Advertisement

Structural Integrity Mechanics and Creep Life Prediction of 304HCu Austenitic Stainless Steel Under Multiaxial State of Stress

  • Kanhu Charan SahooEmail author
  • Sunil Goyal
  • P. Parameswaran
  • S. Ravi
  • K. Laha
Conference paper
  • 736 Downloads

Abstract

For increasing the efficiency of fossil power plants, the boiler tube material has to withstand higher temperature and pressure which calls for extensive research for identifying materials having high-temperature strength, good corrosion resistance and adequate mechanical properties. The 304HCu stainless steel 9304HCu SS is one of the candidate materials for boiler tubes employed in advanced ultra-super critical power plants. However, under above circumstances, material will subject to multiaxial state of stress that arises from internal pressure, weld joint, inhomogeneous structure, sudden change in dimension and change in cross section of the tube. Present study aims to introduce multiaxial state of stress through notches of different root radius on creep samples. Notch of different root radii, e.g. 0.25, 0.5, 2.5 was creep tested by keeping notch throat diameter 5 mm. Both plain and notch specimen had creep tested at same stress level at a particular temperature. Notch specimen possesses higher rupture life as compared to plain specimen. Based on these observations, the material is found to be ‘notch strengthening’. Then both SEM and optical micrograph were carried out on the unfailed notch which revealed that cavity density was decreased from notch root towards centre for relatively sharper notch, while random distribution of cavity for shallow notch. FE analysis has been carried out to understand the contribution of different components of stresses, i.e. von-Mises, maximum principal and hydrostatic stresses. Different models given by Cane, Hayhurst and Nix were examined for creep life prediction under multiaxial state of stress. The average hardness near to notch root was more in comparison with regions away from the notch root and shallow notch was found exhibit more hardness in comparison with sharper notch.

Keywords

AUSC Multiaxial creep Finite element analysis Life prediction Hardness measurement 

Notes

Acknowledgements

The authors gratefully acknowledge the encouragement and continuous support received from Dr. A. K. Bhaduri, Director, IGCAR, Kalpakkam. The authors also wish to record their sincere thanks to V. D. Vijayanand, SO/D, IGCAR, Kalpakkam for his help and support during analysis.

References

  1. 1.
    W.D. Nix, Mechanisms and controlling factors in creep fracture. Mater. Sci. Eng. A 103, 103–110 (1988)CrossRefGoogle Scholar
  2. 2.
    K.C. Sahoo, S. Ravi, S. Goyal, P. Parameswaran, K. Laha, Creep ruptures behavior and microscopy analysis of 304 HCu austenitic stainless steel under multiaxial state of stresses at 973 K. Trans. Indian Inst. Met. 69(2), 451–455 (2016)CrossRefGoogle Scholar
  3. 3.
    S. Goyal, K. Laha, K.S. Chandravathi, P. Parameswaran, M.D. Mathew, Finite element analysis of Type IV cracking in 2.25Cr-1Mo steel weld joint based on micro-mechanistic approach. Phil. Mag. 91, 3128–3154 (2011)CrossRefGoogle Scholar
  4. 4.
    T.H. Hyde, W. Sun, A.A. Becker, Failure prediction for multi-material creep test specimens using a steady-state creep rupture stress. Int. J. Mech. Sci. 42, 401–423 (2000)CrossRefzbMATHGoogle Scholar
  5. 5.
    A. Forghani, M. Shahbazi, N. Zobeiry, A. Poursartip, R. Vaziri, An overview of continuum damage models used to simulate intralaminar failure mechanisms in advanced composite materials. in Composites Science and Engineering (A volume in Woodhead Publishing Series) (2015), pp. 151–173Google Scholar
  6. 6.
    P.S. Westera, C. Pickard Rolls-Royce plc, Derby Rolls-Royce plc, Derby the prediction of stress rupture life of notched specimens in theti5331s beta-processed titanium alloyGoogle Scholar
  7. 7.
    W. Li, F. Liao, T. Zhou, H. Askes, Ductile fracture of Q460 steel: effects of stress triaxiality and lode angle. J. Construct. Steel Res. 123, 1–17 (2016)CrossRefGoogle Scholar
  8. 8.
    G.A. Webster, S.R. Holdsworth, M.S. Loveday, K. Nikbin, I.J. Perrin, H. Purper, R.P. Skelton, M.W. Spindler, Fatigue Fract. Eng. Mater. Struct. 27, 319–342 (2004)CrossRefGoogle Scholar
  9. 9.
    D.R. Hayhurst, J. Mech. Phys. Solids 20, 381–390 (1972)CrossRefGoogle Scholar
  10. 10.
    B.J. Cane, in Proceedings of the International Conference on Mechanical behavior of Materials, ed. by K.J. Miller, R.F. Smith (Pergamon Press, Oxford, 1979), pp. 173–182Google Scholar
  11. 11.
    W.D. Nix, J.C. Earthman, G. Eggeler, B. Ilschner, Acta Metall. 37, 1067–1077 (1989)CrossRefGoogle Scholar
  12. 12.
    S. Goyal, K. Laha, Creep life prediction of 9Cr-1Mo steel under multiaxial state of stress. Mater. Sci. Eng. A 615, 348–360 (2014)CrossRefGoogle Scholar
  13. 13.
    S. Goyal, K. Laha, M.D. Mathew, Creep life prediction of modified 9Cr-1Mo steel under multiaxial state of stress. Procedia Eng. 86, 150–157 (2014)CrossRefGoogle Scholar
  14. 14.
    S. Goyal, K. Laha, C.R. Das, S. Panneerselvi, M.D. Mathew, Effect of constraint on creep behavior of 9Cr-1Mo steel. Metall. Mater. Trans. A 45(2), 619–632 (2014)CrossRefGoogle Scholar
  15. 15.
    C.R. Calladine, Proc. R. Soc. Lond. A 309, 363 (1969)CrossRefGoogle Scholar
  16. 16.
    S. Goyal, K. Laha, C.R. Das, S. Panneerselvi, M.D. Mathew, Finite element analysis of effect of triaxial state of stress on creep cavitation and rupture behaviour of 2.25Cr–1Mo steel. Int. J. Mech. Sci. 75, 233–243 (2013)CrossRefGoogle Scholar
  17. 17.
    S. Goyal, K. Laha, A.K. Bhaduri, Response of triaxial state of stress to creep rupture life and ductility of 316 LN austenitic stainless steel. J. Mater. Eng. Perform. 26(2), 752–763 (2017)CrossRefGoogle Scholar
  18. 18.
    Z. Yan, Z. Jie, L.I. Xiaona, Microstructural evolution and change in hardness during creep of NF709 austenitic stainless steel. Acta Metall. Sin. (Engl. Lett.) 24(3), 220–224 (2011)Google Scholar
  19. 19.
    H. Tanaka, M. Murata, F. Abe, H. Irie, Microstructural evolution and change in hardness in type 304H stainless steel during long-term creep. Mater. Sci. Eng. A 319, 788–791 (2001)CrossRefGoogle Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Kanhu Charan Sahoo
    • 1
    Email author
  • Sunil Goyal
    • 1
  • P. Parameswaran
    • 1
  • S. Ravi
    • 1
  • K. Laha
    • 1
  1. 1.Metallurgy and Materials GroupIndira Gandhi Centre for Atomic ResearchKalpakkamIndia

Personalised recommendations