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A Study on the Arc Characteristics and Weld Pool Analysis of GHTAW under the Space Environment

우주 환경에서 GHTAW 아크 특성과 용융지 해석에 관한 연구

  • 이상훈 (한국과학기술원 기계공학과) ;
  • 나석주 (한국과학기술원 기계공학과)
  • Received : 2010.04.05
  • Accepted : 2010.05.04
  • Published : 2010.08.31

Abstract

The purpose of this paper is to understand the behavior of GHTAW process under the space environment with the experimental and numerical analysis. Gas Hollow Tungsten Arc Welding (GHTAW) using a hollow tungsten electrode was adopted, since the ignition and discharge of a conventional GTAW process is not appropriate to the space environment due to low pressure in space. In order to clarify the phenomena of GHTAW under space environment, an investigation of thermal and physical properties of the GHTAW arc plasma was experimentally performed under low pressure conditions. Furthermore, the molten pool behavior and weldment of GHTAW were understood by CFD-based numerical analysis, based on the models of GHTA heat source, arc pressure and electromagnetic force induced by arc plasma, the characteristics of which were obtained by the captured images of a CCD camera.

Keywords

References

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