Korean Journal of Materials Research (한국재료학회지)

Materials Research Society of Korea (한국재료학회)
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Effect of Thermal Exposure and Rejuvenation Treatment on Microstructure and Stress Rupture Properties of IN738LC

IN738LC 합금의 열간 노출 및 재생 열처리에 따른 미세조직과 응력 파단 특성의 변화

  • 최백규 (한국기계연구원 내열재료그룹) ;
  • 주동원 (한국기계연구원 내열재료그룹) ;
  • 김인수 (한국기계연구원 내열재료그룹) ;
  • 장중철 (한전전력연구원 발전연구실) ;
  • 조창용 (한전전력연구원 발전연구실)
  • Published : 2001.11.01
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Abstract

Effects of thermal exposure and rejuvenation treatment on the microstructural evolution and the stress-rupture properties of IN738LC have been investigated. The role of precipitates on the stress-rupture properties has been analyzed through microstructural observations. Thermal exposure at $982^{\circ}C$ for 1000 hours gave rise to precipitation of $\sigma$ phase and coarsening of r'. The microstructural degradation with thermal exposure at $982^{\circ}C$ deteriorated stress rupture properties of the alloy. All the existing phases except MC carbides have completely dissolved into the matrix with homogenization treatment at $1200^{\circ}C$ for 2 hours. Microstructure and stress-rupture properties of the thermal exposed specimens have been successfully rejuvenated by the proposed treatment.

Keywords

References

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