Abstract
Carbon dioxide gas-shielded arc welding, which is widely used in industry, generates a large amount of spatter in the medium and high current range. To solve this problem, we developed a new welding process with low spatter and low gas cost that we call “Pulsed Gas MAG” (PGMAG) welding. In PGMAG welding, the metal transfer is controlled by the suitable addition of Ar gas, but the effect of the welding current has not been clarified. Therefore, we investigated metal transfer in the 235- to 325-A range and found that the pulse frequency of Ar gas must be adjusted between 35 and 65 Hz to match the welding current (i.e., wire feed rate) to control metal transfer. A wide area where metal transfer is controllable is obtained by adjusting the Ar addition frequency for a current of 235-325 A. It was considered that there is a suitable volume for the droplet to be released and that the growth speed depends on the wire feed rate.
