• 제목/요약/키워드: GMA-laser hybrid welding

검색결과 17건 처리시간 0.022초

펄스형 Nd:YAG 레이저와 단락이행모드의 직류 GMA 열원을 이용한 하이브리드 용접 공정에 대한 연구 (A Study on the Process of Hybrid Welding Using Pulsed Nd:YAG Laser and Dip-transfer DC GMA Heat Sources)

  • 조원익;나석주
    • Journal of Welding and Joining
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    • 제25권6호
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    • pp.71-77
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    • 2007
  • Until now, many researches on laser-arc hybrid welding processes have been conducted mainly for high power CW laser and high direct current arc to weld the thick steel plates for shipbuilding. Recently, however the usage of thin steel plates, which tend to be deformed easily by thermal energy, is been increasing because of demand of light structure such as car body in the automobile industry. Accordingly, heat sources having relatively low heat input such as pulsed laser, dip-transfer DC GMA and pulsed GMA seem to be applied more increasingly and the study about those heat sources is needed more intensively. Any heat source mentioned above can not stand alone without weld defects at a relatively high welding speed for increasing the welding productivity. This is main reason to apply the hybrid welding process which uses pulsed laser and low-heat-input GMA heat sources simultaneously to weld the thin steel plate. In this study, parameters of pulsed laser and dip-transfer DC GMA welding are studied firstly through preliminary experiments, and then analyzed in the viewpoint of their physical phenomena. Before conducting the hybrid welding, a pulse control technique is developed based on the parallel port communication and Visual C++ 6.0. Owing to development of this technique, interactions of laser and arc pulses can be controlled consistently. Using the pulse control technique, the hybrid welding is conducted and then its interactive welding phenomenon is analyzed.

레이저-GMA 하이브리드 용접에서 유동에 의한 기포 및 기공 형성 해석 (Numerical Simulation of Bubble and Pore Generations by Molten Metal Flow in Laser-GMA Hybrid Welding)

  • 조원익;조정호;조민현;이종봉;나석주
    • Journal of Welding and Joining
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    • 제26권6호
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    • pp.67-73
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    • 2008
  • Three-dimensional transient simulation of laser-GMA hybrid welding involving multiple physical phenomena is conducted neglecting the interaction effect of laser and arc heat sources. To reproduce the bubble and pore formations in welding process, a new bubble model is suggested and added to the established laser and arc welding models comprehending VOF, Gaussian laser and arc heat source, recoil pressure, arc pressure, electromagnetic force, surface tension, multiple reflection and Fresnel reflection models. Based on the models mentioned above, simulations of laser-GMA hybrid butt welding are carried out and besides the molten pool flow, top and back bead formations could be observed. In addition, the laser induced keyhole formation and bubble generation duo to keyhole collapse are investigated. The bubbles are ejected from the molten pool through its top and bottom regions. However, some of those are entrapped by solid-liquid interface and remained as pores. Those bubbles and pores are intensively generated when the absorption of laser power is largely reduced and consequently the full penetration changes to the partial penetration.

LASER ARC HYBRID WELDING

  • Dilthey, Ulrich;Keller, Hanno
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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    • pp.162-168
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    • 2002
  • Hybrid Welding means the coupling of the energy of two different energy sources in a common process zone. This paper describes prospects in laser-arc-hybrid-welding. Different kinds of lasers ($CO_2$ laser and Nd:YAG laser) and arc processes (TIG, Plasma and GMA) are considered.

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디스크 레이저-아크 하이브리드 용접을 이용한 포지션 용접 (Position welding using disk laser-GMA hybrid welding)

  • 임현식;김정학;김철희;김정한
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.1299-1306
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    • 2007
  • The combination of laser beam and electric arc sharing common weld pool has widely been investigated since the late seventies, but it is beginning of the industrial uses. Recently, laser-GMA hybrid welding process showed possibility to overcome the tight gap tolerance with improved productivity. The laser-arc hybrid welding process is inherently complex because it has three kinds of process parameters: arc welding, laser welding and hybrid welding parameters. In this study, the optimum range of the process parameters were determined by high speed image analysis which could unveil the welding phenomena in laser-arc hybrid welding. The laser-arc hybrid welding was applied for position welding from the flat position to the overhead position and the welding characteristics were investigated.

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조선용 강재의 $CO_2$레이저 GMA 하이브리드 용접에서 갭 브리징 능력 향상기술 개발 (Improvement of Gap Bridging Ability in $CO_2$ Laser-GMA Hybrid Welding)

  • 채현병;김철희;김정한;이세헌
    • Journal of Welding and Joining
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    • 제24권5호
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    • pp.49-56
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    • 2006
  • For laser welding in shipbuilding industry, gap bridging capability is one of the most important characteristics to achieve the high productivity and good weld quality. Recently, laser-GMA hybrid welding process is regarded as a distinctive method to overcome the tight gap tolerance with improving the productivity. In this study, the influence of process parameters on the bead formation was experimentally analyzed and the relationship between the process parameters and geometric imperfections was investigated. It was revealed that undercut, excessive weld metal, excessive penetration and incompletely filled groove were the major geometric imperfections. The optimized wire feeding and arc pressure were necessary to ensure the gap bridging ability. The approach to select the process parameters was conducted for butt welding with up to 2mm joint gap, in which the sound weld beads were generated without changing the welding speed.