Experimental measurement of fluid flow in high-speed GMAW assisted by transverse magnetic field

• Published in: Journal of manufacturing processes 2020-08, Vol.56, p.1193-1200
• Main Authors: Wang, Lin, Wu, Chuansong, Chen, Ji, Gao, Jinqiang
• Format: Article
• Language: English
• Subjects: High-speed welding; Humping bead; Liquid metal flow; Transverse magnetic field; Visual measurement
• ISSN: 1526-6125; 2212-4616
• DOI: 10.1016/j.jmapro.2020.06.006

•2D liquid metal flow velocity on weld pool surface was measured by the tracer particle.•Humping bead phenomenon was experimentally investigated by visual measurement.•The effect of transverse magnetic field on fluid flow behavior in high speed gas metal arc weld pool was analyzed. The visual measurement system was established to investigate the fluid flow during high-speed gas metal arc welding. The two-dimensional fluid flow velocity on weld pool surface was measured using the tracer particles. The characteristic parameters of the backward liquid metal flow were extracted, then the speed of the liquid metal flow was compared with different welding speeds. The results showed that the high-speed backward liquid metal flow and the pinching & earlier solidification of the backward liquid metal flow channel caused the humping bead formation. A transverse magnetic field was used to control the fluid flow behavior to prevent the humping bead. Due to the introduction of transverse magnetic field, the thickness of liquid metal layer underneath the arc was increased. The longitudinal velocity of the liquid metal flow was decreased while the transverse velocity was increased so the humping bead can be suppressed.