Investigation on rolling contact fatigue and wear properties of railway rails

The rolling wear tests of rail material were conducted under unlubricated condition using a JD-1 wheel/rail simulation facility. The fatigue damage and wear behaviours of rail rollers were investigated in detail by examining the microhardness, wear volume, and wear scars using optical microscopy and scanning electronic microscopy. The results indicate that wear volume of a rail roller increases rapidly with the increase of axle load and decrease of curve radius. Wear volume of U71Mn rail is bigger than that of PD3 rail. It is observed that PD3 rail roller has some fatigue microcracks on the surface of wear scar. Furthermore, the microcrack propagates along depth direction with an angle of 15–30°. By comparison, U71Mn material has better fatigue resistance performance. The results indicate when the wear is serious, the fatigue damage is relatively slight. The relationship between fatigue crack damage and wear seems as competitive and restrictive coupling mechanisms.