Experimental investigation of the effects of precorrosion on the wear and rolling contact fatigue behaviors of wheel and rail materials

Wheel‒rail systems operate in open environments and are often disturbed by environmental factors, such as humid coastal climates that are susceptible to corrosion. The wear and damage behavior of CL60 steel wheel steel materials and U75V rail materials under different conditions of corrosion in advance (uncorroded wheel/uncorroded rail, precorroded wheel/uncorroded rail, uncorroded wheel/precorroded rail, and precorroded wheel/precorroded rail) were investigated via a rolling friction and wear test. An AK-Y250 neutral salt spray test chamber and an MMS-2A double-disc rolling friction and wear testing machine were used for this test. The results revealed that the friction coefficient and wear rate of the precorrosion wheel and precorrosion rail samples are greater than those of the uncorroded wheel and uncorroded rail samples. The surface damage to the uncorroded wheel and rail samples is mainly abrasive wear accompanied by surface cracks. However, precorrosion creates a larger furrow and spurs wear during the wear process by destroying the surface integrity of wheel and rail materials and creating a relatively loose corrosion layer. The size and depth of the spalling pits on the surface of the precorrosion wheel and precorrosion rail samples after wear are larger and deeper, and the degree of surface damage is greater than that of the uncorroded wheel and uncorroded rail samples after wear. The cracks in the uncorroded wheel and uncorroded rail samples propagate along the surface at a small angle, whereas those in the precorrosion wheel and precorrosion rail samples propagate at a larger angle to produce larger spalling pits.