Comparison of ex- and in-situ investigations of clinched single-lap shear specimens

Comparison of ex- and in-situ investigations of clinched single-lap shear specimens

Daniel Köhler, Aiting Yu, Robert Kupfer, Juliane Troschitz, Maik Gude

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Abstract. Force-displacement measurements and macrosections are commonly used methods to validate numerical models of clinching processes. However, these ex-situ methods often lead to springback of elastic deformations and crack-closing after unloading. In contrast, the in-situ computed tomography (CT) can provide three-dimensional images of the clinching point under loading conditions. So far, the quantity of elastic springback that causes measuring deviations between in- and ex-situ measurements is not determined. In this paper, a method is described to quantitatively compare the results of in-situ CT, ex-situ CT and CT scans of cut specimens, which are prepared for macrosectioning, among each other. The method is applied to a single-lap shear test of two clinched aluminum sheets. Here, the test is conducted to specific process steps, then the specimen is CT scanned in-situ (during loading) and ex-situ (after unloading). Subsequently, the specimens are cut for macrosectioning and CT scanned. Finally, the outer contours and the interfaces of cross section images are determined by digital image analysis and the deviations over the clinching point between ex- and in-situ methods are calculated.

X-Ray, In-Process Measurement, Clinching

Published online 3/17/2023, 8 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Daniel Köhler, Aiting Yu, Robert Kupfer, Juliane Troschitz, Maik Gude, Comparison of ex- and in-situ investigations of clinched single-lap shear specimens, Materials Research Proceedings, Vol. 25, pp 155-162, 2023


The article was published as article 20 of the book Sheet Metal 2023

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

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