The Clean Sky 2 plan IMCOLOR project has developed a new manufacturing process that combines the multi-needle injection molding process with integrated continuous carbon fiber reinforced materials, and uses consumable salt core materials (which can withstand injection loads), which can be used for light and environmentally friendly Production of air circulation machine parts.
According to relevant partners, the synergistic effect formed between injection molding and thermoplastic automatic fiber placement and in-situ curing (TP-AFPisc) will promote future designs, namely, lightweight, high mechanical performance, automation, and easy-to-replicate production technology. TP-AFPisc is said to be different from the current state-of-the-art technology. The composite structure is usually built in the process chain. In addition, the partners noticed that through the use of parts manufactured by TP-AFPisc, the fiber structure is precisely adapted to the needs of users, reducing the effort of trimming composite parts and reducing scrap.
It is reported that this new technology also brings some additional benefits. For example, there is no need for hexavalent chromium ion (Cr6+) treatment in the production process-chromium is the most toxic and has a negative impact on the environment. In addition, with the integration of thermoplastic materials, parts produced through this process will increase efficiency, reduce fuel and emissions, be recyclable, and retain environmentally friendly process auxiliary materials.
Some of the challenges facing the IMCOLOR project include finding suitable cavity design and injection parameters to embed carbon fiber reinforced polymer (CFRP) into the injection molded polymer. According to the project partners, it is difficult to find a suitable combination of materials to promote a good bond between the CFRP liner and the polymer. During the high-pressure injection process, the CFRP gasket must also be properly fixed so that it will not be deformed or misaligned.
An unexpected finding was that there were out-of-plane wrinkles on the 23 layers (3 mm thickness) on the model parts. The partners believe that this may be due to the play between the mold core and the insert. However, this effect did not occur in the demonstration part of the 70-layer insert (10 mm thickness).
The next step of the project will be the further investigation of the new material combination and the evaluation of the new internal process. The research team will also study the potential of salt cores for composite material production and metal casting processes in internal and subsequent projects.
Participating partners in the project include Liberty Boherer Aerospace Toulouse SAS, Technical University of Munich, Germany, the Netherlands Thermoplastic Composites Research Center, Apppex GmbH of Germany and FACC Advanced Composite Components in Austria. The total amount of EU funding is 254,775 euros.