Pulsed tungsten inert gas welding - with pulsed current decay to avoid end crater defects

摘要

A constant distance is maintained between the electrode and the workpiece and the current alternates between a higher pulse current and a lower base current. Relative movement takes place between the welding head and the workpiece, and the current is slowly reduced at the end of the joint. The relative speed of the welding head and the workpiece is reduced during the current decay; alternatively it may be zero. The process avoids the formation of an end crater and porosity by a simple technique.