Role of ambient temperature in the adhesion and damage characteristics of wheel/rail interface during rolling-sliding contact

Abstract

A systemic evaluation in laboratory were conducted to explore the effect of extreme temperature environment (−50 °C–60 °C) on the tribology properties of the wheel/rail rolling contact. Systemic analysis revealed the evolution rule of adhesion capacity of wheel/rail contact, the performance changes of wheel surface (including plastic deformation, hardening behavior, residual stress), and the damage morphology of the wheel surface and subsurface. The results showed that the seasonal damage to actual railway in the frigid zone can be reproduced through lab tests. The interface behavior and wear mechanism were affected by the service temperature. The adhesion capacity of the wheel/rail interface decreased with the increasing temperature, whereas it was relatively stable at low temperature and fluctuates obviously at high temperature. The high temperature accelerated the tribo-oxidation between the wheel/rail interface, but the brittleness of wheel material and the surface residual stress of worn surface increased as a result of the intensified surface shear action at cold environment. The wear mechanisms gradually transformed from abrasive wear, oxidation and adhesive wear to fatigue wear accompanied by the decrease of temperature.