Fibre-reinforced plastics (FRP) are considered one of the central material classes within the fast-growing lightweight construction sector. Particularly in the industrial sectors of transportation, mobility and construction, the demand for glass fiber reinforced plastics (GFRPs) has now been growing for several years.
In this "C³ - ColdCureComposites" project, the Fraunhofer IPT is developing production technologies for the manufacture and further processing of a new, cold-curing composite. The so-called GFRP towpregs (pre-impregnated glass fiber tows) are suitable for a particularly wide range of products and can be further processed into lightweight structures using lay-up or winding processes.
Through the use of a new resin formulation to be developed and the use of UV- and VIS LEDs as an energy source for chemical curing of the matrix material, the project partners hope to achieve significant energy and cost savings compared to conventional fiber-reinforced composites, which achieve their final strength by applying heat. By integrating UV-LEDs into existing winding or lay-up processes, the towpregs can be processed with high production and energy efficiency, e.g. into lightweight structures, with complete consolidation within a few seconds. Just like the production of thermoplastic components using the tape-laying process, this enables in-situ consolidation and eliminates the need for costly autoclave processes. The towpregs are sealed with a lightproof film to ensure long term storage before the semi-finished products can are finally processed - yet another advantage over classic FRP semi-finished products with thermoset matrix.
The material properties of the new semi-finished product will be characterized by the project partners during further processing in the Automated Fiber placement process (AFP) and with the aid of standard tests. Finally, the photocure composite will be validated using industry-relevant demonstrators.