Product Code: ICA11_M1102

Picosecond Laser Ablation of Carbon Fiber Reinforced Plastics at Different Wavelengths
Authors:
Alexander Wolynski, Photonik-Zentrum Kaiserslautern (PZKL); Kaiserslautern Germany
Thomas Herrmann, Photonik-Zentrum Kaiserslautern (PZKL); Kaiserslautern Germany
Michael Schmidt, Lehrstuhl fur Photonische Technologien (LPT); Universität Erlangen Germany
Johannes L'Huillier, Photonik-Zentrum Kaiserslautern (PZKL); Kaiserslautern Germany
Presented at ICALEO 2011

Carbon fibre reinforced plastics (CFRP) offer outstanding mechanical properties at extraordinarily low weight for the optimization of structural parts in aircraft and increasingly in automotive industries. The ultra-fast laser machining technology offers a promising tool for the high quality CFRP manufacturing. The heat affected zone (HAZ) as one of the quality criteria can be significantly reduced by using picosecond laser pulses and optimized process strategies. But further increase of the process throughput while maintaining quality is required to make the picosecond laser machining of CFRP a competitive manufacturing technology. However, previous works showed the quality and time trade-off. In addition to the laser fluence, the feed rate and the pulse repetitions rate the laser wavelength is a critical parameter for process optimisation. This is well known from ultra-short laser processing for materials other than CFRP. For industrial applications picosecond laser are available at a fundamental wavelength around 1 µm and its harmonics in the visible and UV. Hence we focused our experiments on these wavelengths. In this report a detailed experimental comparison of the processing of CFRP at laser wavelengths of 1064 nm, 532 nm, and 355 nm will be presented. The decreasing HAZ for shorter wavelengths as well as the ablation rates for the different laser wavelengths will be discussed.