5. Derivative processes

Pulsed-current MIG/MAG processes

Derivatives of the MIG/MAG process are based on developments in current generators, enabling us to work with pulsed waveforms whose polarity remains fixed. The aim is to control metal transfer by generating one drop per pulse. This mode combines the advantages of short-circuit transfer, i.e. a reduced bath that can be controlled by the welder, with those of axial spray transfer, with a penetrated bath and therefore greater weldable thicknesses. The principle is as follows: the welding current is successively given a high value, to achieve transfer by axial spraying, and a low value, sufficient to ensure arc maintenance, such that the average current value is characteristic of transfer by short-circuiting. Four basic parameters drive the signal: maximum peak current (I _peak ...