Home Publications Research Data Research Grants Equipment Inventions & Patents Awards Additional Research Activities Faculties & Institutions Research Areas

Mechanical joining without auxiliary elements (TRR 285 C01)

Third Party Funds Group - Sub project

Acronym: TRR 285 C01

Start date : 01.07.2019

End date : 30.06.2027

Website: https://trr285.uni-paderborn.de/

---

• Overview

   

• Publications

  (31)

• External partners

  (2)

Overall project details

Overall project

Project details

Short description

Modern engineering structures increasingly rely on hybrid material systems in which different materials are combined according to their specific properties. The resulting increase in material diversity places high demands on adaptable and resource-efficient joining technologies. Pin joining offers a novel approach for creating robust joints between dissimilar materials without the need for additional auxiliary joining elements.

In pin joining, metallic pins are locally formed directly from the base material by forward extrusion. These integral structural elements are subsequently used to join a counterpart material – within the scope of this project, either aluminium or fibre-reinforced polymers (FRP). Different joining strategies can be applied: the formed pins may be pressed directly into the joining partner or inserted through pre-drilled holes and subsequently caulked. In both cases, a combined force- and form-fit joint is created, whose mechanical properties are strongly influenced by the pin geometry, local material hardening, and the interaction between pin and joining partner.

The first phase of the project focused on the fundamental investigation of single-pin joints. The objective was to systematically analyse the underlying mechanisms and develop a comprehensive understanding of the relevant process–structure relationships. To this end, manufacturing processes, achievable pin geometries, local material modifications, and load-bearing capacities as well as failure mechanisms were investigated experimentally. In addition, different process strategies were evaluated with regard to their influence on joint quality and mechanical and geometrical properties.

The currently ongoing second phase transfers these findings to more complex multi-pin joints. Particular emphasis is placed on the interactions between neighbouring pins and their influence on load transfer, stress distribution, and the overall load-bearing capacity of the joint. The aim is to establish a profound understanding of pin interaction effects in order to enable the load- and material-specific design of multi-pin joints and to predict and tailor their mechanical behaviour.

Pin joining therefore offers considerable potential as a resource-efficient, adaptable, and auxiliary-element-free alternative to conventional joining technologies. In particular, the process opens up new opportunities for the realisation of high-performance and sustainable hybrid lightweight structures

Scientific Abstract

Modern engineering structures increasingly rely on hybrid material systems in which different materials are combined according to their specific properties. The resulting increase in material diversity places high demands on adaptable and resource-efficient joining technologies. Pin joining offers a novel approach for creating robust joints between dissimilar materials without the need for additional auxiliary joining elements.

In pin joining, metallic pins are locally formed directly from the base material by forward extrusion. These integral structural elements are subsequently used to join a counterpart material – within the scope of this project, either aluminium or fibre-reinforced polymers (FRP). Different joining strategies can be applied: the formed pins may be pressed directly into the joining partner or inserted through pre-drilled holes and subsequently caulked. In both cases, a combined force- and form-fit joint is created, whose mechanical properties are strongly influenced by the pin geometry, local material hardening, and the interaction between pin and joining partner.

The first phase of the project focused on the fundamental investigation of single-pin joints. The objective was to systematically analyse the underlying mechanisms and develop a comprehensive understanding of the relevant process–structure relationships. To this end, manufacturing processes, achievable pin geometries, local material modifications, and load-bearing capacities as well as failure mechanisms were investigated experimentally. In addition, different process strategies were evaluated with regard to their influence on joint quality and mechanical and geometrical properties.

The currently ongoing second phase transfers these findings to more complex multi-pin joints. Particular emphasis is placed on the interactions between neighbouring pins and their influence on load transfer, stress distribution, and the overall load-bearing capacity of the joint. The aim is to establish a profound understanding of pin interaction effects in order to enable the load- and material-specific design of multi-pin joints and to predict and tailor their mechanical behaviour.

Pin joining therefore offers considerable potential as a resource-efficient, adaptable, and auxiliary-element-free alternative to conventional joining technologies. In particular, the process opens up new opportunities for the realisation of high-performance and sustainable hybrid lightweight structures.

Involved:

Contributing FAU Organisations:

Funding Source

Research Areas