Product Code: PIC06_901

High-Speed and Camera Based Temperature Measurement and Control for High Power Laser Scanning Systems
Authors:
Berndt Brenner, Fraunhofer Institute for Materials & Beam Technology; Dresden Germany
Eckhard Beyer, Fraunhofer Institute for Materials & Beam Technology; Dresden Germany
Marko Seifert, Fraunhofer-Institute Material & Beam Technology; Dresden Germany
Steffen Bonss, Fraunhofer Material & Beam Technology; Dresden Germany
Jan Hannweber, Fraunhofer IWS; Dresden Germany
Presented at PICALO 2006

Laser beam scanning systems, designed by Fraunhofer IWS Dresden, for heat treatment of metals with high power diode lasers are used in industrial scale since last year. With 4 kW laser power 40 mm wide hardening tracks are possible. To meet the demands of customers a new processing head has been developed. New features, like the compact size, flexible beam direction and a variety of integrated temperature sensors make the processing head ideal for industrial application with many types of high power diode or Nd:YAG lasers in the multi-kilowatt range. Special hardware and software tools have been developed to simplify the handling of the complex system. One special feature is a user defined adjustment of laser intensity profiles in one direction. To watch and control heat treatment processes, fiber-coupled high-speed pyrometers and low cost CCD camera based temperature measurement devices are used. Especially low cost IR-sensitive camera systems show currently a very strong development. The latest prototype is able to acquire the full 2D- temperature information from the process with a sample rate of 120 Hz and VGA resolution. The connection to closed-loop controllers is possible and necessary for reliable industrial processes. The latest status of the developments and results of heat treatment applications are presented.