Abstract
Gas Metal Arc Welding (GMAW) under pure Argon shielding gas atmosphere (pure Argon-GMAW) is suitable to obtain a high-strength and high toughness welded joint. However, it is difficult that pure Argon-GMA welding is applied practically welding structure because of arc instability. In order to perform stable pure Argon-GMA welding, duplex current feeding GMAW (DCF-GMAW) has been developed. The DCF-GMAW consists of primary GMA welding current and secondary welding current by constant-current power resource. DFC-GMAW can feed larger current near wire tip. This effect makes that weld penetration depth is deeper, weld bead shape is improved using DCF-GMAW.
