Corrosion–fatigue of A1N railway axle steel exposed to rainwater

The fatigue properties of railway axle steels have not yet been thoroughly studied even though a number of axle failures are undoubtedly due to the combined effects of corrosion and fatigue. In this paper, the effects of corrosion by rainwater on the fatigue behavior of A1N steel, has been studied. The analysis of the results enabled us to establish that even the presence of a mild corrosive environment eliminates the fatigue limit, thus causing failures in the high-cycle fatigue regime (>106 cycles). The pit-to-crack transition and the crack propagation mechanism were then analyzed together with crack growth measurements on surface cracks. A modified Murtaza and Akid model was used to obtain the description of corrosion–fatigue crack growth data thus allowing us to obtain a conservative prediction of the S–N diagram subjected to artificial rainwater.