13th International Conference on Fracture June 16–21, 2013, Beijing, China -10- 8. Summary Development of a TMF test facility has been demonstrated and a simulation technique has been developed to predict TMF crack growth in test specimens based on growth laws determined from isothermal tests. The simulation technique is a general one which can be applied to complex loading scenarios applied to real components. Only a small number of TMF test results are so far available but initial comparisons between test and simulation are encouraging. Additional test results and simulation comparisons are required to further verify the simulation approach. Acknowledgements The authors would like to acknowledge the financial support of the UK Technology Strategy Board (TSB) and the Ministry of Defence (MoD) project called “Developing Improved Service Propagation Lives in Arduous Cyclic Environments (TP/8/MAT/6/I/Q1525K)” and Rolls-Royce plc. References [1] British Standards Institution, “Metallic materials – verification of static uniaxial testing machines. Part 1: Tension/compression testing machines – Verification and calibration of the force-measuring system”, BS EN ISO 7500-1:2004. [2] “A procedure for the measurement of machine alignment in axial testing”, VAMAS Report No. 42, ISSN 1016-2186, February 2003. [3] F.J. Horton, “Crack propagation in corner-crack test pieces – test procedure”, Rolls-Royce plc Materials and Mechanical Methods MMM31002, Issue 1, 15 May 1995. [4] ASTM E647-08e1, “Standard test method for measurement of fatigue crack growth rates”. [5] European Commission Directorate-General Joint Research Centre – Institute for Energy, “Validated Code-of-Practice for Strain Controlled Thermo-mechanical Fatigue Testing”, EUR 22281 EN. [6] J. Gayda, T.P. Gabb, R.V. Miner, Fatigue crack propagation of nickel-base superalloys at 650°C, NASA Technical Memorandum 87150, 1985. [7] T. Nicholas, T. Weerasooriya, Hold-time effects in elevated temperature fatigue crack propagation, in: Fracture Mechanics: Seventeenth Volume, ASTM STP 905, J. H. Underwood, et al, Eds., American Society for Testing and Materials, Philadelphia, 1986, p. 155 [8] T. Nicholas, M.L. Heil, G.K. Haritos, Predicting crack growth under thermo-mechanical cycling, Int. J. Fracture, 41 (1989) 157-176. [9] C. Moura Branco, A. Sousa e Brito, J. Byrne, Life extension methodology based on creep-fatigue models, RTO AVT Workshop, Corfu, Greece, Oct 5-6 1998, in: “Qualification of Life Extension Schemes for Engine Components”, ISBN 92-837-1012-6. [10]C. Timbrell, R. Chandwani, D. MacLachlan, S. Williams, A time dependent crack growth law for high temperature conditions, NAFEMS European Conference: Multiphysics Simulation, Frankfurt, Germany, Oct 16-17 2012. [11] Zencrack 7.8-1, Zentech International Limited, UK. [12]D.A. Jablonski, J.V. Carisella, R.M. Pelloux, Fatigue crack propagation at elevated temperatures in solid solution strengthened superalloys, Metallurgical Transactions A, 8A (1977) 1893-1900. [13]K. Makhlouf, J.W. Jones, Effects of temperature and frequency on fatigue crack growth in 18% Cr ferritic stainless steel, Int. J. Fatigue, 15 No. 3 (1993) 163–171.
RkJQdWJsaXNoZXIy MjM0NDE=