AC (alternating current) enables us to TIG weld non ferrous alloys like Aluminium, Magnesium and Alumin-
ium Alloys. These materials have an insulating surface oxide layer that melts at a higher temperature than
is ideal because the nature of the AC wave form assists in breaking the surface oxide layer.
The reversing of the polarity breaks the surface oxide while the direct polarity melts the base material.
stoppage. These problems typically occur during the transition between + and - cycles.
makes the AC arc unstable.
fed into the welding circuit. The HF maintains the arc stability during the half cycle when the electrode is
area in an ionized state. When the arc is ionized the arc is maintained during the half of the cycle when the
producing an unbalanced wave.
UNBALANCED WAVE FORM