| 摘要 |
PROBLEM TO BE SOLVED: To enable laser welding to have deep penetration with blowholes prevented from generating by using a shielding gas in which argon gas is mixed with oxygen at a specific volume percent. SOLUTION: The subject welding method employs a shielding gas in which argon gas is mixed with oxygen at 2-5% in volume percent. The shielding gas mixed with oxygen increases fluidity of a weld metal and decreases blowholes; however, with oxygen 2% or less, the effect is reduced, and with 5% or more, the effect undesirably comes close to laser cutting because of oxidation by oxygen. Thus, an improved weld zone is obtained having less blowholes. By mixing oxygen in argon gas, an oxide is produced on the surface of a material to be welded, thereby improving the absorptivity of a laser beam and deepening penetration. |
