Fretting fatigue analysis of full-scale railway axles in presence of artificial micro-notches

Axles are one of the most critical components in railway vehicles and fretting fatigue is one of the open problems in this area. The need for a methodology for analyzing crack growth behavior under a fretting fatigue condition is essential, since determining it experimentally is a challenging task. In this case, a series of tests were performed on full-scale axles with artificial micro-notches. A series of three-dimensional finite element simulations was carried out to estimate fretting fatigue crack propagation path and residual lifetime of an existing crack beneath the axle-wheel's press-fit contact. Maximum tangential stress criteria were adopted to evaluate the crack propagation path. A model is proposed, based on the concept of cyclic R-curve and FE simulation results. The model is accurately estimating the fatigue limit of a full-scale axle in presence of artificial micro notches with an error less than 6% in comparison to the full scale experiments.