Prozesskette zur Herstellung von hybriden Faser-Metall-Preforms - Modellbildung und Optimierung des Binderauftrags und der Drapierung für stabförmige Bauteile

Hybrid fibre composite-metal rods are suitable for mechanically highly stressed applications due to their high lightweight potential. In terms of multi-material design, the load introduction is made of metal, while the load transmission area is made of composite material. In the state of the art, the rotational moulding process has been qualified as a highly efficient and flexible manufacturing process for intrinsic hybridization for the production of such components. The rotational moulding process can be used to produce highly durable joints between metal and composites. However, a hybrid preform is required before the actual infiltration. This consists of a stabilized, near-net-shape draped fibre preform in which the metallic load introduction elements are already integrated.
The process chain for manufacturing hybrid preforms from braided sleeves and the metallic load introduction elements has not yet been investigated and therefore represents the central objective of this work. Furthermore, a continuous process understanding for the process chain shall be achieved.
Therefore, in the first step of this work, requirements for the process chain are elaborated and a sequence of individual processes is developed. ... mehrThe individual processes are analysed with regard to their degree of maturity and it is determined that the steps binder application and draping represent the special focus of this work. The individual processes are analysed with regard to their degree of maturity and it is determined that the two steps of binder application and draping represent the special focus of this work.
For the binder application, a machine module is developed which is based on the vibration-assisted dispensing of binder powder. For the selection of a suitable dispensing nozzle, a model is developed which predicts the binder dispensing and thus calculates the optimum nozzle configuration. A machine module is also being developed for the draping process step, which drapes the preform onto the load introduction element by means of membrane-based forming with compressed air. A kinematic draping model is developed and validated to determine the necessary axial feed during draping. Finally, a continuous process chain consisting of all individual steps is prototyped, tested and validated on the basis of the requirements set out at the beginning.