The Effect of Shielding Gas Composition on High Power Laser Welding Characteristics |
Young-Nam Ahn*, Cheolhee Kim* |
Correspondence:
Cheolhee Kim, Email: chkim@kitech.re.kr |
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Abstract |
Laser-gas metal arc hybrid welding has been considered as an alternative process of gas metal arc welding for offshore pipe laying. Fiber delivered high power lasers which enable deep penetration welding were recently developed but high power welding characteristics were not fully understood yet. In this study, the influence of shielding gas composition on welding phenomena in high power laser welding was investigated. Bead shapes, melt ejection and dropping were observed after autogenous laser welding with 100% Ar, Ar-20% CO2, Ar-50% CO2, and 100% CO2 shielding gas. Process parameter window was widest with Ar-50% CO2 shielding gas and the penetration was deepest with 100% CO2 shielding gas. The melt dropping was not observed when Ar-50% CO2 or 100% CO2 shielding gas was supplied. |
Key Words:
High-power laser welding, Shielding gas, Process parameter window, Penetration depth, Melt ejection, Melt dropping |
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