Product Code: ICA12_103

Modeling of Keyhole Formation in Laser and Laser Arc Hybrid Welding Based on CFD Simulations - Invited Presentation
Authors:
Won-Ik Cho, Samsung Electro-Mechanics; -
Muhammad Sohail, Department of Mechanical Engineering, KAIST; -
Suck-Joo Na, Department of Mechanical Engineering, KAIST; Yuseong-gu, Daejeon South Korea
Presented at ICALEO 2012

In the first part of this presentation, the mathematical models of laser welding process, especially the beam path generation in keyhole, are introduced to simulate the high power laser welding processes. The recoil pressure, multiple reflections and Fresnel absorption models are employed to describe the laser keyhole phenomenon. It could be shown that the proper way to treat the multiple reflections is essential for predicting the mechanism of keyhole formation.
In the second part, the laser-arc hybrid welding is represented by merging the aforementioned laser welding models and arc welding models under the assumption that there is no interaction between arc plasma and laser. The flow patterns in weld pool, mixing of alloying elements and weld bead shapes of laser-arc hybrid welding are observed with different welding parameters and compared with experimental results, which reveals that both results are in good agreement with each other. This paper also presents some research subjects to be treated in the future for better understanding of laser and laser-arc hybrid welding.