The latest updates about adhesive bonding at Fraunhofer IFAM can also be found on our LinkedIn page.
Marvin Kaufmann wins award "Best Oral Presentation" at AB2023
Marvin Kaufmann of Fraunhofer IFAM received the award "Best Oral Presentation" from the "Scientific Committee" of the "7th International Conference on Structural Adhesive Bonding AB2023" for his presentation "How adhesives flow during joining". He received a certificate and a book prize from Lucas F. M. da Silva, the chairman and organizer of the conference. The conference is held every two years in Porto.
The topic "How adhesives flow during joining" represents a combination of great experimental work and modeling, involving process development and systematic analysis to address a significant problem in adhesive technology. His work is very innovative because the new method clearly shows how adhesives flow during joining. This novel and more comprehensive approach will certainly save costs, but more importantly will improve sustainability as less "trial & error" is required to determine the ideal application pattern, and as overfilling is completely avoided, which in turn reduces waste and cleaning.
Presentation "Simulation of adhesive bonding manufacturing technology"
Our colleague Holger Fricke opened this year's conference "Adhesive Bonding - AB2023" in Porto with the presentation "Simulation of adhesive bonding manufacturing technology". The importance of adhesive bonding manufacturing technology for the quality of industrial products is increasingly taken into account. A complete testing of bonded joints is technically not possible, therefore the quality of each produced bonded joint still depends on the correct execution of the manufacturing process. For more than 20 years, Fraunhofer IFAM has been developing specific simulations to understand in detail the manufacturing steps of dosing, applying, joining, fixing, hybrid joining, and curing, thereby minimizing sources of error. In his overview presentation, he briefly outlined the thematically related presentations by Marvin Kaufmann, Till Vallée, Jonas Wirries, Moritz Huf, Koichi Yokozeki, Michael Müller and Florian Flaig.
Presentation "Adhesive bonding works - even with few joining points"
Hybrid joining in automotive body-in-white combines adhesive bonding with mechanical joining points or spot welds. It combines the high crash energy absorption capacity and stiffness of bonded joints with the fast process speed and peel strength of mechanical/thermal joining. The hybrid joining points are usually placed at a constant spacing to hold the bond in place until curing of the adhesive. However, the mechanical joining points and welding spots interfere with the formation of an optimally dimensioned and uniform adhesive layer. As a result, they significantly reduce the load-bearing capacity of the adhesive.
In the presentation "Adhesive Bonding works - even with few joining points" at the "Joining in Car Body Engineering" conference of the "Automotive Circle", Moritz Huf from BMW and Holger Fricke from Fraunhofer IFAM addressed the question of what spacing should ideally be maintained for a given hybrid joint? Using the results of fluid structure simulations, they were able to significantly reduce the number of joining points while increasing the quality of the bonded joints. The presenters showed examples in which they were able to increase the joining point distance from 50mm to over 150mm.
Understanding and optimizing adhesive bonding production
In adhesive bonding, the manufacturing process is a key for improving the quality of the final product. Fraunhofer IFAM in Bremen has been researching the flow behavior of adhesives for two decades to understand industrial dispensing, application, and squeezing with the aim to improve adhesive manufacturing. A recent publication investigates the flow during the squeezing of an adhesive bead during the joining process. The industrial squeezing of the bead is modeled experimentally by "squeeze flow tests" and characterized with high accuracy. Research is conducted into how the surface of an adherend affects adhesive flow. The article "Do surface pretreatments for adhesives influence the squeeze flow?" can now be downloaded here.