PSI - Issue 4

Hans-Jakob Schindler / Procedia Structural Integrity 4 (2017) 48–55 Author name / Structural Integrity Procedia 00 (2017) 000 – 000

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Stresses due to the press-fit of the wheels can also be considered as residual stresses. They represent another important influencing factor that affects the fatigue life. Since these stresses are tensile near the surface, it is advisable to strive for a press-fit as weak as possible. Besides residual stresses, there are other influencing factors that play an important role in the safe life analysis of a railway axle, including load-sequence effects leading to plasticity-induced crack closure, or environmental effects leading to increased remote closure. Both affect the effective threshold value. The corresponding effects were not considered in the present investigation, but they are likely to contribute to the uncertainty of safe life predictions.

Acknowledgements

The author wishes to thank Dr. Ernst Moor, MOOR SchadensManagement GmbH, Windisch, Switzerland, for many fruitful discussions on fatigue and safety of railway axles, and Thomas Grossenbacher, SBB, Bern, Switzerland, for making this investigation possible.

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