LASER CUTTING METHOD AND LASER CUTTER

摘要

A laser cutting method and a laser cutter which meet the demand for preventing adverse effects by self burning or the like on cutting surfaces particularly during high-speed cutting. A laser cutting method in which a cutting laser beam (22) is applied to a material (25) to be cut at a cutting point (26) while ejecting gas streams (23, 24) against the cutting point (26) or its surrounding area from a plurality of nozzles (30, 31) arranged in a ring or in line, wherein the oxygen concentration of the gas streams (23, 24) flowing out of at least one of the nozzles (30, 31) is changed to adjust the oxygen concentration distribution in an area within several millimeters of the cutting point (26). This method and the laser cutter can limit the adverse effects by self burning or the like and improve the cutting quality.