Transactions of the Korean Society of Pressure Vessels and Piping (한국압력기기공학회 논문집)

Korean Society of Pressure Vessels and Piping (한국압력기기공학회)
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Effects of the Heat Treatment on the Microstructure and Mechanical Properties of the Diffusion-Bonded Ferritic/Martensitic Steel

확산접합된 페라이트/마르텐사이트강의 미세조직 및 기계적 특성에 미치는 열처리 효과

  • 사인진 (한국원자력연구원 수소생산원자로기술개발부) ;
  • 김성환 (한국과학기술원 원자력및양자공학과) ;
  • 홍성훈 (한국과학기술원 원자력및양자공학과) ;
  • 장창희 (한국과학기술원 원자력및양자공학과)
  • Received : 2015.05.01
  • Accepted : 2015.06.29
  • Published : 2015.06.30
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Abstract

As a measure of improving the mechanical properties of a diffusion bonded joint of a ferritic/martensitic steel (FMS), the post-bonding heat treatment (PBHT) is applied. In the temperature range of normalizing condition ($950-1,050^{\circ}C$), diffusion bonding is employed with compressive stress (6 MPa). Due to the martensite structure distributed in the matrix, Vicker's hardness values of the as-bonded are much higher than those of the as-received. Through the PBHT for 1 h at $720^{\circ}C$, hardness values are recovered to as low as those of the as-received condition. Also, tensile properties of PBHT are similar to those of the as-received at up to the test temperature of $550^{\circ}C$, when the diffusion bonding is carried out over $1,000^{\circ}C$. Based on the creep-rupture testing performed at $650^{\circ}C$ in air environment, the joint efficiency of the PBHTed specimens is about 80% in, which is higher than that of the as-bonded specimens.

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References

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