Influence of different configurations of assisting gas in high-power cw-CO2-laser welding

In high power cw-CO 2 -laser welding, assisting gas is necessary. It has a great effect on the welding results, such as penetration depth, cross section, size of the heat affected zone and welds surface. Much has been done on discussing the influence of its kind and flow rate on the welding results, but little attention was given to its configurations. In this article, several configurations of assisting gas were tried and the according welding results were given. Especially, a new gas assisting configuration including three gases was suggested. Their influences on the topography and cross sections were qualitatively analyzed. Experimental results showed that the best welds were obtained with the new three-gas-configuration.