Fraunhofer Institute for Microstructure of Materials and Systems IMWS
Fraunhofer Institute for Microstructure of Materials and Systems IMWS

Tape-based thermoplastic lightweight structures

© Fraunhofer IMWS
Thermoplastic 3D tape-laying system used for the manufacture of a patient-specific fiber-reinforced orthosis
© Fraunhofer IMWS
Thermoplastic 2D tape-laying system for the manufacture of a load- and material-optimized tape laminate (tailored laminate)

High mechanical properties combined with low weight, along with suitability for large series production and recyclability: This combination makes thermoplastic tape-based lightweight structures so attractive for high-volume applications such as in the automotive industry. But also in other industries such as aerospace the demand for thermoplastic approaches is increasing, due to the growing importance of circularity and automatability. Continuous reinforcement fibers with high stiffness and strength properties (made of glass, carbon, or even hemp) are combined with a thermoplastic matrix to form thin, unidirectionally reinforced individual layers (UD tapes), that exhibit very high mechanical properties in the fiber direction. In a subsequent step, the individual UD-tape layers are bonded together to build up a laminate, with the orientation of the individual layers optimized according to the later load conditions on the component.

© Fraunhofer IMWS
Component testing and validation of an optimized tape-based lightweight structure using the example of a front-end module for automotive applications
© Fraunhofer IMWS
Development of industrial-ready process and automation concepts using the example of child car seat manufacturing via hybrid injection molding and thermoforming of a thermoplastic composite laminate, utilizing a preform gripper to achieve complex forming operations

Research and further development of thermoplastic tape-based lightweight structures through material and process engineering approaches is one of the key research areas at Fraunhofer IMWS. In particular, we offer innovative approaches both for the development of property-optimized tape semi-finished products as well as for the design and manufacture of tape-based lightweight structures. In hybrid manufacturing processes, the thermoforming of continuous-fiber-reinforced composite laminates can be combined with the injection molding of short-fiber-reinforced thermoplastics. Thereby the advantages of each thermoplastic group (high mechanical properties / complex shaping & cost-effective manufacturing) can be optimally used for the mass production of lightweight components. Further processing and application possibilities arise from thermoplastic tape winding as well as 2D and 3D tape laying process for the manufacture of load- optimized, material-efficient, and tailored laminates and components. Our expertise includes, in particular:

  • Component Development and Design: component design optimized for load-bearing capacity and manufacturability, using process and structural simulation;
  • Development and optimization of process and automation concepts: Hybrid injection molding technology combined with thermoforming of composite laminates, 2D tape laying for the manufacture of tailored laminates, 3D tape laying for the manufacture of load-optimized components—even for small series quantities —in combination with 3D printing, and tape winding for the production of load-optimized rotationally symmetric components;
  • Validation of component demonstrators: Manufacture of prototypes, pilot series, small- series production, and sample runs; testing and validation
  • Evaluation: Testing of tape-based lightweight structures and semi-finished products;
  • Material development: Development and production of property-optimized tape-based semi-finished products with a focus on high-performance materials and sustainable materials based on bio-based and recycled components.

 

At Fraunhofer IMWS, particular attention is paid to the relationship between the material, processing influences, and the resulting material properties. Process engineering tasks are carried out from the laboratory up to the pilot scale, enabling a flexible and rapid transfer of development results into industrial applications.