|
Abstract: In variable plasma arc welding of aluminum, the behavior
of variable polarity plasma arc is effected by pilot arc. In DCEP time,
through the pilot source and the nozzle, large part of main current
forms free arc not the plasma arc, so double arc happens, the nozzle is
burn away and cathodic cleaning becomes symmetrical. In DCEP time, the
interference of main arc and pilot arc happens sometimes. With new wave
form of the main current, the pilot arc can be turned off after the main
arc is ignited, so the arc interference is avoided and double arc will
not happen.
Key words: Plasma arc Variable polarity Pilot arc
CLC No: TG456.2
Received
20030214, received in revised form 20030428
|