Experimental Study On Corrugated Wear Of Sliding Surfaces Caused By Friction-Induced Vibration

Rail corrugation, an appearance of regular peaks and troughs on the running surface of the rail, has been puzzling the development of the railway industry all over the world. Many researchers have carried out a large number of extensive studies on this issue. Because the occurrence and the development of the rail corrugation involve a very complex relationship between the dynamics, tribology and materials science and many other disciplines, the problem has not been completely solved up to date.In this dissertation, the contact stress between the wheel and the rail is simulated using a pin-disc friction test device to study the problem of corrugated wear between the wheel and the rail. Friction-induced vibration signals during testing and profiles of worn scars after testing are measured to study the relationships between the friction-induced vibration and the corrugated wear of sliding surfaces. In addition, SEM observation is performed to analyze the morphology of the friction surfaces, and the material factors on corrugation are studied experimentally. The study leads to the following conclusions:(1) Rail corrugation is related to friction-induced vibration, and the fluctuation of friction power caused by friction vibration is a main causes of rail corrugation.(2)The wavelength of corrugated wear is approximate to sliding speed multiplied by the period time of the friction-induced vibration, and is almost not changed when the load is changed. The increase of load can aggravate occurrence of rail corrugation since a grater load can result in severer wear.(3) The factors affecting rail corrugation include dynamics, contact mechanics, tribology and so on, and the plastic deformation of materials caused by a high temperature of the friction surface has an important influence on rail corrugation.(4) Under the differential conditions, the increase of the cycle number has a little bit effect on the rail corrugation wavelength after the rail corrugation occurs.(5) The friction process will produce a large amount of wear debris, which have an important impact on friction. The wear debris may not only lead to abrasive wear, but also cause friction squeal if there is a lot of wear debris. In addition, the wear debris may also have an impact on the morphology of the worn surface. Therefore, the wear debris will affect the corrugation by vibration and wear.