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.