Laser welding apparatus for a high-power laser with high beam quality and long focal-length focussing optics

摘要

A laser welding device (1) has laser that generates laser beam (2); optics (4) defining a focal length of =200 mm, and configured to focus the laser beam onto a processing zone (3a) of a workpiece (3); and a limiting apparatus (6) that limits a mixture (5) of welding gases and heated ambient air, produced during laser welding, within the laser beam to a region that is less than the focal distance away from the workpiece. An independent claim is also included for a laser welding method including generating laser beam from a laser; focusing the laser beam onto processing zone of workpiece to weld the workpiece in the processing zone, by passing the laser beam through optics defining a focal length; and limiting the mixture of welding gases and heated ambient air, produced during laser welding, within the laser beam to a region (7) between the optics and the workpiece without preventing oxidation of the workpiece within the processing zone.