Investigation on pin caulking as a versatile joining process

Investigation on pin caulking as a versatile joining process

David Römisch, Marion Merklein

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Abstract. Lightweight design is increasingly used to combine the specific advantages of various dissimilar materials into multi-material systems. The aim is to make production more resource-efficient and reduce emissions. However, one challenge in the adaptation of multi-material systems is the lack of versatile joining technologies capable of joining these materials. Joining with cold formed pins is a two-step process with potential in joining metal to metal and metal to fibre-reinforced plastics (FRP). These pins can be joined using two joining strategies, direct pin pressing into an unperforated joining partner and caulking of pins, which are inserted through a pre-punched joining partner. For pin pressing, several studies have already been carried out regarding joinability of steel and aluminium, but caulking offers advantages such as a reduced joining force and the fact that the pin can transmit force over the entire sheet thickness of the joining partner, which can lead to increased strength under axial load. Therefore, the caulking of pins extruded from dual-phase steel with a 6000 aluminium alloy is investigated. The focus is on a fundamental investigation of the joining process and the joint formation when caulking pins of varying heights with sheets of different thicknesses. Subsequently, a process window is derived from these findings.

Joining, Metal, Pin Caulking

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: David Römisch, Marion Merklein, Investigation on pin caulking as a versatile joining process, Materials Research Proceedings, Vol. 25, pp 109-116, 2023


The article was published as article 14 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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