Prediction of Long-Term Stress Intensity Limit of High-Temperature Creep Structures

고온 크리프 구조물의 장시간 한계응력강도 예측

  • 김우곤 (한국원자력연구소 원자력재료기술개발부) ;
  • 류우석 (한국원자력연구소 원자력재료기술개발부) ;
  • 김현희 (중아대학교 기계공학과)
  • Published : 2003.04.23

Abstract

In order to predict stress intensity limit of high-temperature creep structures, creep work-time equation, defined as $W_ct^P=B$, was used, and the results of the equation were compared with isochronous stress-strain curve (ISSC) ones of ASME BPV NH Code. For this purpose, the creep strain tests with. time variations for commercial type 316 stainless steel were conducted with different stresses; 160 MPa, 150 MPa, 145 MPa, 140 MPa and 135 MPa at $593^{\circ}C$. The results of log $W_c$ and log t plots showed a good linear relation up to $10^5$ hr. The constants p, B and stress intensity limit values showed comparatively good agreement to those of ASME NH ISSC. It is believed that the relation can be simply obtained with only several short-term 1% strain data without ISSC which can be obtained by long-term creep data.

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