[HyTo3D] Process for hybrid manufacturing and topology optimization of overmolded 3D-winding structures for lightweight, cost-sensitive structural components

• Applicants: Professor Dr.-Ing. Ingolf Mueller; Dr.-Ing. Sebastian Schmeer
• Subject Area: Lightweight Construction, Textile Technology
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 550248900

In the HyTo3D research project, a novel concept for efficient and load-related structures will be developed from a hybridization of short-fiber reinforced thermoplastic with local, thermoset continuous-fiber reinforcement. Interactively, a special method for the design of these structures will be developed based on an extended approach for topology optimization, enabling structural components with the highest strength and stiffness while using the least mass, as well as being cost-effective and suitable for large-scale production. An automated, robot-based 3D filament winding process for structures must be developed respectively significantly expanded for the production of the continuous fiber reinforcements to be able to manufacture complex, load-path-compatible structures with a variable number of filaments and a high lightweight factor. A subsequently overmolding process with short-fiber-reinforced plastics is intended to increase the compressive stiffness/strength and surface quality and to create functional surfaces. Thermoset continuous fiber reinforced structures are overmolded with thermoplastic material in order to overcome the process and geometry limitations that exist in the purely thermoplastic process. The material-related high stiffnesses of the thermoset reinforcements enables the production of finer geometries that deform significantly less than thermoplastic inserts during the high temperatures of the injection molding process. In addition, the properties of the final component are less influenced by temperature and humidity when using thermoset reinforcements compared to thermoplastics reinforcements. The possibilities offered by the material combination and the manufacturing process are described in numerical simulations and integrated in a topology optimization adapted to the manufacturing process. The optimization algorithm should consider the anisotropy of the reinforcing material (continuous fiber- reinforced thermoset) and the stiffness of the base material (short-fiber-reinforced thermoplastic), include the interface strength between the materials and also be able to decide where material can be omitted completely. In this way, the potential of the material combination should be fully utilized. In order to develop and improve the manufacturing process and the topology optimization, various demonstrators will be manufactured during the project (2D- and 3D-demonstrators). As the complexity of the test specimens and demonstrators increase, the manufacturing process and the topology optimization will be validated and continuously developed during the project. Demonstrators reinforced based on isotropic, single-phase topology optimizers provide the reference for evaluating the developments.

• DFG Programme: Research Grants