Droplet Transfer Modes for a MIL 100S-1 GMAW Electrode

摘要

Welds were made with a 1.2-mm-diameter MIL 100S-1 electrode using Ar-2% O2shielding gas to investigate the effects of contact-tube-to-work distance (13, 19, and 25 mm) on metal transfer. The transfer modes were identified by the sound of the arc, images from a laser back-lit high-speed video system, and digital records of the voltage and current fluctuations. The spray transfer region was mapped on a current-voltage plot, with a range that included the boundaries of adjacent transfer modes. The metal transfer mode boundaries shifted with an increase in contact-tube-to-work distance. Increasing the contact-tube-to-work distance from 13 mm to 19 mm required a 15 mm/s increase in the wire feed rate for the globular-to-drop-spray transition.