Product Code: ICAL07_208

Welding and Cutting of Copper with High Brightness Lasers
Authors:
Eckhard Beyer, Fraunhofer IWS; Dresden Germany
Peer Pfohl, Fraunhofer IWS; Dresden Germany
Patrick Herwig, Fraunhofer IWS; Dresden Germany
Ralf Imhoff, Fraunhofer IWS; Dresden Germany
Presented at ICALEO 2007

When using a fiber laser for the processing of copper or other high reflecting materials we have to take care of the back reflection. If we used a polarized laser with wave lengths in the range of 1 µm, it would be relatively easy to build up an optical diode to block optical feedbacks by using the Farrady isolator (rotator) or the Lambda/4 window. That system can also be used in order to increase the beam power and power density at the workpiece. The presentation will show the effect of optical feedbacks during cutting and welding with the fiber laser, how those feedbacks could be reduced and how they have to be used to optimize the cutting or welding process. On the other hand the presentation will show the influence of the Brewster effect for applications with the fiber laser. Those effects will be explained from the physical basics to industrial applications.