Corrosive effects of artificial rainwater on rolling contact fatigue on wheel and rail materials

Rolling contact fatigue (RCF) can damage and reduce the life of the wheel and rail materials due to the degradation of surfaces in contact. The complex combination of RCF with corrosion can also contribute to the rapid surface degradation of wheel and rails materials. It is a serious problem when a railway system's environmental conditions can lead to severe corrosion.Even in some cases, severe corrosion caused by rainwater was observed in some open warehouse facilities. This work aims to investigate the influence that corrosion by artificial rainwater has on the generation and propagation of cracks caused by RCF. Twin disk tests were conducted on disk specimens manufactured from wheel and rail sections with corrosion and without corrosion zones on their contact surfaces. Corrosion on the wheel and rail disk specimens was accelerated by the potentiodynamic anodic polarization (PAP) process. The results show that PAP tests can promote pits and micro-cracks formation with different morphologies and sizes in both materials. These surface defects in rail material can grow and accelerate the cracks from the surface and down deep into the subsurface. Finally, pitting and corrosion were removed by the wear action in the wheel material. However, longer and deeper cracks were observed. Results showed that corrosion significantly influences RCF development on rail material.