1st International Conference on Innovative Academic Studies, Konya, Turkey, 10 - 13 September 2022, pp.1
Automated fiber placement (AFP) is an advanced manufacturing process, allowing large-scale and rapid composite structure fabrication without scarifying accuracy using aerospace-grade carbon fiber reinforced prepregs. However, one of the process limits is the occurrence of unexpected process-induced defects in the prepreg tows during the lay-up process such as gap and overlap defects, resulting in a decrease in the mechanical properties of the composites. Producing defect-free parts or minimizing the effects of the defects can be achieved by optimizing the process parameters without interrupting the fabrication process. To determine the optimum process parameters, a clear understanding needs to link between process parameters and the defects. This study aims to investigate the influence of process parameters, including lay-up speed and compaction force, on the mechanical performance of carbon fiber/polyether-ketone-ketone (CF/PEKK) composites. For this purpose, gap/overlap defects embedded composite laminates were produced with two different lay-up speeds (0.1 m/s, 0.4 m/s) and compaction forces (300 N, 600 N). The effects of the parameters were examined in detail with differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR[VE1] ), dynamic mechanical analysis (DMA), and short beam shear tests. The optimum process parameters were determined as 0.1 m/s, and 600 N in the AFP process regards the comprehensive tests and analysis results. In case of a possible gap and overlap defect during the laying process, the effect of defects can be minimized if the compaction force is set to 600 N and the lay-up speed is 0.1 m/s on the adjacent layer.