Selective fiber deposition device
The selective fiber deposition device [in German: “Selektive Faserablage Einrichtung (SFE)”] is a planned manufacturing process in which long and continuous fibers are impregnated with resin at a speed of up to 600 mm/s. The reaction with resin is started in a controlled manner and the fiber-resin mixture with the desired degree of gelation is deposited in the tool in a consolidated manner. A product made from dry fiber and resin is thus constructed in a single production step with optimized fiber orientations adapted to the loads to which it will be subjected.
This procedure is the basis for the innovation targeted in the project. By developing, constructing and testing an applicator unit, specific aspects of the method described will be brought together in a confined space. This will demonstrate the feasibility of the SFE process.
The philosophy of this method is the consistent orientation of the fibers. This is possible if the fibers wetted with resin can be deposited and fixed on the tool appropriately for the load, i.e. along the lines of force, without facing any production-related restrictions. Starting from a continuous fiber strand – the roving – all necessary process steps are performed in a robot-guided applicator unit prior to deposition on the tool. This allows the number of steps in the manufacturing process of carbon fiber reinforced plastics to be reduced to a single integrated process step, thus eliminating entire process steps of previous techniques, such as fabric weaving and resin injection.
Figure: Carbon fiber textiles, impregnated and non-impregnated
The applicator needs to be realized to such an extent that the deposition and saturation of the fibers and the initiation of curing can be carried out by the applicator unit. This principle also allows local changes in orientation and wall thicknesses. The applicator is then to be tested in the entire system for a simple component. The findings expected during this project will help to further develop the OneStep process in order to apply cost-efficient CFRP components optimized for lightweight construction in the automotive industry in the medium term. The MAI SFE project will thus make an important contribution to the cost-effective production of mass-produced CFRP components.