PSI - Issue 13

H. Soares et al. / Procedia Structural Integrity 13 (2018) 1786–1791 Soares et al. / Structural Integrity Procedia 00 (2018) 000 – 000

1791

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4. Conclusions

In this work it was evaluated the mechanical behavior of a material with two different heat treatments obtained from a train wheel subjected to uniaxial and multiaxial loading conditions. Results show that a constant stress scale parameter is unsuitable to estimate fatigue strength under multiaxial loadings. Stress level, loading path type and heat treatments have a strong influence on the stress scale factor variation, therefore to estimate fatigue strength under multiaxial loading conditions these aspects need to be considered. The damage scale equations were obtained for Case 2 and Case 3 and can be used to estimate the fatigue strength of a material. Also, a critical plane study was carried out for both applied loading paths. The results show that the SWT and Liu I criteria have an improved performance comparatively to the other criteria evaluated; based on the obtained results the heat treatment does not have a significative effect on the critical plane orientations for non-proportional loadings.

Acknowledgements

This work was supported by FCT, through IDMEC, under LAETA, project UID/EMS/50022/2013. Financial support from Portuguese Fundação para a Ciência e Tecnologia (FCT) is acknowledged through Project PTDC/EMS PRO/5760/2014.

References

Anes, V., Reis, L., Li, B., Fonte, M., De Freitas, M. (2014). New approach for analysis of complex multiaxial loading paths. International Journal of Fatigue, 62, 21–33. Anes, Vítor, de Freitas, M., Reis, L. (2017). The damage scale concept and the critical plane approach. Fatigue & Fracture of Engineering Materials & Structures, 40(8), 1240–1250. Anes, Vitor, Reis, L., Li, B., De Freitas, M. (2014). New cycle counting method for multiaxial fatigue. International Journal of Fatigue, 67, 78–94. Bathias, C., 1999. There is no infinite fatigue life in metallic materials. Fatigue and fracture of engineering materials and structures, 22, 559-566. Fatemi, A., Socie, D. F. (1988). A critical plane approach to multiaxial fatigue damage including out-of-phase loading. Fatigue & Fracture of Engineering Materials & Structures, 11(3), 149–165. Zucarelli et al., Experimental characterization of the mechanical properties of railway wheels manufactured using class C material, Theoretical and Applied Fracture Mechanics Volume 85, Part A, October 2016, Pages 134-139 (2016). Zucarelli, Tiago Alegretti, Mechanical and metallurgical characterization of railway wheels and analysis of critical working temperatures, in: Aeronautical Engineering and Mechanics. Materials and Manufacturing Processes, Technological Institute of Aeronautics, São José dos Campos – SP, 2013 (in Portuguese).