PSI - Issue 19

Martin Nesládek et al. / Procedia Structural Integrity 19 (2019) 231–237 Nesládek et al./ Structural Integrity Procedia 00 (2019) 000 – 000

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4. Conclusions

Experimental results of the ongoing TMF test campaign were introduced in the paper. Quality of prediction by DOA was verified by them revealing that the method provides better prediction for the tests under higher temperature range, which was 100-600 °C in the case of the tested CrMo steel. Upcoming work will be focused on multiaxial loading under the same temperature ranges that were applied to the uniaxial tests presented here. Thorough metalographic and fractographic analysis is needed to identify differences in damage micro mechanisms participating in the various test conditions applied to specimens. For instance, varying share of oxidation damage might give a clue on answering why there is a bigger prediction error in the case of hot-start tests. Acknowledgements This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Grant Agreements No. 653941 – FLEXTURBINE and No. 764545 – TURBO-REFLEX. Chaboche, J.L., 1989. Constitutive Equations for Cyclic Plasticity and Cyclic Viscoplasticity. International Journal of Plasticity 5(3), 247 – 302. Delprete, C., Sesana, R., 2019. Proposal of a New Low-Cycle Fatigue Life Model for Cast Iron with Room Temperature Calibration Involving Mean Stress and High-Temperature Effects. Journal of Mechanical Engineering Science. DOI: 10.1177/0954406219839089 Hyde, C.J., Sun, W., Hyde, T.H., Saad, A.A., 2012. Thermo-Mechanical Fatigue Testing and Simulation Using a Viscoplasticity Model for a P91 Steel. Computational Materials Science 56, 29-33. Minichmayr, R., Riedler, M., Winter, G., Leitner, H., Eichlseder, W., 2008. Thermo-Mechanical Fatigue Life Assessment of Aluminium Components Uding the Damage Rate Model of Sehitoglu. International Journal of Fatigue 30, 298-304. Morrow, J.D., 1964. Cyclic Plastic Strain Energy and Fatigue of Metals. In Internal Friction, Damping, and Cyclic Plasticity, ed. B. Lazan (West Conshohocken, PA: ASTM International), 45-87. Nagode, M., 2014. Continuous damage parameter calculation under thermo-mechanical random loading. MethodsX 1, 81-89. Nagode, M., Hack, M., Fajdiga, M., 2009. High cycle thermo-mechanical fatigue: Damage operator approach. Fatigue & Fracture of Engineering. Materials & Structures 32, 505-514. Nagode, M., Hack, M., Fajdiga, M., 2009. Low cycle thermo-mechanical fatigue: Damage operator approach. Fatigue & Fracture of Engineering Materials & Structures 33, 149-160. Nagode, M., Šeruga, D., Hack, M., Hansenne, E., 2012. Damage Operator-Based Lifetime Calculation Under Thermomechanical Fatigue and Creep for Application on Uginox F12T EN 1.4512 Exhaust Downpipes. Strain: An International Journal for Experimental Mechanics 48, 198 207. Nesládek, M., Jurenka, J., Bartošák, M., Růžička, M., Lutovinov, M., Papuga, J., Procházka, R., Džugan, J., Měšťánek, P., 2018. Thermo Mechanical Fatigue Analysis of a Steam Turbine Shaft. Acta Polytechnica CTU Proceedings 20. 56-64. Neu, R.W., Sehitoglu, H., 1989. Thermomechanical Fatigue, Oxidation and Creep: Part I. Damage Mechanisms. Metallurgical Transactions 20A. 1755-1767. Neu, R.W., Sehitoglu, H., 1989. Thermomechanical Fatigue, Oxidation and Creep: Part II. Life Prediction. Metallurgical Transactions 20A. 1769-1783. Okazaki, M., Sakaguchi, M., 2008. Thermo-Mechanical Fatigue Failure of Single Crystal Ni-based Superalloy. International Journal of Fatigue 30, 318-323. Ostergren, W.J., 1976. A Damage Function and Associated Failure Equations for Predicting Hold Time and Frequency Effects in Elevated Temperature, Low Cycle Fatigue. Journal of Testing and Evaluation 4(5), 327-339. Sehitoglu, H., Boismier, D.A., 1990. Thermo-Mechanical Fatigue of Mar-M247: Part 2 – Life Prediction. Transactions of the ASME 112, 80-89. Share of renewables in energy consumption in the EU reached 17% in 2016. http://ec.europa.eu/eurostat/documents/2995521/8612324/8 25012018-AP-EN.pdf/9d28caef-1961-4dd1-a901-af18f121fb2d. Accessed:2019-18-04. Skelton, R.P., 1991. Energy Criterion for High Temperature Low Cycle Fatigue Failure. Materials Science and Technology 7(5), 427-440. Smith, K. N., Watson, P., Topper, T. H., 1970. A Stress-Strain Function for the Fatigue of Metals. J Mater, JMLSA 5(4), 767 – 778. References