometric formation of the clinched joints is taken into account, with regard to the loading behaviour. The study also includes a comparison of the failure behaviour of quasi-static and cyclic tested specimen. Testing is done on non-pre-deformed and pre-deformed specimens. For this purpose, experimental investigations are carried out on two material combinations consisting of HCT590X steel sheet and EN AW-6014 T4 aluminium sheet. The focus is on the fatigue analysis of the clinched joints. The aim is to identify the failure modes under cyclic loading and the crack formation with regard to forming operations prior to the joining process. The investigations show that the cyclic load-bearing behaviour of the HCT590X joints is reduced by introducing a plastic pre-deformation of the to be joined parts.</jats:p>}},
  author       = {{Schlichter, Malte Christian and Harabati, Özcan and Böhnke, Max and Bielak, Christian Roman and Bobbert, Mathias and Meschut, Gerson}},
  booktitle    = {{Materials Research Proceedings}},
  issn         = {{2474-395X}},
  publisher    = {{Materials Research Forum LLC}},
  title        = {{{Investigation on manufacturing-induced pre-deformation on the fatigue behaviour of clinched joints}}},
  doi          = {{10.21741/9781644903551-16}},
  volume       = {{52}},
  year         = {{2025}},
}

@inproceedings{60002,
  abstract     = {{This study focuses on damage modeling across different mechanical joining processes within a process chain, specifically using clinching and self-pierce riveting (SPR). The aim is to apply a comprehensive model that captures the damage mechanisms and interactions in these technologies, optimizing them for enhanced performance and durability of aluminum joints. A GISSMO damage model was utilized, based on the stress states occurring during the joining process and a newly introduced damage testing method. This model was applied to both clinching and SPR processes. A detailed analysis of the stress states provided insights into their effect on the material. By incorporating these insights into the GISSMO model, improved accuracy in damage prediction was achieved. The model's application to clinching and SPR demonstrated its effectiveness in optimizing aluminum joint performance and durability, ensuring that the processes can be finely tuned to minimize damage and enhance joint quality.</jats:p>}},
  author       = {{Harabati, Özcan and Bielak, Christian Roman and Böhnke, Max and Schlichter, Malte Christian and Brockmeier, Marc and Bobbert, Mathias and Meschut, Gerson}},
  booktitle    = {{Materials Research Proceedings}},
  issn         = {{2474-395X}},
  publisher    = {{Materials Research Forum LLC}},
  title        = {{{Cross-process damage modeling: A process-chain case study of clinching and self-pierced riveting for aluminum connections}}},
  doi          = {{10.21741/9781644903551-19}},
  volume       = {{52}},
  year         = {{2025}},
}

@article{59584,
  author       = {{Friedlein, Johannes and Lüder, Stephan and Kalich, Jan and Schmale, Hans Christian and Böhnke, Max and Schlichter, Malte Christian and Bobbert, Mathias and Meschut, Gerson and Steinmann, Paul and Mergheim, Julia}},
  issn         = {{2666-3309}},
  journal      = {{Journal of Advanced Joining Processes}},
  publisher    = {{Elsevier BV}},
  title        = {{{Application of stress-state-dependent ductile damage and failure model to clinch joining for a wide range of tool and material combinations}}},
  doi          = {{10.1016/j.jajp.2025.100299}},
  volume       = {{11}},
  year         = {{2025}},
}

@inproceedings{58384,
  abstract     = {{<jats:p>Abstract. Structures made of aluminum die casting are being used in increasing quantities as well as component sizes for various applications. Due to the size of the components, heat treatment of the cast parts following the casting process is omitted in order to meet dimensional accuracy requirements and reduce production costs. From such an approach, challenges arise with regard to the mechanical joining of these aluminum die-cast structures. On one hand, the absence of heat treatment results in a general decrease in ductility. On the other hand, the increasing size of the components introduces process-related tolerances regarding the quality of the casting, including the presence of air or gas inclusions, and significant variations in ductility within the component. These factors present challenges for mechanical joining technologies, such as the potential risk of crack-related defects during the joining process. For the robust mechanical joining of such materials, the development and validation of suitable joining strategies for aluminum die cast components is presented in this paper. A preparatory step involving localized heat treatment in the joining area is implemented to enhance the suitability of the casting material for mechanical joining. The objective is to generate an improved ductility state in the aluminum die casting material, enabling crack-free joining through self-pierce riveting. Additionally, the formability of the aluminum die casting material is characterized using a specially developed ductility testing method. This allows the prediction of potential crack-related defects during mechanical joining. The methods described are developed using the AlSi10MnMg material in its as-cast state and applied to the self-pierce riveting process. </jats:p>}},
  author       = {{Kraus, Christian and Böhnke, Max and Drossel, Welf-Guntram and Meschut, Gerson}},
  booktitle    = {{Materials Research Proceedings}},
  issn         = {{2474-395X}},
  location     = {{Toulouse}},
  publisher    = {{Materials Research Forum LLC}},
  title        = {{{Development of new strategies for the mechanical joining of components made of aluminum die casting}}},
  doi          = {{10.21741/9781644903131-190}},
  volume       = {{41}},
  year         = {{2024}},
}

@article{57742,
  author       = {{Böhnke, Max and Bielak, Christian Roman and Beck, Robert and Bobbert, Mathias and Meschut, Gerson}},
  issn         = {{2223-7690}},
  journal      = {{Friction}},
  publisher    = {{Tsinghua University Press}},
  title        = {{{Development of a friction model for the numerical simulation of clinching processes}}},
  doi          = {{10.26599/frict.2025.9441052}},
  year         = {{2024}},
}

@article{59585,
  abstract     = {{<jats:p>Similar to bulk metal forming, clinch joining is characterised by large plastic deformations and a variety of different 3D stress states, including severe compression. However, inherent to plastic forming is the nucleation and growth of defects, whose detrimental effects on the material behaviour can be described by continuum damage models and eventually lead to material failure. As the damage evolution strongly depends on the stress state, a stress-state-dependent model is utilised to correctly track the accumulation. To formulate and parameterise this model, besides classical experiments, so-called modified punch tests are also integrated herein to enhance the calibration of the failure model by capturing a larger range of stress states and metal-forming-specific loading conditions. Moreover, when highly ductile materials are considered, such as the dual-phase steel HCT590X and the aluminium alloy EN AW-6014 T4 investigated here, strong necking and localisation might occur prior to fracture. This can alter the stress state and affect the actual strain at failure. This influence is captured by coupling plasticity and damage to incorporate the damage-induced softening effect. Its relative importance is shown by conducting inverse parameter identifications to determine damage and failure parameters for both mentioned ductile metals based on up to 12 different experiments.</jats:p>}},
  author       = {{Friedlein, Johannes and Böhnke, Max and Schlichter, Malte Christian and Bobbert, Mathias and Meschut, Gerson and Mergheim, Julia and Steinmann, Paul}},
  issn         = {{2504-4494}},
  journal      = {{Journal of Manufacturing and Materials Processing}},
  number       = {{4}},
  publisher    = {{MDPI AG}},
  title        = {{{Material Parameter Identification for a Stress-State-Dependent Ductile Damage and Failure Model Applied to Clinch Joining}}},
  doi          = {{10.3390/jmmp8040157}},
  volume       = {{8}},
  year         = {{2024}},
}

@inproceedings{43090,
  abstract     = {{<jats:p>Abstract. The application of the mechanical joining process clinching allows the assembly of different sheet metal materials with a wide range of material thickness configurations, which is of interest for lightweight multi-material structures. In order to be able to predict the clinched joint properties as a function of the individual manufacturing steps, current studies focus on numerical modeling of the entire clinching process chain. It is essential to be able to take into account the influence of the joining process-induced damage on the load-bearing capacity of the joint during the loading phase. This study presents a numerical damage accumulation in the clinching process based on an implemented Hosford-Coulomb failure model using a 3D clinching process model applied on the aluminum alloy EN AW-6014 in temper T4. A correspondence of the experimentally determined failure location with the element of the highest numerically determined damage accumulation is shown. Moreover, the experimentally determined failure behavior is predicted to be in agreement in the numerical loading simulation with transferred pre-damage from the process simulation. </jats:p>}},
  author       = {{Bielak, Christian Roman and Böhnke, Max and Friedlein, Johannes and Bobbert, Mathias and Mergheim, Julia and Steinmann, Paul and Meschut, Gerson}},
  booktitle    = {{Materials Research Proceedings}},
  issn         = {{2474-395X}},
  publisher    = {{Materials Research Forum LLC}},
  title        = {{{Numerical analysis of failure modeling in clinching process chain simulation}}},
  doi          = {{10.21741/9781644902417-33}},
  year         = {{2023}},
}

@inproceedings{43462,
  abstract     = {{<jats:p>Abstract. In the numerical simulation of mechanical joining technologies such as clinching, the material modeling of the joining parts is of major importance. This includes modeling the damage and failure behavior of the materials in accordance with varying occurring stress states. This paper presents a calibration method of three different fracture models. The calibration of the models is done by use of experimental data from a modified punch test, tensile test and bulge test in order to map the occurring stress states from clinching processes and to precisely model the resulting failure behavior. Experimental investigations were carried out for an aluminum alloy  EN AW-6014 in temper T4 and compared with the simulative results generated in LS-DYNA. The comparison of force-displacement curves and failure initiation shows that the Hosford–Coulomb model predicts the failure behavior for the material used and the tests applied with the best accuracy. </jats:p>}},
  author       = {{Böhnke, Max and Bielak, Christian Roman and Friedlein, Johannes and Bobbert, Mathias and Mergheim, Julia and Steinmann, Paul and Meschut, Gerson}},
  booktitle    = {{Materials Research Proceedings}},
  issn         = {{2474-395X}},
  publisher    = {{Materials Research Forum LLC}},
  title        = {{{A calibration method for failure modeling in clinching process simulations}}},
  doi          = {{10.21741/9781644902417-34}},
  year         = {{2023}},
}

@inbook{52454,
  author       = {{Böhnke, Max and Bielak, Christian Roman and Bobbert, Mathias and Meschut, Gerson}},
  booktitle    = {{Lecture Notes in Mechanical Engineering}},
  isbn         = {{9783031413407}},
  issn         = {{2195-4356}},
  publisher    = {{Springer Nature Switzerland}},
  title        = {{{Experimental and Numerical Investigation of Clinched Joints Under Shear Tensile Loading at High Strain Rates}}},
  doi          = {{10.1007/978-3-031-41341-4_12}},
  year         = {{2023}},
}

@inproceedings{43463,
  author       = {{Friedlein, Johannes and Bielak, Christian Roman and Böhnke, Max and Bobbert, Mathias and Mergheim, Julia and Steinmann, Paul and Meschut, Gerson}},
  booktitle    = {{Materials Research Proceedings}},
  publisher    = {{Materials Research Forum LLC}},
  title        = {{{Influence of plastic orthotropy on clinching of sheet metal}}},
  doi          = {{10.21741/9781644902417-17 }},
  year         = {{2023}},
}

@inbook{52614,
  author       = {{Bielak, Christian Roman and Böhnke, Max and Bobbert, Mathias and Meschut, Gerson}},
  booktitle    = {{Lecture Notes in Mechanical Engineering}},
  isbn         = {{9783031413407}},
  issn         = {{2195-4356}},
  publisher    = {{Springer Nature Switzerland}},
  title        = {{{Numerical Investigation of the Coupled Friction Behavior in the Clinching Process Chain}}},
  doi          = {{10.1007/978-3-031-41341-4_15}},
  year         = {{2023}},
}

@article{32413,
  abstract     = {{Background. Clinching is a conventional cold forming process in which two or more sheets can be joined without auxiliary parts. A pre-forming of the parts to be joined, which is introduced by previous manufacturing steps, has an influence on the joining result. When considering the suitability for joining with regard to the formability of the materials, the influence of the preforming steps must be taken into account. The influences of strain hardening and sheet thickness on the joining properties must be investigated. In this context, a Finite Element Method (FEM) based metamodel analysis of the clinching process was carried out in [1] to investigate the robustness of the clinching process with respect to the different material pre-strains. In [2], the method was extended to the load bearing simulation.Procedure. The metamodel from preliminary work based on various FE models, which predicts the load-bearing capacity of a clinched joint influenced by pre-straining, is compared here with experimental data and the accuracy of the metamodel prediction is discussed. For this purpose an experimental procedure was further develop which allows the preforming of metal sheets from which joining specimens can be separated with a certain degree of unidirectional deformation. In the study, the procedure for preparing the joint specimens and the results of the loading tests are presented. Different possible relevant pre-strain combinations are investigated and compared with the simulation results, to validate the FE models and choose suitable metamodel.</jats:p>}},
  author       = {{Bielak, Christian Roman and Böhnke, Max and Bobbert, Mathias and Meschut, Gerson}},
  issn         = {{1662-9795}},
  journal      = {{Key Engineering Materials}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}},
  pages        = {{1516--1526}},
  publisher    = {{Trans Tech Publications, Ltd.}},
  title        = {{{Experimental and Numerical Investigation on Manufacturing-Induced Pre-Strain on the Load-Bearing Capacity of Clinched Joints}}},
  doi          = {{10.4028/p-5d009y}},
  volume       = {{926}},
  year         = {{2022}},
}

@article{29724,
  abstract     = {{<jats:p> In many manufacturing areas, multi-material designs are implemented in which individual components are joined together to form complex structures with numerous joints. For example, in the automotive sector, cast components are used at the junctions of the body and joined with different types of sheet metal and extruded profiles. To be able to join structures consisting of different materials, alternative joining technologies have emerged in recent years. This includes clinching, which allows assembling of two or more thin sheet metal and casting parts by solely cold forming the material. Clinching the brittle and usually less ductile cast aluminium alloys remains a challenge because the brittle character of the cast aluminium alloys can cause cracks during the forming of the clinched joint. In this study, the influence of the heat treatment time of an aluminium casting alloy AlSi9 on the joinability in the clinching process is investigated. Specific heat treatment of the naturally hard AlSi9 leads to a modification of the eutectic microstructure, which can increase ductility. Based on this, it will be examined if specific clinching die geometries can be used, which achieve an optimized geometrical formation of the clinched joint. The load-bearing capacities of the clinched joints are determined and compared by shear tensile and head tensile tests. Furthermore, the joints are examined microscopically to investigate the influence of the heat treatment on the failure behaviour during the load-bearing tests as well as crack initiation within the joining process. </jats:p>}},
  author       = {{Neuser, Moritz and Böhnke, Max and Grydin, Olexandr and Bobbert, Mathias and Schaper, Mirko and Meschut, Gerson}},
  issn         = {{1464-4207}},
  journal      = {{Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications}},
  keywords     = {{Mechanical Engineering, General Materials Science}},
  publisher    = {{SAGE Publications}},
  title        = {{{Influence of heat treatment on the suitability for clinching of the aluminium casting alloy AlSi9}}},
  doi          = {{10.1177/14644207221075838}},
  year         = {{2022}},
}

@article{31828,
  author       = {{Kupfer, Robert and Köhler, Daniel and Römisch, David and Wituschek, Simon and Ewenz, Lars and Kalich, Jan and Weiß, Deborah and Sadeghian, Behdad and Busch, Matthias and Krüger, Jan and Neuser, Moritz and Grydin, Olexandr and Böhnke, Max and Bielak, Christian Roman and Troschitz, Juliane}},
  issn         = {{2666-3309}},
  journal      = {{Journal of Advanced Joining Processes}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, Engineering (miscellaneous), Chemical Engineering (miscellaneous)}},
  publisher    = {{Elsevier BV}},
  title        = {{{Clinching of Aluminum Materials – Methods for the Continuous Characterization of Process, Microstructure and Properties}}},
  doi          = {{10.1016/j.jajp.2022.100108}},
  volume       = {{5}},
  year         = {{2022}},
}

@article{31238,
  author       = {{Kupfer, Robert and Köhler, Daniel and Römisch, David and Wituschek, Simon and Ewenz, Lars and Kalich, Jan and Weiß, Deborah and Sadeghian, Behdad and Busch, Matthias and Krüger, Jan Tobias and Neuser, Moritz and Grydin, Olexandr and Böhnke, Max and Bielak, Christian-Roman and Troschitz, Juliane}},
  issn         = {{2666-3309}},
  journal      = {{Journal of Advanced Joining Processes}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, Engineering (miscellaneous), Chemical Engineering (miscellaneous)}},
  publisher    = {{Elsevier BV}},
  title        = {{{Clinching of Aluminum Materials – Methods for the Continuous Characterization of Process, Microstructure and Properties}}},
  doi          = {{10.1016/j.jajp.2022.100108}},
  year         = {{2022}},
}

@article{34215,
  abstract     = {{Clinching as a mechanical joining technique allows a fast and reliable joining of metal sheets in large-scale production. An efficient design and dimensioning of clinched joints requires a holistic understanding of the material, the joining process and the resulting properties of the joint. In this paper, the process chain for clinching metal sheets is described and experimental techniques are proposed to analyze the process-microstructure-property relationships from the sheet metal to the joined structure. At the example of clinching aluminum EN AW 6014, characterization methods are applied and discussed for the following characteristics: the mechanical properties of the sheet materials, the tribological behavior in the joining system, the joining process and the resulting material structure, the load-bearing behavior of the joint, the damage and degradation as well as the service life and crack growth behavior. The compilation of the characterization methods gives an overview on the advantages and weaknesses of the methods and the multiple interactions of material, process and properties during clinching. In addition, the results of the analyses on EN AW 6014 can be applied for parameterization and validation of simulations.}},
  author       = {{Kupfer, Robert and Köhler, Daniel and Römisch, David and Wituschek, Simon and Ewenz, Lars and Kalich, Jan and Weiß, Deborah and Sadeghian, Behdad and Busch, Matthias and Krüger, Jan Tobias and Neuser, Moritz and Grydin, Olexandr and Böhnke, Max and Bielak, Christian Roman and Troschitz, Juliane}},
  issn         = {{2666-3309}},
  journal      = {{Journal of Advanced Joining Processes}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, Engineering (miscellaneous), Chemical Engineering (miscellaneous)}},
  publisher    = {{Elsevier BV}},
  title        = {{{Clinching of Aluminum Materials – Methods for the Continuous Characterization of Process, Microstructure and Properties}}},
  doi          = {{10.1016/j.jajp.2022.100108}},
  volume       = {{5}},
  year         = {{2022}},
}

@article{33002,
  abstract     = {{<jats:p>Many mechanical material properties show a dependence on the strain rate, e.g. yield stress or elongation at fracture. The quantitative description of the material behavior under dynamic loading is of major importance for the evaluation of crash safety. This is carried out using numerical methods and requires characteristic values for the materials used. For the standardized determination of dynamic characteristic values in sheet metal materials, tensile tests performed according to the guideline from [1]. A particular challenge in dynamic tensile tests is the force measurement during the test. For this purpose, strain gauges are attached on each specimen, wired to the measuring equipment and calibrated. This is a common way to determine a force signal that is as low in vibration and as free of bending moments as possible. The preparation effort for the used strain gauges are enormous. For these reasons, an optical method to determine the force by strain measurement using DIC is presented. The experiments are carried out on a high speed tensile testing system. In combioantion with a 3D DIC high speed system for optical strain measurement. The elastic deformation of the specimen in the dynamometric section is measured using strain gauges and the optical method. The measured signals are then compared to validate the presented method. The investigations are conducted using the dual phase steel material HCT590X and the aluminum material EN AW-6014 T4. Strain rates of up to 240 s-1 are investigated.</jats:p>}},
  author       = {{Böhnke, Max and Unruh, Eduard and Sell, Stanislaw and Bobbert, Mathias and Hein, David and Meschut, Gerson}},
  issn         = {{1662-9795}},
  journal      = {{Key Engineering Materials}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}},
  location     = {{Braga, Portugal}},
  pages        = {{1564--1572}},
  publisher    = {{Trans Tech Publications, Ltd.}},
  title        = {{{Functionality Study of an Optical Measurement Concept for Local Force Signal Determination in High Strain Rate Tensile Tests}}},
  doi          = {{10.4028/p-wpuzyw}},
  volume       = {{926}},
  year         = {{2022}},
}

@inbook{33003,
  author       = {{Böhnke, Max and Bielak, Christian Roman and Bobbert, Mathias and Meschut, Gerson}},
  booktitle    = {{The Minerals, Metals &amp; Materials Series}},
  isbn         = {{9783031062117}},
  issn         = {{2367-1181}},
  location     = {{Toronto, Kanada}},
  publisher    = {{Springer International Publishing}},
  title        = {{{Development of a Modified Punch Test for Investigating the Failure Behavior in Sheet Metal Materials}}},
  doi          = {{10.1007/978-3-031-06212-4_52}},
  year         = {{2022}},
}