Clinching with divided punch to prevent critical neck thicknesses

Clinching with divided punch to prevent critical neck thicknesses

FALK Tobias, KROPP Thomas, DROSSEL Welf-Guntram

Abstract. Clinching thin sheet metal into a thicker part can result in low neck thicknesses or even neck cracks. How these critical low values for neck thickness can be counteracted is described in this paper, using a two-part punch, which is devided in an inner and outer unit. At the beginning, both move parallel in the direction of the die until the outer punch stops at a defined position and only the inner one moves further down and forms the clinch point, with its characteristic contour and the geometric values of interlock and neck thickness. Due to the large punch diameter at the beginning of the process, more material initially flows into the neck area than in conventional clinching, so that a greater neck thickness can be achieved. Numerical simulation was used to create the concept and verify it experimentally. The greater neck thickness has a positive effect on the shear tensile strength and can also be transferred to the typical joining direction for clinching (thick into thin material).

Keywords
Clinching, Divided Punch, Critical Neck Thickness, Crack Prevention

Published online 4/19/2023, 8 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: FALK Tobias, KROPP Thomas, DROSSEL Welf-Guntram, Clinching with divided punch to prevent critical neck thicknesses, Materials Research Proceedings, Vol. 28, pp 1059-1066, 2023

DOI: https://doi.org/10.21741/9781644902479-116

The article was published as article 116 of the book Material Forming

Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. 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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