In which transfer mode does the power supply alternate between high and low current cycles?

The pulse-spray transfer mode is characterized by the power supply alternating between high and low current cycles. In this mode, the welding machine delivers bursts of high current, which allows for the transfer of droplets of molten metal across the arc to the workpiece, followed by low current periods that reduce the heat input and control the weld pool. This cyclical variation in current not only enhances control over the weld bead’s shape and penetration but also minimizes spatter and provides a finer, more stable arc.

In the context of advanced GMAW techniques, pulse-spray transfer is particularly advantageous for welding thicker materials or in conditions where heat control is vital. The ability to adjust the current helps in managing the thermal input, leading to cleaner and more precise welds, as well as improved mechanical properties of the weld joint.

The other transfer modes mentioned do not incorporate the alternating current cycles that define pulse-spray mode. Globular transfer typically involves a steady flow of metal without significant control over droplet size, while short-circuit transfer operates at low current with a different mode of interaction between the electrode and workpiece. Axial spray transfer is not recognized as a standard transfer mode in GMAW and does not exhibit the same current cycling characteristic as pulse-spray