A study of model for nitrogen permeation in TIG welding of super duplex stainless steel

슈퍼듀플렉스 스테인리스강의 TIG 용접에서 질소 침투 모델에 관한 연구

  • Lee, Jae-Hyoung (Doosan Heavy Industry Nuclear Manufacturing Engineering Team2) ;
  • Jung, Byong-Ho (Dept. of Metallurgical Engineering, Pukyong National University) ;
  • Cho, Sang-Myung (Dept. of Materials System Engineering, Pukyong National University) ;
  • Jun, Jae-Ho (Dept. of Materials System Engineering, Graduate School, Pukyong National University)
  • 이재형 (두산중공업 원자력 생산기술2팀) ;
  • 정병호 (부경대학교 금속공학과) ;
  • 조상명 (부경대학교 신소재시스템공학과) ;
  • 전재호 (부경대학교 신소재시스템공학과 대학원)
  • Received : 2015.05.19
  • Accepted : 2015.06.22
  • Published : 2015.06.30


Superduplex stainless steels are important materials to the oil and gas industry, especially for off-shore production. TIG welding of super duplex stainless steels to obtain the optimal phase balance between austenite and ferrite is mainly achieved by controlling the cooling rate and the weld chemistry. The latter depends on the filler wire chosen and the shielding gas used. If TIG welding of superduplex stainless steels is performed with argon shielding gas only, then nitrogen gets lost from the weld pool, which can result in a ferrite-rich weld metal, with an inferior corrosion resistance than parent metal. In the present study, nitrogen permeation model from the shield gas which gets into the weld metal in DCEN-TIG welding has suggested. This plasma stream model shows characteristics of permeation of nitrogen ions into the molten metal due to the strong physical effect of plasma stream which formed by the arc pressure rather than the permeation of nitrogen ions caused by electric effect.



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