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High Temperature Tensile Strength and Fatigue Life Characteristics for Reduced Activation Ferritic Steel (JLF-1) by TIG Welding

TIG 용접한 저방사화 페라이트강 (JLF-1)의 고온강도 및 피로수명특성

  • 윤한기 (동의대학교 기계공학과) ;
  • 이상필 (동의대학교 기계공학과) ;
  • 김사웅 (동의대학교 대학원 기계공학과) ;
  • Published : 2003.09.01

Abstract

The fatigue life and tensile strength of JLF-1 steel (Fe-9Cr-2W-V-Ta) and its TIG weldment were investigated at the room temperature and $400^{\circ}C$. Four kinds of test specimens, which associated with the rolling direction and the TIG welding direction were machined. The base metal of JLF-1 steel represented almost anisotropy in the tensile properties for the rolling direction. And the base metal of JLF-1 steel showed lower strength than that of TIG weldment. Also, the strength of all materials entirely decreased in accordance with elevating test temperature. Moreover, the fatigue limit of weld metal was largely increase than that of base metal at both temperatures. The fatigue limit of JLF-1 steel decreased in accordance with elevating test temperature. The fatigue limit of JLF-1 steel decreased in accordance with elevating test temperature. The SEM fractography of tensile test specimen showed conspicuous cleavage fracture of a radial shape. In case of fatigue life test specimen, there were so many striations at crack initiation region, and dimple was observed at final fracture region as a ductile fracture mode.

Keywords

Reduced Activation Ferritic Steel;TIG Welding;High Temperature Strength;High Temperature Fatigue Life

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