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This paper presents a numerically-based methodology for the prediction ofprobable sites of fretting fatigue cracks initiated at the common surfaces of axial dovetailjoints of an aero-engine compressor. The entrance angles of the initiated cracks and thepossibility of their development are modeled. Further, the paper suggests a possible surfacecracking mechanism for the formation of free relatively large material particles found byother researchers filling the mouth of cracks initiated by fretting fatigue. The proposalsresult from an incremental two-dimensional elastic-plastic finite element simulation of twoloading cycles applied to a sector representing the disc-blades assembly in a typicalcompressor. One cycle includes disc acceleration, full blade loading and unloading and finaldeceleration. The analysis assumes that (1) the fretted surfaces are frictional with acoefficient of 0.25 and (2) cracks likely initiate in regions of cyclic plasticity along the planeof maximum shear stress range and develop in regions of tension. The generated stress strainfield is multi axial and non-proportional. Thus, the present analysis searches for relevantcritical planes. The present results show that (1) multiple cracking with different orientationare probable in the fretted material nearest to the joint notch base (2) initiated cracks canhave cyclic tensile stress ranges sufficient for their stage II mode I growth and (3