No abstract

Fibre reinforced plastics (FRP) are being increasingly used for advanced applications where an appropriate mechanical performance should be achieved at minimum weight. A substantial increase of the FRP usage is expected across various industries e.g. in automotive sector in the nearest future. This leads to the mass manufacturing of FRP components. Reduction of manufacturing costs of FRP components is regarded as the main enabler for the usage of this material in mass production. Although FRP components are manufactured near-net-shape, they often have to be pierced or trimmed in one of the last manufacturing steps. With rising production numbers blanking is a potentially more cost efficient technology for trimming and piercing of FRP components compared to the conventionally performed abrasive water jet cutting or machining. The mechanisms of FRP separation in blanking have not yet been researched. In particular, the influence of the fibre orientation relative to the cutting line on the cutting force is not known. In the scope of this work an experimental study of blanking of a unidirectional carbon fibre reinforced plastic with a thermoset resin at different fibre orientations to the cutting line was performed. It was shown that the cutting force decreases from the perpendicular to the parallel fibre orientation to the cutting line. A possible mechanical explanation of this dependency was formulated.

Due to a high specific strength, carbon fibre reinforced plastics (CFRP) enable material driven light-weighting of structural components. A constant increase of CFRP usage is predicted to continue in the future. At high production numbers blanking can be cost efficiently used for piercing or trimming operations of cured CFRP components. Compared with metals, sheared edges of blanked CFRP demonstrate fundamentally different morphology. Therefore, conventional characterization parameters cannot be used for an unambiguous characterization of the sheared edge quality. In the scope of this work, surface profile parameters were adopted for this purpose. The applicability of the quality parameters was successfully shown on the example of experimentally produced sheared edges. Furthermore, it was demonstrated that the proposed sheared edge quality parameters enable the quality assessment under process inherent variability of the sheared edge morphology in CFRP.