Trains often operate as a shuttle service. When a train arrives at the terminal station, its direction of travel is reversed, and therefore so is the rolling direction of the wheels. It is therefore important to investigate how the crack propagation, and wear on the wheel tread are changed by reversing the rolling direction. In this study, twin disc wear-fatigue tests were carried out under various conditions to study the effect on the behaviour of rolling contact fatigue (RCF) cracks and wear. Also, finite element analyses (FEA) were performed in order to clarify the results of these tests. In the lubricated condition, the cumulative wear tended to increase when the rolling direction of the wheel specimen was reversed if the slip ratio was 1%. On the other hand, in the dry condition, there was almost no change in the wear before and after reversing. FEA suggested that, when the wheel specimen was reversed, lubricant was trapped in the RCF crack and the friction coefficient between the crack faces was reduced, leading to shear mode crack growth and increased the fatigue wear.
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