Plasma arc welding of aluminium alloys with reverse polarity in high power ranges

摘要

In the case of aluminium components, plasma arc welding with a reverse-polarity electrode and at high welding currents permits economically viable joining with an excellent weld quality. Because of the extremernthermal load on the torch in the case of an electrode with permanent reverse polarity, a torch system with a corresponding design was developed. Welding tests on various aluminium-magnesium alloys showed that plates with a thickness of 2 to 8 mm can be joined not only using the push-through technique but also using the keyhole process. This resulted in good weld qualities in the chosen high power range at welding currents of 100 to 200 A.