Experimental and numerical calculation data of contact stiffness/Surface roughness/HPT

Understanding the dynamic condition of the interface between a railway wheel and rail is important to reduce the risks and consider the effectiveness of countermeasures for tribological problems. Traditionally the difficulty in obtaining accurate non-destructive interfacial measurements has hindered systematic experimental investigations. Recently an ultrasound reflectometry technique has been developed as a direct observation method of a rolling-sliding interface, however the topography dependence under the high contact pressures in a wheel-rail contact has not been clarified. For this reason, a novel in-situ measurement of the contact stiffness using ultrasound reflectometry was carried out for three different levels of roughness. A contact pressure equivalent to that in a wheel-rail interface was achieved by using a high-pressure torsion test approach. The dynamic change of contact stiffness with slip was measured using ultrasound and the influence of roughness was investigated. The ...