Characteristics of the Keyhole and Energy Absorption during YAG Laser Welding of Al-Li Alloy

Abstract:

In this paper, the keyhole of YAG laser welding 5A90 Al-Li alloy was observed and measured through the high speed camera. The characteristics of the keyhole and the effects of welding parameters were studied. The characteristics of the absorption of laser energy and the susceptivity for heat input in welding 5A90 were given. The results show that in this welding condition, the keyhole of laser welding 5A90 is nearly a taper and the highest temperature area is in the bottom. There are clear effects of heat input on the characteristics, especially the surface radius of keyhole and plasma/vapor in keyhole. Another phenomena is observed that sometime plasma/vapor could disappear in 0.3ms welding time, and this feature will be more remarkable as decrease of heat input. It shows that the absorption of energy is unsteady. It is known that when this instability reaches a certain value, an unsteady weld will be formed.

• Periodical: Advanced Materials Research (Volumes 287-290)
• Pages: 2401-2406
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.287-290.2401
• Online since: July 2011
• Authors: Ai Qin Duan, Shui Li Gong
• Keywords: Heat Input, Keyhole, Laser Welding, Stability

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