A Study on Characteristics of Plasma Emission Signals with Welding Conditions in CO2 Laser

CO2 레이저용접시 용접조건에 따른 플라즈마 방사신호의 특성연구

  • 김종도 (한국해양대학교 기관시스템공학부) ;
  • 이창제 (한국해양대학교 대학원)
  • Published : 2009.11.01


Today, implementation of the defect detection in laser welding has been researched for a long time, but most studies have been made around thin plate within $1{\sim}3mm^t$. Therefore, this study was measured and analyzed light emission signals of the induced plasma in $CO_2$ laser lap welding of $6mm^t$ Zn primer-coated steel, and based on this analysis, research made an investigation into possibility of monitoring in thick plate welding. It was been analyzing the measured signals by RMS and FFT processing, as a results, we were able to confirm definite difference of two signals between humping bead and sound bead. Thus, possibility of real time monitoring in $CO_2$ laser lap welding verified experimentally.


Laser Welding;Zn-Coated Steel;Lap Welding;RMS Signal;FFT Processing


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  2. Laser Welding of Zn-Coated Steel vol.34, pp.10, 2010,