Prevention of Back Side Humping in Laser Welding of Al 5J32 Alloy by Using Laser Power Modulation

Al 5J32 합금의 레이저 용접에서 레이저출력 모듈레이션을 이용한 이면 험핑 비드의 안정화

  • 안도창 (LG화학 중대형전지 활성화생산파트) ;
  • 김철희 (한국생산기술연구원 용접.접합연구그룹) ;
  • 김재도 (인하대학교 기계공학부)
  • Received : 2011.07.04
  • Accepted : 2011.08.22
  • Published : 2011.08.31


In the 5xxx series Al-Mg alloy, magnesium addition can increase the strength of aluminum alloy by solid solution strengthening but it has a relatively low melting and boiling temperature. During full -penetration laser welding of the Al-Mg alloys, its low boiling point and high vapor pressure brings about the spiky humping bead on the bottom side. Under back-side shielding, the spiking of back bead can be reduced but it restraints the process flexibility. In this study, a square pulse waveform modulation was employed to stabilize keyhole and back bead surface without back-side shielding. By using an experimental design, the bead shapes were evaluated for various process parameters such as the focal position, welding velocity and waveform parameters and the smooth back bead shape could be achieved.


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