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To serve in a corrosive environment, a corrosion-resistant rail steel U68CuCr has been developed in China. In the present study, the wear behavior of U68CuCr was investigated and compared with the commonly used rail steel U71MnG by rolling contact friction tests. The results indicate that the mass loss and wear rate of U68CuCr are smaller than those of U71MnG. The wear rates under the dry condition are smaller than those under the water–oil condition. In addition, the formation of oxide and spalling finally achieves the dynamic equilibrium on the surface of two types of rail steels. However, the duration of the lubricative and protective wear debris layer is longer for U68CuCr. Moreover, the worn surface of U68CuCr is relatively flat, while the wear regime of U71MnG is more severe. The amount and volume of the spalling pits of U68CuCr are smaller. Furthermore, the plastic deformation layers are shallower, and the rolling contact fatigue cracks are shorter for U68CuCr because of the finer pearlitic microstructure. The results prove that the U68CuCr rail steel shows good wear-resistant ability, suggesting its superior suitability for application in high-speed railways in a marine environment. [ABSTRACT FROM AUTHOR]

Track–vehicle severe interaction on track with small curve radius results in rail wear and corrugation, and wheel polygonization, which drain considerable resources for rail grinding and wheels re-profiling in metro lines. To reduce the damage caused by track-vehicle severe interaction, the paper analyzes the reasons leading to rail wear and then proposes an architecture of a metro vehicle with independently rotating wheels driven directly by permanent magnet synchronous motors. The architecture is axle guidance, offered by passive linkages, which ensures that all axles are oriented radially, while control strategy was kept as simple as possible, identifying only two basic traction conditions. The concept is first discussed and then validated through a comprehensive set of running dynamics simulation performed with a multibody software to evaluate rail wear and rolling contact fatigue in traction/braking, coasting with different cant deficiency/excess conditions. The multibody dynamics simulation shows that the proposed architecture is virtually capable of avoiding both wear and rolling contact fatigue damages, and achieves the highest possible track friendliness. The concept of the proposed architecture is a track-fiendly metro architecture and could be a good reference for reducing rail-track interaction damages and maintainace cost. [ABSTRACT FROM AUTHOR]