Approaches for increasing process rate of local 3D laser decoating for series production of hybrid composites

Laser structuring of tool surfaces with circular spots and diameter below 30 μm as well as laser decoating with line spots above 50 mm are established in industry. For the fulfilment of processes with intermediate requirements, e.g. local laser pretreatment on 3d surfaces of carbon fiber-reinforced plastics (CFRP) for subsequently intrinsic joining, an established technology is missing. Attuned robot and scanner systems with high flexibility and sufficient accuracy, as well as application oriented path programming and a methodology for shorting cycle times are missing. A new integration approach enables for the first time an overlapping workspace of injection molding machine and robot-guided 3d laser scanner for in-mold processing, adaptable to a wide range of polymer processing machines worldwide. Large-area surface processes at components with a production volume >30.000 pc./a require efficient path generation and processing. Supplementary to the 3d segment process developed by Fraunhofer Institute for Production Technology IPT tools are developed for scalable robot-guided decoating process. With respect to scan field size and angle of incidence a software is set up, which inherently allows a free implementation of genetic algorithms for finding a sufficient solution with the minimal number of scan fields and the corresponding optic positions. Furthermore, process optimization is done by a systematical analysis of resin ablation and heat affection using NIR short pulses at single spots, lines and rectangular. The conflicting objectives of increasing adhesive strength and decreasing cycle time for the specific FRP application is analyzed and quantified.