The study on arc stability and welding formation in the single-power double-wire welding process with different inter-wire spacing.

To mitigate interference between double arcs and improve arc stability, a double-wire single-arc welding methodology was employed. This study systematically examined the effects of inter-wire spacing on arc behavior, droplet transfer, welding formation, and microstructures. At spacings below 4 mm, a coalesced arc configuration was observed, wherein droplet transfer occurred through the singular detachment of droplets resulting from the combined melting of both electrodes. When the inter-wire spacing increased to 6 mm, distinct double arcs formed, with independent droplet transfer occurring from each wire. Due to the increase in surface tension and the change in the direction of the electromagnetic force, the transfer size of the double-wire single droplet has significantly increased. Arc interference at 6 mm and liquid bridge breakage at 2 mm resulted in instability in the single-power double-wire welding process, which was accompanied by excessive spatter generation. At 4 mm spacing, welding process stability improved, enabling double-wire welding with reduced spatter.