The Institute of Aircraft Design of the University Stuttgart’s most recent project has produced one of the first Carbon and PA6 commingled yarn parts, a rear wheel arch for the Elemental Rp1. In collaboration with Coats Speciality, Shape Machining and Elemental, this complex 3D part with several corner bends was successfully created using the Tailored Fibre Placement (TFP) method.
A focus for the project was on the development of the commingled yarn and respectively draping the consolidation. Coats Speciality optimised the commingled yarn by homogeneously mixing the Carbon and PA6 fibres, enhancing its processability with the TFP method as well as other textile processes. The uniform mix of fibres led to low undulation and good impregnation of all filaments after the consolidation. Within that, high mechanical properties could be achieved delivering the perfect balance between strength, weight, performance and also recyclability.
Another focus for the project was on proving complex 3D structures could be manufactured using the TFP process. Shown as successful through the production of the rear wheel arch for the Elemental Rp1, it is one of the first parts of its type to be tested on the road and utilized in a high performance automotive.
The wheel arch is made in four easy steps. Carbon fibre and polyamide 6 fibre are uniformly mixed together to create a single thermoplastic commingled yarn. The yarn is then embroidered into a near net shape using the Tailored Fibre Placement (TFP) preforming process. Once the shape is precisely layed-up, it is then draped in the machine mould and pressed to form in less than 60 seconds. Final parts are finished to a high standard without using thermoset resins or autoclave.