TransHybrid – Hybrid Joining Technologies for Lightweight Design in Transport Applications

Extending a holistic approach for lightweight design to diverse transport applications by customized material combinations between FRP and metal.

Project Partners
Audi AG, Bombardier Transportation GmbH, DB Waggonbau Niesky GmbH, EADS Deutschland GmbH, EAST-4D Carbon Technology GmbH, Eurocopter Deutschland GmbH, Fraunhofer-Institut für Chemische Technologie (ICT), Fraunhofer Institut für Fertigungstechnik und angewandte Materialforschung (IFAM), Hoelzel Stanz- und Feinwerktechnik GmbH & Co. KG, INVENT GmbH, LCS Life Cycle Simulation GmbH, Leibniz Universität Hannover, Rolls-Royce Deutschland Ltd. & Co. KG, RUAG Aero Structures GmbH, Technische Universität Dresden, Volkswagen AG

Duration
01.11.2012 – 31.10.2015

Funding Authority
German Federal Ministry of Education and Research

Motivation
Composite construction is already state of the art in lightweight structures for transport applications. It contributes significantly to weight reduction as well as to conservation of resources and cost reduction. Goal of the project TransHybrid was to extend a holistic approach for lightweight design to diverse transport applications by customized material combinations between fiber reinforced plastics (FRP) and metal (e.g. Ti/CFRF, Al/CFRP, St/CFRP, metal/GFRP). Within the project, joining technologies particularly for multi-material systems had to be examined, optimized and developed. With these new technologies, cost-neutral weight reductions between 20 and 30 % should be achieved by the implied conservation of resources. Due to this weight reduction, fuel savings in the whole transportation sector such as road, rail or air traffic will be achieved and the innovative strength as well as the competitive position of German vehicle manufacturers and suppliers will be enhanced. The economic benefit of the project was provided through participation of all industry sectors along the process chain.

Method
Within the subproject of TUM-LCC, the mechanical response of CFRP/aluminium joints was investigated by simulation and experiments. The results were transferred into a finite element modelling approach. This approached comprised the development of a new cohesive element that combined the material behavior in the laminate and the adhesive layer. Through this, an effective modelling of the joint should be reached especially in macroscopic models of e.g. an overall vehicle body. A seperate consideration of potential delamination zones in the CFRP laminate would have been too computationally costly. The goal was to integrate the new cohesive element into commercial software in order that it is available for project partners in the automotive, aviation and rail sector.

Publications
Neumayer, J.; Körber, H.; Hinterhölzl, R.: An explicit cohesive element combining cohesive failure of the adhesive and delamination failure in composite bonded joints. Composite Structures 146, 2016, 75-83
Neumayer, J.; Kuhn, P.; Körber, H.; Hinterhölzl, R.: Experimental Determination of the Tensile and Shear Behaviour of Adhesives Under Impact Loading. The Journal of Adhesion, 2015

Acknowledgement
The chair thankfully acknowledges the funding of the project “Hybrid-Fügetechnologien für Leichtbauweisen bei Transportanwendungen – TransHybrid” provided by the German Federal Ministry of Education and Research on the topic „Multimaterialsysteme - Zukünftige Leichtbauweisen für ressourcensparende Mobilität" within the programme scheme "Werkstoffinnovationen für Industrie und Gesellschaft - WING" (funding code: 13N11993).