Fraunhofer Institute for Production Technology IPTResearch project "Tempered"
Thermoplastic materials are recyclable but difficult to process
Thermoplastic fiber-reinforced composite parts offer great potential for sustainable lightweight construction applications: Unlike thermosetting materials, they can be remelted, reshaped, and recycled to a high standard multiple times without losing their mechanical properties. Nevertheless, industrial companies have so far made only limited use of thermoplastics. Uncontrolled temperature profiles, inhomogeneous residual stresses, and low processing speeds impair component quality and complicate the cost-effective production of large structures.
This is precisely where the project Tempered comes in: Researchers at Fraunhofer IPT are developing and validating a new technology for position-dependent temperature control that selectively heats thermoplastic fiber-reinforced components during manufacturing, thereby significantly improving quality, process speed, and sustainability.
Selective heating for better processability
The new technology combines heating via a laser or an infrared emitter with a two-dimensional temperature measurement system and can be integrated into existing production lines. Using this system, the researchers are able to precisely control the temperature of the laminate surface and continuously adjust it during the process.
Targeted heating improves the melting of the tape and substrate, induces controlled crystallization, and reduces internal stresses in the component. This allows both the process speed to be increased and energy consumption to be reduced.
Unlike conventional autoclave processes, which cure the entire component under high pressure and high temperature, the new method heats only the relevant areas during the winding or AFP process. Since the component chamber does not need to be fully heated, the result is a significantly more energy-efficient manufacturing process.
Patent validation for the new production process
A patent has already been filed for the process, which expands existing tape-laying and winding technologies by adding a previously missing, central process step. In the project, the researchers are defining the technical requirements, selecting suitable systems, integrating them mechanically and in terms of control technology, and subsequently validating the technology using demonstrator components. With this development, Fraunhofer IPT is tapping into considerable economic potential, as the new temperature control technology makes the processing of fiber-reinforced high-performance materials more sustainable, energy-efficient, and industrially attractive.
Funding
The project Tempered is funded by the European Union and the state of North Rhine-Westphalia as part of the EFRE/JTF funding measure NRW Patent Validation.
Funding code: EFRE-20801169
Project sponsor: PTJ Projektträger Jülich