Laser welding with high power lasers combining system

We have developed the high power laser beam combining system with the 10kW class chemical oxygen-iodine laser (COIL) of wavelength 1.315µm and the 6kW class Nd:YAG laser of wavelength 1.064µm. The characteristic of the beam propagation, the combining beam quality and the optics were evaluated. The combining beam providing power was up to over 16kW. The combining beam was used for laser welding of the thick SUS304 stainless steel (10∼20mm) plates. The effects of various welding parameters which were the laser powers, the shielding gases, the welding speeds, the focus positions, welding postures were investigated. The high quality welding results for the 15mm thick SUS304 plates were obtained.