A comparison of single and twin tungsten electrode – wire electrode IAW

ABSTRACT

Twin tungsten electrode – wire electrode indirect arc welding (TTW IAW) was a novel welding method. In this paper, the wettability and spreading of weld bead of TTW IAW were investigated by comparing with single tungsten electrode – wire electrode indirect arc welding (STW IAW). Results showed that compared to STW IAW, TTW IAW possessed larger arc width and greater arc heat distribution range with smaller variation gradient, due to the lower velocity of charged particles toward the arc center, caused by the smaller electromagnetic force acting on the arc plasma. So did the temperature distribution of weld pool of TTW IAW. Moreover, the process stability of TTW IAW was better. Besides, at the molten pool front, the transverse convection of the melted metal of TTW IAW was adequate, because of the superior wettability and long flow duration of the melted metal; at the molten pool rear, the inward convection of the melted metal of TTW IAW was weak mainly owing to the low Marangoni force. Therefore, the weld bead width of TTW IAW increased by about 25.0% and the wetting angle of the weld bead decreased by about 25.7% compared to STW IAW, which indicated that the weld bead spreading of TTW IAW was better.

KEYWORDS:

• TTW
• IAW
• weld
• bead
• spreading
• arc
• heat
• distribution
• transverse
• convection

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (No. 52175290)