Investigation on Welding Phenomenon for Aluminum Alloy by Superposition of Pulsed YAG Laser and Diode Laser

Abstract

A pulsed Nd:YAG laser and a continuous diode laser were spatially superposed for higher absorption of laser beam to aluminum alloy. 12-20% increase in the bead width and 15-30% increase in the weld depth could be obtained by the superposition of continuous diode laser and pulsed Nd:YAG laser. Moreover, the unsteady thermal analysis with a key-hole effect indicated that the temperature of specimen surface with a continuous diode laser could be kept approximately 300K higher than that without a continuous diode laser. Therefore, it was clarified that the bead width and depth would increase greatly due to higher absorption of Nd:YAG laser to aluminum alloy by the superposition of a continuous diode laser.