The Weldability of Primer-coated Steel for Shipbuilding by $CO_2$ Laser

조선용 Primer코팅강판의 $CO_2$레이저 용접성

  • 박현준 (한국해양대학교 대학원) ;
  • 김종도 (한국해양대학교 기관시스템공학부) ;
  • 김영식 (한국해양대학교 신소재공학부)
  • Published : 2003.04.23

Abstract

The spatter and porosity could be occurred during $CO_2$ CW laser welding of Primer-coated Steel for Shipbuilding. This study has suggested an alternative idea by examining of weld-defect formation mechanism. The primer-coated plate has caused the spatter, humping bead and porosity and these are main part of the welding defect, attributed to the powerful vaporizing pressure of primer attached on the base metal. The zinc of primer has a boiling point that is the lower temperature than melting point of steel. Zinc va}X)f will build up at the interface between the two sheets and this tends to deteriorate the quality of the weld by ejecting weld material from lap position or leaving porosity. Therefore introducing a small gap clearance in the lap position, the zinc vapor could escape through it and sound weld beads can be acquired. In conclusion, we suggested the occurred and prevented mechanism of weld defects with searching the factor.

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