Product Code: ICAL09_M101

Multi-100 W Average Power Ffs-Laser for Material Processing Applications
Authors:
Dirk Wortmann, Lehrstuhl für Lasertechnik, RWTH Aachen University; Aachen Germany
Torsten Mans, Fraunhofer Institut fuer Lasertechnik; Aachen Germany
Johannes Weitenberg, Lehrstuhl fuer Lasertechnik, RWTH Aachen University; Aachen Germany
Presented at ICALEO 2009

The InnoSlab laser design, already established for neodymium doped laser materials, was applied to ytterbium doped laser materials. Nearly transform limited sub-picosecond pulses at 400 W average power at room temperature and without using CPA technique have been achieved so far. This compact, diode-pumped Yb:YAG InnoSlab fs-oscillator-amplifier system, scalable to the kilowatt range was applied for ablation, cutting and drilling of various materials. Processed materials are carbon and oxide based ceramics like SIGRADUR®, CSiC and fiber-reinforced aluminum oxide, pure metals and alloys like copper, aluminum, NiAl and CMSX, and dielectrics like glass and sapphire. The samples are investigated by light microscopy and SEM, cross-sections are prepared. For the cutting and drilling experiments pulse energies of about one micro-joule and varying repetition rates between 1 and 76 MHz are used. Comparative experiments on the same materials are performed using a cw-fibre-laser. The influence of the repetition rate and the scanning velocity on the efficiency and quality of the structuring results are investigated. An estimation of the optimum process parameters repetition rate and scanning velocity for the ablation process for different materials will be given.