A model for creep life prediction of thin tube using strain energy density as a function of stress triaxiality under quasi-static loading employing elastic-creep & elastic-plastic-creep deformation

Abstract

This paper demonstrates the application of a new multiaxial creep damage model developed by authors using stress traixiality to predict the failure time of a component made of 0.5%Cr-0.5%Mo-0.25%V low alloy steel. The model employs strain energy density and assumes that the uniaxial strain energy density of a component can be easily calculated and can be converted to multi-axial strain energy density by multiplying it to a function of stress trixiality which is a ratio of mean stress to equivalent stress. For comparison, an elastic-creep and elastic-plastic-creep finite element analysis (FEA) is performed to get multi-axial strain energy density of the component which is compared with the calculated strain energy density for both cases. The verification and application of the model are demonstrated by applying it to thin tube for which the experimental data are available. The predicted failure times by the model are compared with the experimental results. The results show that the proposed model is capable of predicting failure times of the component made of the above-mentioned material with an accuracy of 4.0%.

Keywords

elastic-creep / elastic-plastic-creep / stress triaxiality / life prediction / pressure vessels / finite element analysis (FEA)

References

[1] Ng L, Zarrabi K. A multiaxial creep damage hypothesis and its application to predict life of 2.25%Cr-1%Mo (Bridgman) notched bars. In: Proceedings of the ICMEM, Int Conf Mech Eng and Mechanics (Nanjing, China). USA: Science Press, 2005, 127-130

[2] Ng L, Zarrabi K. Creep life prediction of 0.5%Cr-0.25%V thick walled cylinder using new multiaxial approach. In: Proceedings of the IMECE, CD-ROM, ASME, Int Mech Cong and Expo, Orlando, Florida, USA, 2005

[3] Zarrabi K, Ng L. A novel and simple approach for predicting creep life based on tertiary creep behaviour. ASME Journal of Pressure Vessels Technology, 2008, 130: 041201 (10 pages)

[4] Ng L, Zarrabi K. A creep damage model for predicting failure on multi-material-cross-weld components. In: Proceedings of the Structural Integrity & Failure Conference, CD-ROM, Sydney, Australia, <day>27-29</day>, <month>September</month>, 2006

[5] Zarrabi K, Ng L. On integrity assessment of axisymmetric components operating within creep regime. The Chinese Journal of Mechanical Engineering, 2006, 19(4): 492-495

[6] Zarrabi K, Ng L. Energy-based paradigm for predicting creep damage/life of axisymmetric components. International Journal of Science and Technology - Scientia Iranica - Transactions on Mechanical and Civil Engineering, 2007, 14(5): 450-457

[7] Ng L, Zarrabi K. On creep failure of notched bars. Engineering Failure Analysis, 2008, 15(6): 774-786

[8] Mahmood T, Jelwan J, Zarrabi K. Comparison of various life prediction models under quasi-static loading and non-linear material behaviour. International Journal of Reliability and Safety of Engineering Systems and Structures, Part D, IJRSESS, 2011, 1(1): 43-51

[9] High temperature design data for ferritic pressure vessel steels. The Creep of Steel Working Party of the Institution of Mechanical Engineers, London, 1980

[10] RCC-MR. Design and construction rules for mechanical components of FBR nuclear islands. Section 1, Subsection Z: Technical Appendix A3, AFCEN, Paris, 1985

[11] Norton F H. The Creep of Steel at High Temperatures. London: McGraw-Hill, 1929

[12] Brown R J. Creep rupture testing of tubular model. In: Gooch D J, How I M, eds. Techniques for Multiaxial Creep Testing. London: Elsevier Applied Science, 1985, 311-332

[13] Assessment Procedure for the High Temperature Response of Structures, R5. Berkeley Technology Centre, Nuclear Electric plc, <month>July</month>1995 (Issue 2)

[14] ANSYS Release 13, ANSYS, Inc, USA, <month>May</month>2010

[15] Wilshire B, Scharning P J. Extrapolation of creep life data for 1Cr-0.5Mo steel. International Journal of Pressure Vessels and Piping, 2008, 85(10): 739-743

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