Compatibility Chart

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AC Pulse
Lincoln Electric has recently introduced a process that uses alternating current (AC)
for GMAW. This is done by adding an Advanced Module, see Figure 5-4a and b, to any
of the latest generation Lincoln Electric power supplies. The advantage of this process
is that in GMAW, direct current electrode positive (DCEP) increases heat input and
penetration while direct current electrode negative (DCEN) reduces heat input and
increases weld deposition rate. Lincoln Electric has developed AC GMAW waveforms
for aluminum by adding an EN pulse at the end of each EP pulse, see Figure 5-5.
Figure 5-4a: Power Source with Advanced Module
Figure 5-4b: Power Source with Advanced Module
GMAW of Aluminum Alloys
............................................................................................................................................................
Waveform
1
2
3
Peak
Propels droplet toward
the weld pool.
Positive Background
Completes droplet transfer
and begins the creation of the
next droplet.
Negative Background
Reduces heat input by
redirecting current flow
towards the electrode.
AC Aluminum Pulse
Figure 5-5: AC GMAW Waveform