Arc stability and its impact on weld properties and microstructure in anti-phase synchronised synergic-pulsed twin-wire gas metal arc welding

• Published in: Materials in engineering 2015-02, Vol.67, p.293-302
• Main Authors: Moinuddin, Syed Quadir, Sharma, Abhay
• Format: Article
• Language: English
• Subjects: Arc heating; Arc welding; Gas metal arc welding; Instability; Microstructure; Stability; Welded joints; Wire
• ISSN: 0261-3069
• DOI: 10.1016/j.matdes.2014.11.052

•Arc stability in twin-wire pulsed GMAW is investigated.•Current–voltage signals are analysed to quantify the arc stability.•Arc stability affects microstructures, geometry and mechanical properties of welds.•Dissimilar lead and trail currents induce arc stability. The paper conveys new observations on arc stability in anti-phase synchronised synergic-pulsed twin-wire gas metal arc welding. Unlike the conventional understanding that arcs mutually affect each other, leading to arc instability, uneven weld bead, and excess spatter loss, etc., the present investigation suggests that dissimilar currents at lead and trail wires induce stability in the welding arcs, resulting in a considerable influence on weld microstructures, hardness, heat affected zone, and weld penetration-width ratio. The separation of arcs in time by anti-synchronisation and a synergic pulse can be better utilised to control arc instability when the current at the lead wire is more than that of the trail wire.