스테인리스강 용접부의 기계적 성질에 미치는 후열처리의 영향

The influence of post weld heat treatment on mechanical properties of stainless steel weldment

  • 한종만 (대우중공업(주), 선박해양기술연구소) ;
  • 한기형 (대우중공업(주), 선박해양기술연구소) ;
  • 이은배 (대우중공업(주), 선박해양기술연구소) ;
  • 허만주 (대우중공업(주), 선박해양기술연구소) ;
  • 한용섭 (대우중공업(주), 선박해양기술연구소)
  • 발행 : 1996.06.01

초록

In this paper the influence of postweld heat treatment on mechanical properties of SMAW and FCAW stainless steel weldments was examined and the obtained results are as follows ; (1) The amount of $\delta$-ferrite formed by SMAW and FCAW process decreased with increasing holding temperature and time in post weld heat treatment(PWHT), and it was found that the reduced ferrite was transformed into sigma phase after $800^{circ}C{\times}50hr$ PWHT. This sigma phase, even though it was very small, resulted in brittleness of dissimilar weldment between carbon steel and stainless steel in bending test, however in similar weldment between stainless steel and stainless steel was not occured. (2) The chemical composition of sigma phase was measured to 28-30%Cr, 7-9%Mo, 4-6Ni in 316L weldment, and also 35-37%Cr, 0.9-1.0Mo, 6-8%Ni in 309L weldment by EDS analysis.

키워드

참고문헌

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