Topology-optimized design for additively manufactured composites

Composites and especially fiber-reinforced plastics (FRP) with continuous reinforcement ideally feature as lightweight materials. Developments in the field of additive manufacturing processes, such as tape-laying technologies, tailored fiber placement or 3D printing, are opening up completely new possibilities in the design of FRP components.

The interdisciplinary junior research group "TopComposite" at Leibniz-Institut für Verbundwerkstoffe (IVW) is developing wet fiber placement as an additive manufacturing process for the production of FRP components. It allows direct deposition of fiber bundles, which are impregnated in situ with a thermosetting resin. A corresponding new design method to be developed benefits from the lightweight potential of the new process, and also takes the anisotropic material properties as well as any manufacturing restrictions into account. Topology optimization is the core element of this new design method. The mathematical method removes unnecessary material from the part in the defined design space and maximizes its stiffness. In addition, the fiber orientation within the part is simultaneously optimized by a topology optimization algorithm, which has already been developed at IVW. The algorithm is extended to the effect, that even manufacturing restrictions – such as minimum placement width and avoiding cavities transverse to the placement plane – can be included.  Another algorithm has been evolved in order to derive the placement paths – which are essential for additive manufacturing – according to the gained optimization results. The proposed design methodology (Fig. 1) does not only allow a resource-efficient and lightweight component design, but can also help to accelerate the product development process due to the high degree of automation.

Current investigations within the project take any defects occurring during fiber depositing in the component design into account and also evaluate a design methodology for intersections and force introduction elements for additively manufactured FRP components.

The project "TopComposite – Topology-optimized and resource-efficient composites for mobility and transport" is funded by the Federal Ministry of Education and Research (funding reference 03XP0259).

Project Advisory Board:

• ACE Advanced Composite Engineering GmbH
• AVK – Industrievereinigung Verstärkte Kunststoffe e.V.
• BMW AG
• Centre for Advanced Composite Materials (CACM), The University of Auckland, New Zealand
• Hexion Germany GmbH
• InnoMat GmbH
• Leibniz-Institut für Verbundwerkstoffe GmbH

Contact:
Dipl.-Ing. Maximilian Eckrich
Junior Research Group TopComposite
Leibniz-Institut für Verbundwerkstoffe GmbH
Erwin-Schrödinger-Straße 58
67663 Kaiserslautern
Phone: +49 631 2017-228
E-Mail: maximilian.eckrich@ivw.uni-kl.de