Abstract
We propose a new method that uses a plume produced by a pulsed laser for triggering arc discharge in a tungsten inert gas (TIG) arc welding system. When a pulsed laser is focused onto an aluminum alloy plate (anode) placed under a tungsten rod (cathode), an arc is discharged between the electrodes through a plume generated from the laser focusing spot. The disadvantages of the conventional triggering methods that require high-frequency generation, high-voltage pulse, or may cause sticking of the rod to the plate are removed in the new method. We also investigate the minimum laser energy required for triggering, and find that laser irradiation in Ar gas is preferable for triggering arc discharge in the TIG arc welding system.
