Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Fatigue Characteristics and Compressive Residual Stress of Shot Peened Alloy 600 Under High Temperature

쇼트피닝 가공된 Alloy 600 재료의 고온환경하에서의 잔류응력 및 피로특성

  • Kim, Jong Cheon (Graduate School of NID Fusion Technology, Seoul Nat'l Univ. of Science & Technology) ;
  • Cho, Hong Seok (KEPCO Plant Service & Engineering co., LTD.) ;
  • Cheong, Seong Kyun (Dept. of Mechanical Engineering, Seoul Nat'l Univ. of Science & Technology)
  • 김종천 (서울과학기술대학교 NID 대학원) ;
  • 조홍석 (한전 KPS 주식회사) ;
  • 정성균 (서울과학기술대학교 기계공학과)
  • Received : 2012.07.16
  • Accepted : 2012.09.10
  • Published : 2013.03.01
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Abstract

The compressive residual stress and fatigue behavior of shot peened alloy 600 under a high-temperature environment is investigated in this study. Alloy 600 is used in the main parts of nuclear power plants, and the compressive residual stress induced by the shot peening process is considered to prevent SCC (stress corrosion cracking). To obtain practical results, the fatigue characteristics and compressive residual stress are evaluated under the actual operating temperature of a domestic nuclear power plant, as well as a high-temperature environment. The experimental results show that the peening effects are valid at a high temperature lower than approximately $538^{\circ}C$, which is the threshold temperature. The fatigue life was maintained at temperatures lower than $538^{\circ}C$, and the compressive residual stress at $538^{\circ}C$ was 68.2% of that at room temperature. The present results are expected to be used to obtain basic safety and reliability data.

본 논문에서는 쇼트피닝 가공된 Alloy 600 재료의 고온환경하에서의 압축잔류응력 및 피로거동에 대해 연구하였다. 연구에 사용된 Alloy 600 재료는 원자력발전소에서 사용되는 주요부품 소재이며, 피닝가공으로 형성된 압축잔류응력은 응력부식균열(SCC; Stress Corrosion Cracking)의 발생을 크게 억제하는 것으로 알려져 있다. 현실성 있는 실험결과를 획득하기 위하여 실제 국내 원자력 발전소 주요부품의 사용온도를 포함한 고온 환경에서 피로특성 및 압축잔류응력을 평가하였다. 연구결과 약 $538^{\circ}C$이하에서는 피닝가공 효과가 존재하는 것으로 파악되었다. 피로수명은 $538^{\circ}C$ 까지 유지되는 것으로 분석되었으며, $538^{\circ}C$ 에서의 압축잔류응력은 상온에서의 값에 비하여 68.2%를 유지하였다. 본 연구결과는 원자력발전소의 안전 및 신뢰성 확보에 기초자료로 활용될 것으로 기대된다.

Keywords

References

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