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tp-Pulse peak time
T-Pulse period
Pulse TIG includes all DC TIG parameters, except that the parameters are set differently. The
parameters will not be explained again here. In addition, there are 4 adjustable parameters,
which are explained separately in conjunction with the figure:
● Peak current (Ip): Maximum pulse current, adjusted according to the process requirements.
● Base current (Ib): Minimum pulse current, adjusted according to the process requirements.
● Pulse frequency (1/T): T=tp+tb, adjusted according to the process requirements.
● Duty cycle (100%*tp/T): the percentage of peak current duration in the pulse cycle,
adjusted according to the process requirements.
7.3.3 AC TIG
AC TIG welding current waveform
I1-Initial current
t2-Up-slope time
I3-Set AC peak current
t4-Down-slope time
I5-Finish current
tc-Cleaning current time
T-AC period
AC TIG supports square, triangular and sine output waveforms. AC and DC TIG have the
same pre-flow time and post-flow time, but the other parameters are explained separately in
conjunction with the figure:
● Initial current (I1), peak current (I3) and finish current (I5): These three parameters are set
approximately equal to the effective values of the actual welding current, and can be adjusted
as required.
● AC frequency (1/T): Can be adjusted as required.
● AC balance (100%*tc/T): Generally, the current of the positive tungsten electrode in AC
welding is called the cleaning current. Its main function is to break the dense oxide layer of
the workpiece, and AC balance represents a portion of the cleaning current, generally
