High speed removal and structuring of surfaces in the automotive industry with a new diode pumped high average power Q - Switch solid state laser source

High power solid state lasers have been established as a powerful tool for surface treatment. While commercially available lasers for the removal of coatings and structuring of surfaces provide average Q - switched laser powers up to 150 W a new developed, diode pumped laser source delivers average Q - switched laser powers up to 400 W with a beam parameter product (BPP) better than 10 mm x mrad. The new laser source delivers peak powers up to 362 kW. Pulse repetition rates from 15 to 30 kHz allow high scanning speeds. An important advantage of the solid state laser is the fiber delivery of the laser power which allows easy process integration. A 300 mu m core diameter fiber with a numerical aperture of 0.2 is used for power delivery. The demonstrated improvements in processing speeds open new fields for industrial surface treatment like degreasing of metal parts, removal of lacquer and structuring of metal surfaces. Scaling the processing speed with average power has been demonstrated leading to an economical process which is very attractive especially for automotive industry. The investigations have been carried out with hand held as well as CNC - controlled laser beam scanning systems. The high processing speed in combination with environmental aspects such as no need of additional abrasives and chemicals lead to a high attractiveness of the described laser technique.