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The press fitting zone in railway axles is critical from the fatigue resistance point of view, due to the combined action of contact stresses and wear phenomena, generally called fretting condition [1,2,3]. Under fretting conditions, short cracks nucleate because of cyclic contact shear stresses superimposed onto the fatigue stresses. Giannakopoulos, Lindley e Suresh [4] suggested an approach to fretting based on contact singular stress field, defining an analytical model (Crack Analogue) for SIF’determination. Another approach is that suggested by Kondo [5], which is based on the maximum local stress at the contact edge (Hot-Spot stress). In this paper the fretting problem in press-fittings made of high strength steels is analysed from the fracture mechanics point of view, considering the short crack effect. In fact it has been shown that the scale affects in fatigue strength, which are typical for high strength axles, can be assessed in terms of fatigue threshold for short cracks [6]: it appears therefore important to analize the fretting in terms of short cracks. The research has addressed in particular an experimental investigation and a numerical analysis where FE calculations together with WF have allowed us to determine the SIF at the tip of prospective cracks in the press-fitting. Fatigue limit was then estimated as the threshold condition of the prospective cracks.