Laser beam cutting is the most widespread production technique within laser material processing. Until now, CO_2-Lasers are used almost solely for laser beam cutting [1]. An excellent beam parameter product, high laser power and a high absorption rate are the most important features in order to reach high cutting speeds in combination with high cutting edge qualities. Providing the mentioned characteristics, solid state lasers of high brilliance like disk or fiber lasers which have captured the market during the last years have the biggest potential to become the lasers of choice for cutting. Studies at Fraunhofer IWS have shown, that cutting with fibre lasers is promising in order to reach high cutting rates and cutting edge qualities [2][3] [4]. Beam qualities better than 2.5 mm mrad at a wavelength of about 1 um and a laser power in the area of several kW open up new possibilities in laser processing e.g. it is possible to cut thin sheets with cutting rates more than 100m/min. However, these cutting speeds can be barely achieved with a classic machine design in particular in the case of cutting contours with small radii. Thus, the cutting speeds are currently limited by the dynamics of the used handling system. Cutting speeds limited by the ability of the laser are much higher. One alternative to overcome these limitations is described in the presented paper. This paper describes a smart solution using the advantages of high brightness lasers - the remote laser cutting. Firstly a short introduction of the process is given and the experimental equipment will be explained. A pressurized assist gas to blow out the molten material out of the cutting kerf is no longer necessary. Thereby the working distance does no longer depend on the distance between the gas nozzle and the work piece. In combination with a 2D-Scanner the laser beam is flexible in the working field of the scanner. Afterwards a thermodynamic characterization of the remote cutting process is carried out. The cutting kerf is generated by a layer by layer ablation process. However, an example shows that contour cutting speeds of about 100 m/min are possible.
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