MECHANICAL CHARACTERISATION OF IN-SITU BONDING BETWEEN PEEK FILAMENTS AND LAMINATES IN THE FFF PROCESS

Fused filament fabrication (FFF) of high-temperature, aerospace-grade thermoplastics like PEEK has made significant progress in recent years and has become an established process for 3D-printing of complex parts. However, possibilities of adding long or continuous fibres are still limited and the introduced thermal stresses limit the maximum part dimensions. To overcome these limitations, this work investigates the potential of bonding FFF printed parts in-situ onto continuous fibre reinforced laminates. This process allows the combination of the complexity of 3D-printing with large scale manufacturing processes for high-performance structures. The investigation is divided in two steps. Firstly, the effect of process temperatures on the inter-layer bonding of printed PEEK is investigated. On this basis, the optimal process parameters for the bonding of printed PEEK onto PEEK laminates are analysed. The results show a strong correlation between the process temperatures and the inter-layer bonding as well as the bonding between filament and laminates. The process influences shown form the basis for future hybrid component and process designs