Product Code: ICA11_M205

Welding Characteristics of Aluminum Alloy by Pulsed Nd:YAG Laser with Pre- and Post-Irradiation of Superposed Continuous Diode Laser
Authors:
Shin-ichi Nakashiba, Kataoka Corporation; Yokohama Japan
Yasuhiro Okamoto, Okayama University; Okayama Japan
Tomokazu Sakagawa, Kataoka Corporation; Yokohama Japan
Kazuya Miura, Okayama University; Okayama Japan
Akira Okada, Okayama University; Okayama Japan
Yoshiyuki Uno, Okayama University; Okayama Japan
Presented at ICALEO 2011

Authors developed the high-performance micro-welding of aluminum alloy, in which the superposition of continuous diode laser of wavelength 808nm and pulsed Nd:YAG laser of wavelength 1064nm could perform the high-processing speed, the deeper penetration depth and the wider bead width. However, the penetration depth at the beginning of laser scanning was insufficient, and the evaluation of cracks was not cleared yet. Therefore, in this study, the effects of pre- and post-heating with continuous diode laser on welding phenomena were experimentally and numerically investigated. The combination of continuous diode laser and pre-heating pulse of Nd:YAG laser without melting of specimen surface could keep the high surface temperature, which led to the stable deeper penetration depth and wider bead width with smooth surface integrity even at the beginning of laser scanning. Moreover, it was confirmed that the superposition of continuous diode laser was effective to improve a welding quality of aluminum alloy, since the superposition of continuous diode laser prevented rapid heating and cooling of aluminum alloy. The post-heating with continuous diode laser kept the gentle temperature gradient at the laser spot, and the generation of crack could be decreased by appropriate power and irradiation time of continuous diode laser.