Weldability of $620^{\circ}C$ Grade High Cr Ferrite Cast Steel for Turbine Casing

$620^{\circ}C$급 터빈 케이싱용 고Cr 페라이트강의 용접성

  • 변지철 (부경대학교 신소재공학부) ;
  • 방국수 (부경대학교 신소재공학부) ;
  • 권희경 (두산중공업(주) 기술연구원) ;
  • 지병하 (두산중공업(주) 기술연구원)
  • Published : 2006.05.01

Abstract

Weldability of high Cr ferritic steel for $620^{\circ}C$ grade turbin casing were investigated. The effect of carbon content on the cold and hot cracking susceptibility and HAZ softening was determined. The cast steel with higher carbon content showed higher HAZ hardness because of the dissolution of cabonitrides during welding thermal cycle. Moreover, it showed higher solidification cracking sensitivity because of the little S-ferrite formation in weld metal. Both steels showed HAZ softening at $900^{\circ}C$ peak temperature after PWHT.

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