@article{66457,
  abstract     = {{<jats:title>Abstract</jats:title>
                  <jats:p>The service life of fatigue-loaded components that already contain manufacturing‑induced microcracks is primarily governed by the direction and the rate of fatigue-crack growth. When multiple loading components (e.g., tension, compression, shear) act simultaneously but not in temporal synchrony, out‑of‑phase mixed‑mode conditions occur. Such loadings are typical for automotive chassis parts and mechanically joined sheet‑metal assemblies. For optimized design of structural components, the crack kinking angle that occurs under mixed‑mode loading must be predicted as accurately as possible. At present, however, this is still challenging for out‑of‑phase loading conditions. To investigate the associated crack kinking behavior, a novel Compact‑Tension‑Shear‑Mini (CTSM) specimen was developed, enabling controlled generation of plane out-of-phase mixed-mode loading states. Experiments were performed under various combinations of cyclic and static mode I and mode II load components and compared with the analytical predictions of the Out-of-Phase Mixed-Mode (OMM) concept. The measured crack kinking angles showed very good agreement with the predicted values, with mean deviations of only a few degrees, demonstrating the validity and reproducibility of the approach. These findings confirm the applicability of the OMM concept for describing fatigue‑crack propagation under non‑proportional mixed‑mode loading and provide a basis for fatigue‑life assessment of clinched joints and other cyclic multi-axially loaded components.</jats:p>}},
  author       = {{Krome, Sven and Kullmer, Gunter and Weiß, Deborah and Duffe, Tobias and Ostwald, Richard}},
  issn         = {{2731-6564}},
  journal      = {{Discover Mechanical Engineering}},
  number       = {{1}},
  publisher    = {{Springer Science and Business Media LLC}},
  title        = {{{Experimental determination of kinking angles with out-of-phase mixed-mode loading by means of a novel specimen geometry}}},
  doi          = {{10.1007/s44245-026-00236-5}},
  volume       = {{5}},
  year         = {{2026}},
}

@article{66673,
  abstract     = {{<jats:p>Investigating crack growth in sheet metal originating from clinched joints is a major part of predicting the service life of mechanically joined structures. Clinching allows different materials to be joined together. A key task in this context is to perform crack growth simulations in the vicinity of clinched joints considering different load and environmental conditions. This requires formulaic descriptions of the fatigue crack growth rate curves for the materials used. For this purpose, fatigue crack growth rate curves for different R-ratios and temperatures are determined experimentally. Generally, these fatigue crack growth rate curves can be described very well using a novel two-part exponential approach for the formulaic description of fatigue crack growth rate curves developed at Applied Mechanics of Paderborn University (FAM). In this case, three parameters are sufficient to describe the fatigue crack growth rate curves. For the material HCT590X, which is frequently used in clinched joints, it is shown as an example how the parameters vary with the R-ratio and the temperature. In addition, at high crack growth rates, a significant rise in the fatigue crack growth rate curve sometimes occurs at both low and high temperatures. To account for this feature, the two-part exponential approach can be expanded to include a third part.</jats:p>}},
  author       = {{Kullmer, Gunter and Krome, Sven and Weiß, Deborah and Schramm, Britta and Ostwald, Richard}},
  issn         = {{2075-4701}},
  journal      = {{Metals}},
  number       = {{8}},
  publisher    = {{MDPI AG}},
  title        = {{{Influence of the R-Ratio and the Temperature on the Coefficients of a Novel Exponential Approach for the Formulaic Description of Fatigue Crack Growth Rate Curves}}},
  doi          = {{10.3390/met16080835}},
  volume       = {{16}},
  year         = {{2026}},
}

@article{63662,
  abstract     = {{The accurate prediction of crack initiation and propagation is essential for assessing the structural integrity of mechanically joined components and other complex assemblies. To overcome the limitations of existing finite element tools, a modular Python framework has been developed to automate three-dimensional crack growth simulations. The program combines geometric reconstruction, adaptive remeshing, and the numerical evaluation of fracture mechanics parameters within a single, fully automated workflow. The framework builds on open-source components and remains solver-independent, enabling straightforward integration with commercial or research finite element codes. A dedicated sequence of modules performs all required steps, from mesh separation and crack insertion to local submodeling, stress and displacement mapping, and iterative crack-front update, without manual interaction. The methodology was verified using a mini-compact tension (Mini-CT) specimen as a benchmark case. The numerical results demonstrate the accurate reproduction of stress intensity factors and energy release rates while achieving high computational efficiency through localized refinement. The developed approach provides a robust basis for crack growth simulations of geometrically complex or residual stress-affected structures. Its high degree of automation and flexibility makes it particularly suited for analyzing cracks in clinched and riveted joints, supporting the predictive design and durability assessment of joined lightweight structures.}},
  author       = {{Krome, Sven and Duffe, Tobias and Kullmer, Gunter and Schramm, Britta and Ostwald, Richard}},
  issn         = {{2076-3417}},
  journal      = {{Applied Sciences}},
  number       = {{1}},
  publisher    = {{MDPI AG}},
  title        = {{{Validation and Verification of Novel Three-Dimensional Crack Growth Simulation Software GmshCrack3D}}},
  doi          = {{10.3390/app16010384}},
  volume       = {{16}},
  year         = {{2025}},
}

@article{51737,
  author       = {{Kullmer, Gunter and Weiß, Deborah and Schramm, Britta}},
  issn         = {{0013-7944}},
  journal      = {{Engineering Fracture Mechanics}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}},
  publisher    = {{Elsevier BV}},
  title        = {{{An alternative and robust formulation of the fatigue crack growth rate curve for long cracks}}},
  doi          = {{10.1016/j.engfracmech.2023.109826}},
  volume       = {{296}},
  year         = {{2024}},
}

@inproceedings{53394,
  author       = {{Kullmer, Gunter and Weiß, Deborah and Schramm, Britta}},
  location     = {{Kassel}},
  publisher    = {{Deutscher Verband für Materialforschung und –prüfung e.V.}},
  title        = {{{Weiterentwicklung des Exponentialansatzes zur Beschreibung von Rissfortschrittskurven}}},
  doi          = {{10.48447/BR-2024-369}},
  year         = {{2024}},
}

@inproceedings{51739,
  author       = {{Weiß, Deborah and Duffe, Tobias and Buczek, Moritz and Kullmer, Gunter and Schramm, Britta}},
  location     = {{Berlin}},
  publisher    = {{Deutscher Verband für Materialforschung und -prüfung e.V.}},
  title        = {{{Bruchmechanische Untersuchung des Dualphasenstahls HCT590X unter Temperatureinfluss}}},
  doi          = {{10.48447/WP-2023-244}},
  year         = {{2023}},
}

@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}},
}

@inproceedings{35271,
  author       = {{Weiß, Deborah and Schramm, Britta}},
  booktitle    = {{Procedia Structural Integrity}},
  issn         = {{2452-3216}},
  keywords     = {{General Engineering, Energy Engineering and Power Technology}},
  location     = {{Madeira}},
  pages        = {{879--885}},
  publisher    = {{Elsevier BV}},
  title        = {{{Fracture mechanical investigation of preformed metal sheets using a novel CC-specimen}}},
  doi          = {{10.1016/j.prostr.2022.12.111}},
  volume       = {{42}},
  year         = {{2022}},
}

@article{34224,
  abstract     = {{Crack growth in structures depends on the cyclic loads applied on it, such as mechanical, thermal and contact, as well as residual stresses, etc. To provide an accurate simulation of crack growth in structures, it is of high importance to integrate all kinds of loading situations in the simulations. Adapcrack3D is a simulation program that can accurately predict the propagation of cracks in real structures. However, until now, this three-dimensional program has only considered mechanical loads and static thermal loads. Therefore, the features of Adapcrack3D have been extended by including contact loading in crack growth simulations. The numerical simulation of crack propagation with Adapcrack3D is generally carried out using FE models of structures provided by the user. For simulating models with contact loading situations, Adapcrack3D has been updated to work with FE models containing multiple parts and necessary features such as coupling and surface interactions. Because Adapcrack3D uses the submodel technique for fracture mechanical evaluations, the architecture of the submodel is also modified to simulate models with contact definitions between the crack surfaces. This paper discusses the newly implemented attribute of the program with the help of illustrative examples. The results confirm that the contact simulation in Adapcrack3D is a major step in improving the functionality of the program.}},
  author       = {{Joy, Tintu David and Weiß, Deborah and Schramm, Britta and Kullmer, Gunter}},
  issn         = {{2076-3417}},
  journal      = {{Applied Sciences}},
  keywords     = {{Fluid Flow and Transfer Processes, Computer Science Applications, Process Chemistry and Technology, General Engineering, Instrumentation, General Materials Science}},
  number       = {{15}},
  publisher    = {{MDPI AG}},
  title        = {{{Further Development of 3D Crack Growth Simulation Program to Include Contact Loading Situations}}},
  doi          = {{10.3390/app12157557}},
  volume       = {{12}},
  year         = {{2022}},
}

@inproceedings{30726,
  author       = {{Weiß, Deborah and Schramm, Britta and Kullmer, Gunter}},
  booktitle    = {{Procedia Structural Integrity}},
  issn         = {{2452-3216}},
  keywords     = {{General Engineering, Energy Engineering and Power Technology}},
  location     = {{online}},
  pages        = {{139--147}},
  publisher    = {{Elsevier BV}},
  title        = {{{Influence of plane mixed-mode loading on the kinking angle of clinchable metal sheets}}},
  doi          = {{10.1016/j.prostr.2022.03.082}},
  volume       = {{39}},
  year         = {{2022}},
}

@article{34246,
  author       = {{Kullmer, Gunter and Weiß, Deborah and Schramm, Britta}},
  issn         = {{0013-7944}},
  journal      = {{Engineering Fracture Mechanics}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}},
  publisher    = {{Elsevier BV}},
  title        = {{{Development of a method for the separate measurement of the growth of internal crack tips by means of the potential drop method}}},
  doi          = {{10.1016/j.engfracmech.2022.108899}},
  year         = {{2022}},
}

@article{34403,
  abstract     = {{For a reliable, strength-compliant and fracture-resistant design of components and technical structures and for the prevention of damage cases, both the criteria of strength calculation and fracture mechanics are essential. In contrast to strength calculation the fracture mechanics assumes the existence of cracks which might further propagate due to the operational load. First, the present paper illustrates the general procedure of a fracture mechanical evaluation of fatigue cracks in order to assess practical damage cases. Fracture mechanical fundamentals which are essential for the calculation of the stress intensity factors <jats:italic>K</jats:italic>
                  <jats:sub>I</jats:sub> and the experimental determination of fracture mechanical material parameters (e.g. threshold Δ<jats:italic>K</jats:italic>
                  <jats:sub>I,th</jats:sub> against fatigue crack growth, crack growth rate curve) are explained in detail. The subsequent fracture mechanical evaluation on the basis of the local stress situation at the crack tip and the fracture mechanical material data is executed for different materials and selected crack problems. Hereby, the main focus is on the material HCT590X as it is the essential material being investigated by TRR285.</jats:p>}},
  author       = {{Schramm, Britta and Weiß, Deborah}},
  issn         = {{0025-5300}},
  journal      = {{Materials Testing}},
  keywords     = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}},
  number       = {{10}},
  pages        = {{1437--1449}},
  publisher    = {{Walter de Gruyter GmbH}},
  title        = {{{Fracture mechanical evaluation of the material HCT590X}}},
  doi          = {{10.1515/mt-2022-0191}},
  volume       = {{64}},
  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{34070,
  author       = {{Schramm, Britta and Harzheim, Sven and Weiß, Deborah and Joy, Tintu David and Hofmann, Martin and Mergheim, Julia and Wallmersperger, Thomas}},
  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 III: Operational Phase}}},
  doi          = {{10.1016/j.jajp.2022.100135}},
  year         = {{2022}},
}

@article{30680,
  author       = {{Weiß, D. and Schramm, B. and Kullmer, G.}},
  journal      = {{Key Engineering Materials}},
  pages        = {{127--132}},
  title        = {{{Numerical and Experimental Fracture Mechanical Investigations of Clinchable Sheet Metals Made of HCT590X}}},
  doi          = {{10.4028/www.scientific.net/kem.883.127}},
  volume       = {{883}},
  year         = {{2021}},
}

@article{30699,
  author       = {{Weiß, D. and Schramm, B. and Kullmer, G.}},
  journal      = {{Production Engineering}},
  title        = {{{Holistic investigation chain for the experimental determination of fracture mechanical material parameters with special specimens}}},
  doi          = {{10.1007/s11740-021-01096-6}},
  year         = {{2021}},
}

@inproceedings{34472,
  author       = {{Kullmer, Gunter and Weiß, Deborah and Schramm, Britta}},
  location     = {{Bremen}},
  pages        = {{107--116}},
  title        = {{{Entwicklung einer Methode zur differenzierten Messung des Wachstums der Rissenden von Innenrissen mit der Elektropotentialmethode}}},
  doi          = {{10.48447/BR-2021-013}},
  volume       = {{DVM-Bericht 253}},
  year         = {{2021}},
}

@inproceedings{24006,
  author       = {{Weiß, Deborah and Schramm, Britta and Neuser, Moritz and Grydin, Olexandr and Kullmer, Gunter}},
  location     = {{Bremen}},
  pages        = {{231--240}},
  title        = {{{Experimentelle bruchmechanische Untersuchung eines clinchgeeigneten Bleches aus HCT590X mithilfe einer neuen Probengeometrie}}},
  doi          = {{10.48447/BR-2021-025}},
  volume       = {{DVM-Bericht 253}},
  year         = {{2021}},
}

@inproceedings{23980,
  author       = {{Weiß, Deborah and Schramm, Britta and Kullmer, Gunter}},
  location     = {{online}},
  pages        = {{2335--2341}},
  publisher    = {{Elsevier}},
  title        = {{{Development of a special specimen geometry for the experimental determination of fracture mechanical parameters of clinchable metal sheets}}},
  doi          = {{10.1016/j.prostr.2020.11.081}},
  volume       = {{28}},
  year         = {{2020}},
}