Key Findings

• The test of high strength rails installed in the high and low positions of a 5-degree curve concluded at 654 MGT without any rail developing an internal fatigue defect and with one EFB weld fracture at 210 MGT.
• Microhardness measured along the cross section of the rail diagonally from the gage corner showed a weak inverse relationship with gage corner wear averaging over all eight rail types.
• Assessment of residual stress on rails with heavy RCF showed the presence of high tensile stresses inside the head and at the metal lip that had formed at the bottom of the gage face due to gage wear and plastic deformation.
• To reduce damage to the flanges of the train wheels, the metal lip that had formed on the bottom of the gage face was either chipped off or removed with a switch grinder.
• There was some correlation between the change in RCF sub-surface crack direction and the change in residual stress bands below the surface, although other factors affecting changes in crack directions need to be investigated.