Simple parameters to predict effect of surface damage on fretting fatigue

Fretting fatigue – Experimental and numerical approaches

“…contact slips and surface shear stress. Ding et al [12] introduced a simple parameter D fret2 to correct the multiaxial SWT criterion. According to the authors, the main contribution of D fret2 is that SWT can now handle the increase in the fatigue life in the transition domain between partial and gross slips.…”

A combined wear-fatigue design methodology for fretting in the pressure armour layer of flexible marine risers

“…Hence, it is proposed to adopt the Dfret fretting parameter, as proposed by Ding et al [45]. The Dfret method introduces a surface damage factor for the effects of fretting wear to a modified SWT approach, developed to incorporate the effects of slip and surface wear damage on crack initiation, as follows:…”

“…(τδ)th has been estimated here as a value slightly greater than the value at the partial slip -gross slip transition, based on FE simulations and following Ding et al [45]. For τδ < (τδ)th, the unmodified SWT value is used (i.e.…”

Effect of Solute Oxygen on Compressive Fatigue Strength of Spinal Fixation Rods Made of Ti–29Nb–13Ta–4.6Zr Alloys

“…Moreover, the crack vertically develops to the contacting surface at increasing depths. Therefore, it is considered that this crack from the fretted surface is the fretting fatigue crack, which occurs when contacting components experience small amplitude relative motion 12) ; it is too dif cult to examine the cross-sections of the Ti64 and 89O rods using an SEM because of the small widths (approximately 480 and 450 μm for the Ti64 and 89O rods, respectively) of the fretted surfaces.…”