Roughness evolution of wheel surface in a simulated wheel–rail contact

ABSTRACT The influence of the initial surface roughness on the wheel–rail contact has been a concern for railway systems especially since the introduction of rail grinding and wheel reprofiling as maintenance strategies. Currently, there are no universally accepted procedures for surface finishing of rails and wheels, so there is a need to keep studying the role of surface topography in reducing the maintenance costs and improving the wheel–rail system’s performance. This work studies the evolution of roughness of wheel samples during twin-disc tests performed to simulate wheel–rail contact up to 2.2 × 105 cycles under two different lubrication conditions. The results showed that under dry conditions the surfaces with larger kurtosis at the beginning of the tests had a better response to rolling contact fatigue. Under lubricated conditions, however, the effect of the initial roughness was less significant. GRAPHICAL ABSTRACT