Dynamic Analysis of Metal Transfer using VOF Method in GMAW (II) - Short Circuit Transfer Mode -

VOF 방법을 이용한 GMA 용접의 금속 이행에 관한 동적 해석 (II) - 단락 이행 모드의 해석 -

  • 최상균 (한국과학기술원, 기계공학과) ;
  • 고성훈 (한국과학기술원, 기계공학과) ;
  • 유중돈 (한국과학기술원, 기계공학과) ;
  • 김희진 (생산기술연구원)
  • Published : 1997.06.01

Abstract

Dynamic characteristics of the short circuit mode are investigated using the Volume of Fluid (VOF) method. When the initial molten drop volume, contact area and wire feed rate are given, rate change of the molten bridge profiles, pressure and velocity distributions are predicted. The electromagnetic force with proper boundary conditions are included in the formulation to consider the effects of welding current. It is found that the molten metal is transferred to the weld pool mainly due to the pressure difference caused by the curvatures in the initial stage, and electromagnetic force becomes dominant factor in the final stage of short circuit transfer. Necking occurs at the contact position between the molten drop and weld pool, and the initial molten drop volume and welding current have significant effects on break-up time.

Keywords

References

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