Numerical Analysis on Influence of Electrical Conductivity of Wire on Droplet Temperature in Duplex Current Feeding MIG Welding

MIG welding under pure argon shielding gas atmosphere (pure argon-MIG welding) is suitable to obtain a high-strength and high toughness welded joint. However, it is difficult to apply pure argon-MIG welding practically to welding structure because of arc instability. In order to perform stable pure argon-MIG welding, duplex current feeding MIG welding has been developed. The duplex current feeding MIG welding consists of primary MIG welding current by constant-voltage power source and secondary current by constant-current power resource. In previous experimental study, it was found that the temperature of a droplet by duplex current feeding MIG welding was higher than the conventional MIG welding. In this paper, influence of electrical conductivity of the wire on basic characteristics of duplex current feeding MIG welding are discussed by numerical analysis. Consequently, it was clarified that the increase in the droplet temperature in the duplex current feeding MIG welding was significant especially in case of a wire material with lower electrical conductivity.