Parameter Dependencies of Copper Welding with Multi-kW Lasers at 1 Micron Wavelength

Copper materials gain in importance e.g. in view of the coming electro-mobility and therefore also related joining methods for well conducting, fatigue-proof, corrosion resistant and sealing connections are sought after. Welding of copper is generally considered to be difficult, particularly due to its high heat conductivity. Regarding welding with lasers the hitherto unknown coupling efficiency and fear of damaged optics, beam guidance and laser source due to back-reflections make potential users insecure. These are good reasons to systematically investigate copper welding capabilities of the latest generation of fiber-coupled lasers at powers up to 10 kW. The influence of beam power, intensity and material properties on welding depth and seam width versus speed is determined theoretically and practically.