@inproceedings{59483,
  abstract     = {{<jats:p>Abstract. The assessment of mechanically joined connections, such as clinched connections, is usually conducted destructively. Applicable non-destructive testing methods like computed tomography are time-consuming and costly, or, like electrical resistance measurement, provide only a limited amount of information. A fast, non-destructive evaluation of the joints condition shall be made possible by using transient dynamic analysis (TDA). It is based on the introduction of sound waves and the evaluation of the response behavior after passing through the structure. This study focuses the application of TDA to clinched shear connections to evaluate the performance of the tactile measuring setup. Twenty-one series were investigated, covering variations in joining task, manufacturing and defect. The evaluation was carried out using machine learning to determine for which series characteristic signals may be detected. It was shown that a classification of the investigated specimens is possible, whereby the classification accuracy depends on the examined variation. Furthermore, the accuracy was evaluated as a function of frequency and results were concluded to identify the limits of the used measuring setup.</jats:p>}},
  author       = {{Reschke, Gregor and Brosius, Alexander}},
  booktitle    = {{Materials Research Proceedings}},
  issn         = {{2474-395X}},
  keywords     = {{Joining, Machine Learning, Transient Dynamic Analysis}},
  location     = {{Paderborn}},
  pages        = {{293--300}},
  publisher    = {{Materials Research Forum LLC}},
  title        = {{{Transient dynamic analysis: Performance evaluation of tactile measurement}}},
  doi          = {{10.21741/9781644903551-36}},
  volume       = {{52}},
  year         = {{2025}},
}

@article{58348,
  abstract     = {{<jats:p> Clinching is a mechanical joining technology, in which a mainly form-fit joint is created by means of local cold forming. To characterize the load-bearing behavior of such joints, they are typically analyzed destructively, for example by tensile-shear tests in combination with metallographic sections. However, both the initiation and progress of failure can only be described to a limited extent by this method. Furthermore, these tests allow only limited conclusions about clinch points under in-service loading. More purposefully, clinch points can be analyzed nondestructively by combining in-situ computed tomography (CT) and transient dynamic analysis (TDA). The TDA continuously measures the dynamic behavior of the specimen and indicates failure events like crack initiation, which then can be evaluated thoroughly by stopping the test and performing a CT scan. To qualify the TDA for this task, it is necessary to link the observed damage behavior with specific dynamic characteristics. In this work, the complementation of in-situ CT and TDA is investigated by testing a clinched single-lap tensile-shear specimen made of aluminum. The testing procedure is stepwise: at certain displacement levels, the specimen is investigated by in-situ CT and TDA. While the in-situ CT provides the location, extent, and development of the failure phenomena, the TDA uses this information to evaluate the dynamic signal and detect relevant frequency ranges, which indicate damage events. The results demonstrate, that failure initiation and progression can be analyzed efficiently by combining both measuring systems. The TDA reliably detects relevant signal changes in the monitored frequency band. By means of in-situ computed tomography, the corresponding failure phenomena can be described in detail, enhancing the understanding of the load-bearing and deformation behavior of clinch points. The concatenation of characteristic signal changes and observed failure phenomena can henceforth be transferred to analyze complex structures during operation nondestructively by TDA. </jats:p>}},
  author       = {{Reschke, Gregor and Köhler, Daniel and Kupfer, Robert and Troschitz, Juliane and Gude, Maik and Brosius, Alexander}},
  issn         = {{0954-4089}},
  journal      = {{Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering}},
  keywords     = {{Clinching, Non-destructive testing, Transient Dynamic Analysis}},
  publisher    = {{SAGE Publications}},
  title        = {{{In-situ computed tomography and transient dynamic analysis – failure analysis of a single-lap tensile-shear test with clinch points}}},
  doi          = {{10.1177/09544089241251646}},
  year         = {{2024}},
}