Effects of rail materials and axle loads on the wear behavior of wheel/rail steels

Abstract

Four kinds of rail steels were tested to investigate the wear behaviors of wheel–rail materials under three kinds of axle loads. Results indicate that the increase in axle load not only significantly enlarges the wear loss but also enlarges the depth and the length of the fatigue cracks. However, with the decreases in the hardness ratios, some ripples are exhibited on the surface, and the wear surfaces become much rougher; the subsurface analyses deliver the presence of extremely rough surface, and the deformation depths are irregular. The relationship between the total wear loss of the wheel/rail system and the hardness ratio indicates that the hardness ratio of wheel/rail steels has slight impact on the total wear loss at a low axle load; however, the decrease in the hardness ratio enlarges the total wear loss significantly at a high axle load. In summary, a quenched rail should be chosen for the heavy-haul railway, and the hardness of the wheel steel should be raised to a degree close to the rail. However, a hot rolled rail is much suitable for the high-speed railway, and the wheel hardness should be smaller than the rail.