Probabilistic Approach for Predicting Degradation Characteristics of Corrosion Fatigue Crack

환경피로균열 열화특성 예측을 위한 확률론적 접근

  • Lee, Taehyun (Department of Reliability Assessment, Korea Institute of Machinery and Materials) ;
  • Yoon, Jae Young (Integrated Safety Assessment Division, Korea Atomic Energy Research Institute) ;
  • Ryu, KyungHa (Department of Reliability Assessment, Korea Institute of Machinery and Materials) ;
  • Park, Jong Won (Department of Reliability Assessment, Korea Institute of Machinery and Materials)
  • 이태현 (한국기계연구원 신뢰성평가연구실) ;
  • 윤재영 (한국원자력연구원 종합안전평가부) ;
  • 류경하 (한국기계연구원 신뢰성평가연구실) ;
  • 박종원 (한국기계연구원 신뢰성평가연구실)
  • Received : 2018.08.30
  • Accepted : 2018.09.19
  • Published : 2018.09.25

Abstract

Purpose: Probabilistic safety analysis was performed to enhance the safety and reliability of nuclear power plants because traditional deterministic approach has limitations in predicting the risk of failure by crack growth. The study introduces a probabilistic approach to establish a basis for probabilistic safety assessment of passive components. Methods: For probabilistic modeling of fatigue crack growth rate (FCGR), various FCGR tests were performed either under constant load amplitude or constant ${\Delta}K$ conditions by using heat treated X-750 at low temperature with adequate cathodic polarization. Bayesian inference was employed to update uncertainties of the FCGR model using additional information obtained from constant ${\Delta}K$ tests. Results: Four steps of Bayesian parameter updating were performed using constant ${\Delta}K$ test results. The standard deviation of the final posterior distribution was decreased by a factor of 10 comparing with that of the prior distribution. Conclusion: The method for developing a probabilistic crack growth model has been designed and demonstrated, in the paper. Alloy X-750 has been used for corrosion fatigue crack growth experiments and modeling. The uncertainties of parameters in the FCGR model were successfully reduced using the Bayesian inference whenever the updating was performed.

Keywords

References

  1. Bond, L. J., Doctor, S. R. and Taylor, T. T. (2008). "Proactive management of materials degradation-a review of principles and programs (PNNL-17779)". Pacific Northwest National Laboratory Richland, WA.
  2. Bond, L. J., Taylor, T. T., Doctor, S. R., Hull, A. B. and Malik, S. N. (2008). "Proactive management of materials degradation for nuclear power plant systems". 2008 International Conference on Prognostics and Health Management, Denver, CO, pp. 1-9.
  3. Doctor, S. R. et al. (2009). "The proactive management of materials degradation (PMMD) and enhanced structural reliability". 20th International Conference on Structural Mechanics in Reactor Technology (SMiRT 20), Finland, Paper 1954.
  4. Rumyantev, A. N. (2006). "Quantile estimate of the uncertainties of probabilistic safety analysis for objects of the nuclear power industry". Atomic Energy, Vol. 101, No. 3, pp. 617-624. https://doi.org/10.1007/s10512-006-0141-1
  5. INTERNATIONAL ATOMIC ENERGY AGENCY (1998). "Component reliability data for use in probabilistic safety assessment". IAEA-TECDOC-478, IAEA, Vienna.
  6. Lee, T. H., Yoon, J. Y., Nam, H. O. and Hwang, I. S. (2014). "A probabilistic environmentally assisted cracking model for steam generator tubes". ASME. J. Pressure Vessel Technol., Vol. 137, No. 2, pp. 021204-021204-7.
  7. Kekkonen, T. and Hänninen, H. (1985). "The effect of heat treatment on the microstructure and corrosion resistance of inconel X-750 alloy". Corrosion Science, Vol. 25, No. 8/9, pp. 789-803. https://doi.org/10.1016/0010-938X(85)90011-3
  8. Mills, W. J., Lebo, M. R. and Kearns, J. J. (1999). "Hydrogen embrittlement, grain boundary segregation, and stress corrosion cracking of alloy X-750 in low and high-temperature water". Metall and Mat Trans A, Vol. 30, No. 6, pp. 1579-1606. https://doi.org/10.1007/s11661-999-0095-8
  9. Symons, D. M. and Thompson, A. W. (1996). "The effect of hydrogen on the fracture of alloy X-750". Metall and Mat Trans A, Vol. 27A, No. 1, pp. 101-110.
  10. Turnbull, A. et al. (1992). "Hydrogen transport in nickel-base alloys". Metallurgical Transactions A, Vol. 23, No. 12, pp. 3231-3244. https://doi.org/10.1007/BF03024530
  11. Grote, K. H. and Antonsson, E. K. (2009). "Springer handbook of mechanical engineering". Springer.
  12. Vander Voort, G. F., Lucas, G. M. and Manilova, E. P. (2004). "Metallography and microstructures of heat-resistant alloys". ASM Handbook, Vol. 9, pp. 824-864.
  13. Hwang, I. S. (1987). "Embrittlement mechanisms of nickel-base alloys in water". Dissertation, Department of Nuclear Engineering, Massachusetts Institute of Technology, Boston.
  14. Was, G. S. and Ballinger, R. G. (1980). "Hydrogen induced cracking under cyclic loading of nickel base alloys used for pwr steam generator tubing". Third Semi-Annual Progress Report, NP4613, Research Project 1166-3, EPRI.
  15. ASTM E647-08 (2008). "Standard test method for measurement of fatigue crack growth rates". ASTM International, West Conshohocken, PA.
  16. Provan, J. W. and Sih, G. (1991). "Probabilistic fracture mechanics and reliability". Martinus Nijhoff Publishers.
  17. Ciavarella, M. (2011). "Crack propagation laws corresponding to a generalized el haddad equation". International Journal of Aerospace and Lightweight Structures, Vol. 1, No. 1, pp. 109-118.