Effect of Curve Radius of Rail on Rolling Contact Fatigue Properties of Wheel Steel

Rolling contact fatigue (RCF) and wear are inevitable problems for the infrastructure of modern railway. The effect of curve radius on the rolling contact fatigue properties of wheel steels under dry conditions was investigated on JD-1 wheel/rail simulation facility with Hertz contact theory and different attack angles. The rolling contact fatigue mechanism analysis of wheel with different curve radius was investigated in detail by observing fatigue cracks of the junction of cross section and wear surface of wheel specimens using optical microscopy and scanning electronic microscopy. The results indicate that there was an increase in the surface hardness of all specimens after testing due to work hardening. With a decrease in curve radius the wear volume of wheel steels increased,and the plastic flow layer became thicker and uneven,and the fatigue crack propagation of wheel steel sample intensified. Cracks continued to propagate into the bulk under alternating stress,thus creating severe fatigue damage.