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Effects of C on the Strength and Toughness of FCAW Weld Metal of YS 460 MPa Steels for Ship and Offshore Structures

선박·해양 구조물용 YS 460MPa 강재 FCAW 용접금속의 강도와 인성에 미치는 C의 영향

  • Received : 2014.10.21
  • Accepted : 2014.11.24
  • Published : 2014.12.31

Abstract

This paper has an purpose to study the effect of C on the toughness of YS 460 MPa FCAW weld metal. These effects were evaluated by charpy impact and CTOD test about 4 FCAW weld metal containing various C and Si content in relation to microstructure. Increase of C content was helpful to increase AF volume fraction and reduce PF(G) and FS volume fraction by increasing super cooling rate for ferrite transformation. Also, Increase of C content up to 0.045wt% made the strength and impact toughness higher by increasing AF volume fraction. The weld metal containing higher C content indicated higher CTOD value. It is because the volume fraction of PF(G) and FS, can play a role as crack initiation site, was reduced. Effect of C on the strength and elongation of weld metal was higher with an increase of Si contents.

Keywords

FCAW weld metal;C;Impact toughness;CTOD;Tensile properties

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