| 摘要 |
PROBLEM TO BE SOLVED: To provide a weld joint less in impurities and high in quality with high productivity by performing the gas shield by a gas mixture of oxygen and argon of a specified composition, and performing the MIG welding in a spray mode or a pulse mode without current modulation. SOLUTION: The MIG welding of aluminum or its alloy is performed using a gas shield in at least a part of a welding zone in a non-modulating spray mode or pulse mode. A gas mixture consisting of 0.01-1.80% oxygen, 98.20-99.99% argon, preferably 0.5-1.8%, more preferably, 1-1.7%, and further more preferably, 1.2-1.65% oxygen, and the balance argon is used for the gas shield. The MIG welding is preferably performed under the condition that the welding speed is 0.25-1.20 m/minute, the wire feed speed is 2.5-20 m/minute, the mean welding current is 40-450 A, and the mean welding voltage is 15-40 V, using a solid meltable wire or a cored arc wire. |
