PROCESS FOR THE LASER BEAM CUTTING OF STRIP OR PLATE WORKPIECES, ESPECIALLY MAGNETIC STEEL SHEETS

摘要

The invention relates to a process for the laser beam cutting of strip or plate workpieces at high speed, especially over 100 m/min. The laser beam melts the workpiece with the formation of a vapour capillary at the cutting point and the melt is driven off by a cutting gas consisting of an inert gas/hydrogen mixture. In order to maintain the vapour capillary, the hydrogen component of the cutting gas mixture is set so high and this cutting gas mixture is taken to the surface of the melt at the cutting point at such a pressure and with such a pressure distribution that the temperature at the surface of the melt is kept at boiling point and the melt is continuously driven out of the cutting seam on the side away from the cutting direction of the vapour capillary.