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Thermodynamic Modeling of Ni-Cr-Nb-C System for Analysis of Fracture Behavior of Heat-resistant Casting Alloys (IN-657)

내열 주조 합금 (IN-657) 파괴 거동 해석을 위한 Ni-Cr-Nb-C 시스템 열역학 모델링

  • 김동응 (한국생산기술연구원 뿌리기술연구소 스마트액상성형연구부문)
  • Received : 2021.08.19
  • Accepted : 2021.09.14
  • Published : 2021.10.30

Abstract

Computational thermodynamics for various alloy systems is well known as the CALPHAD technique. Gibbs energy model parameters for each phase are obtained from experimentally measured thermodynamic properties and are mainly used to predict areas not experimentally measured and to analyze experimental results thermodynamically. In this study, the thermodynamic modeling of the Ni-Cr-Nb-C quaternary system is conducted for a thermodynamic analysis of the phenomena by which heat-resistant cast alloys (IN-657) are destroyed in certain areas after long-term use. The stable phases in the system according to the Cr content, phase fraction depending on the temperature, and long-range ordering parameters for the Ni2Cr phase are calculated and compared to results obtained experimentally. The calculated thermodynamic properties suitably explain the experimentally reported fracture temperature range and the results of stable phases formed in the fractured areas. Thermodynamic modeling through the CALPHD method is expected to be useful for analyzing and predicting the thermodynamic behaviors of various cast alloys.

다양한 합금계에 대한 계산열역학은 CALPHAD 기법으로 잘 알려져있다. 실험적으로 측정된 열역학 특성들을 활용하여 각 상에 대한 Gibbs 에너지 모델 파라미터들을 구하여, 주로 실험적으로 측정되지 못한 영역에 대한 예측이나 실험 결과에 대한 열역학 해석에 활용되고 있다. 본 연구에서는 내열 주조 합금 (IN-657)이 장시간 사용 후에 일정 영역에서 파괴되는 현상의 열역학적 해석을 위해 Ni-Cr-Nb-C 사원계 시스템의 열역학 모델링을 수행하였고, Cr 함량에 따른 시스템의 안정상, 온도에 따른 상분율 및 Ni2Cr상의 long range ordering 파라미터를 계산하였고 실험결과와 비교하였다. 계산된 열역학 물성들은 실험으로 보고된 파괴온도 영역 및 해당 영역에서 생성된 안정상에 대한 결과를 잘 설명한다. CALPHAD 기법을 통한 열역학 모델링은 다양한 주조 합금의 열역학적 거동을 해석하고 예측하는데 유용하게 사용될 수 있을 것으로 기대된다.

Keywords

Acknowledgement

본 연구는 미래창조과학부에서 추진하는 민간수탁활성화지원사업의 지원을 받아 수행되었습니다.

References

  1. Heat and Corrosion Resistant Castings: their engineering properties and applications, Nickel Development Institute, (2002).
  2. I. Park, et al., Mechanism of Failure of UNS R20501 High Temperature Tube Support Pipes After 10 Years of Service, in CORROSION 2018 (2018).
  3. Dinsdale, A.T., SGTE data for pure elements. Calphad, 15(4) (1991) 317. https://doi.org/10.1016/0364-5916(91)90030-N
  4. Bragg, W.L. and E.J. Williams, Proceedings of the Royal Society of London Series a-Mathematical and Physical Sciences, 151(A874) (1935) 0540.
  5. Redlich, O. and A.T. Kister, Industrial and Engineering Chemistry, 40(2) (1948) 345. https://doi.org/10.1021/ie50458a036
  6. Kubaschewski, O., C.B. Alcock, and P. Spencer, Materials thermochemistry. revised. Pergamon Press Ltd, Headington Hill Hall, Oxford OX 3 0 BW, UK, 1993. 363, 1993.
  7. B.J. Lee and S.K. Kim, "Atomic simulation and phase field model", Hongreung Publishing Company, Seoul (2016).
  8. Gustafson, P., Calphad, 1988. 12(3) (1988) 277. https://doi.org/10.1016/0364-5916(88)90008-9
  9. B.J. Lee, Calphad, 16(2) (1992) 121. https://doi.org/10.1016/0364-5916(92)90002-F
  10. K.S Chan, Y.M. Pan, and Y.D. Lee, Metallurgical and Materials Transactions A, 37(7) (2006) 2039. https://doi.org/10.1007/BF02586124
  11. Bolcavage, A. and U.R. Kattner, Journal of Phase Equilibria, 17(2) (1996) 92. https://doi.org/10.1007/BF02665782
  12. Singleton, M. and P. Nash, Bulletin of Alloy Phase Diagrams, 10(2) (1989) 121. https://doi.org/10.1007/BF02881419
  13. Gabriel, A., C. Chatillon and I. Ansara, High temperature science, 25 (1988) 17.
  14. Costa Neto, J.G., et al., Calphad, 17(3) (1993) 219. https://doi.org/10.1016/0364-5916(93)90001-R
  15. Peng, Y., et al., Calphad, 53 (2016) 10. https://doi.org/10.1016/j.calphad.2016.02.004
  16. Andersson, J.-O., Calphad, 11(3) (1987) 271. https://doi.org/10.1016/0364-5916(87)90045-9
  17. Chase Jr, M.W., J. Phys. Chem. Ref. Data, Monograph, 9 (1998).
  18. Huang, W., Materials Science and Technology, 6(8) (1990) 687. https://doi.org/10.1179/026708390790193709
  19. Du, Y., et al., Calphad, 29(2) (2005) 140. https://doi.org/10.1016/j.calphad.2005.06.001
  20. Kodentsov, A., et al., Vestnik Moskovskogo Universiteta, Seriya 2. Khimiya, 1986. 27(3) (1986) 275.
  21. Leonovich, B., Steel in Translation, 41(5) (2011) 371. https://doi.org/10.3103/S096709121105010X
  22. Bragg, W.L. and E.J. Williams, Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, 145(855) (1934) 699.
  23. Vintaykin, Y.Z. and G.G. Urushadze, Fiz. Met. Metalloved., 27(5) (1969) 895.