In this research, numerical analysis was performed on CO₂ arc welding with a torch angle of 10 degrees, and the axially asymmetrical droplet formation process in a repelled transfer mode and the arc characteristics accompanying it were studied. As a result, it was found that the arc clearly separated into the dense metal vapor region with low temperature under the droplet and CO₂ arc region with high temperature under the wire tip. The general tendency of the distributions of the temperature and metal vapor mole fraction was confirmed to agree well with that in the experimental results. In addition, it was clarified that approximately 60% of total current in the wire conducted to the CO₂ arc region with high temperature through the wire tip. This result is thought to imply that the electromagnetic force available for the droplet detachment in repelled transfer significantly decreases, because the large part of the current in the wire directly conducts to the arc not through the neck between the wire tip and the droplet.

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