• Journal of Welding and Joining
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• 제22권1호
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• pp.7-9
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• 2004

• Journal of Welding and Joining
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• 제22권1호
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• pp.18-25
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• 2004

• Journal of Welding and Joining
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• 제33권4호
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• pp.17-23
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• 2015

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% $CO_2$, Ar-50% $CO_2$, and 100% $CO_2$ shielding gas. Process parameter window was widest with Ar-50% $CO_2$ shielding gas and the penetration was deepest with 100% $CO_2$ shielding gas. The melt dropping was not observed when Ar-50% $CO_2$ or 100% $CO_2$ shielding gas was supplied.

• Journal of Welding and Joining
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• 제24권4호
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• pp.22-26
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• 2006

In lap welding of zinc-coated steel, porosity formation is one of most significant weld defects, which is caused by zinc vapor generated between the steel sheets. Various solutions have been proposed in the past years but development of more effective method is a worthwhile subject to be investigated. In this study, autogenous laser welding and laser-TIG hybrid welding was applied to the lap welding of zinc-coated steel without gap, and weld pool behaviors were observed by using high speed camera and the porosity generation mechanism was analyzed. The weld defects were successfully eliminated by laser-TIG hybrid welding. This is because the leading TIG arc partially melted the upper sheet and vaporized/oxidized the coated zinc on the lapped surfaces prior to the trailing laser illuminating the specimen.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2018년도 공동국제학술발표회
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• pp.166-166
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• 2018

• 대한기계학회논문집A
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• 제40권7호
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• pp.667-672
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• 2016

본 연구에서는 SS400에 대해 레이저-아크 하이브리드 용접을 이용하여 맞대기 용접을 실시하였다. 맞대기 용접시 입열에 직접적으로 영향을 미치는 레이저 출력, 용접 전류 및 속도를 변화시켜 실험을 실시하였다. 이를 통해, 결함 없이 원 패스 관통 용접이 이루어지고, 미려한 비드가 형성되는 최적의 맞대기 용접 조건을 도출하였다. 용접부의 기계적 및 조직적 특성을 파악하기 위해 레이저 및 아크 영역에 대해 경도측정 및 미세조직 관찰을 실시하였다. 또한 모재와 용접 시험편의 강도를 비교하기 위해 인장강도 실험을 실시하였으며, 결과적으로 두 시험편의 인장강도 값은 유사하게 나타나는 것을 확인할 수 있었다.

• Journal of Welding and Joining
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• 제24권3호
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• pp.15-21
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• 2006

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2002년도 춘계학술발표대회 개요집
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• pp.258-259
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• 2002

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2004년도 추계학술발표대회 개요집
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• pp.61-63
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• 2004

Recently many research works are going on in the field of application of Laser-Arc hybrid welding for superstructures such as shipstructures. However, the study on heat distribution and welding residual stress of hybrid weld by numerical simulation loaves much to be desired. Therefore in this study an optimized welding condition and numerical simulation for hybrid welding by using Previous numerical analysis which was used to calculate the kent source for hybrid welding has been analyzed.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2006년 추계학술발표대회 개요집
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• pp.216-218
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• 2006

The application of aluminium alloy is increasing for lightweight and high quality transport vehicle. In this study, therefore, it is intended to apply the high speed hybrid welding method for marine grade aluminium alloy(A5083) used for shipbuilding that consists of 3 kW CW Nd:YAG laser and MIG welding process. For this purpose, the characteristics of process parameters(laser & arc combine angle and focal position of hybrid head to specimen) are investigated for hybrid fillet joint. This study also describes determination of heat distribution using finite element model of the T-joint fillet weld using the in-house solver which has been validated for different type of welding problems.