Journal of Welding and Joining

The Korean Welding and Joining Society (대한용접접합학회)
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Characteristics of Plasma Emission Signals in Fiber Laser Welding of API Steel (IV) - Correlation of Keyhole's Periodic Motion and FFT Analysis Results -

API강재의 파이버레이저 용접시 유기하는 플라즈마의 방사특성 (IV) - 키홀의 주기운동과 FFT분석의 상관성 -

  • Kim, Jong-Do (Division of Marine Engineering, Korea Maritime University) ;
  • Lee, Chang-Je (Graduate School, Korea Maritime University) ;
  • Suh, Jeong (Busan Laser Application Support Center, KIMM)
  • 김종도 (한국해양대학교 기관공학부) ;
  • 이창제 (한국해양대학교 대학원) ;
  • 서정 (한국기계연구원 부산레이저기술지원센터)
  • Received : 2013.06.11
  • Accepted : 2013.08.12
  • Published : 2013.08.31
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Abstract

The effects of laser welding beam quality is very large. However, not an analysing case was found for the difference on the plasma emission signal during laser welding according to the beam quality. Therefore, in this study, we compared and evaluated penetration and signal change according to the beam quality at the a similar wavelength band by using a fiber laser and Nd:YAG laser. In addition, we took high speed videography in order to make sure that FFT analysis reflects the actual motion period of keyhole and found the period of video analysis and FFT mostly matched. As a result, it is expected to secure higher reliability than evaluating signal intensity when appling FFT to monitoring.

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References

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