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Fretting fatigue is a type of failure that may affect various mechanical components, such as bolted or dovetail joints, press-fitted shafts, couplings, and ropes. Due to its importance, many researchers have carried out experimental tests and analytical and numerical modelling, so that the phenomena that govern the failure process can be understood or appropriately modelled. Consequently, the performance of systems subjected to fretting fatigue can be predicted and improved. This paper discusses different aspects related to the finite element modelling of fretting fatigue. It presents common experimental configurations and the analytical solutions for cylindrical contact. Then, it discusses aspects of fretting fatigue crack initiation, such as crack location, orientation, and length, as well as stress averaging approaches. Then, it deals with the propagation stage; crack face interaction, orientation criteria, and crack growth rate are discussed. Lastly, additional aspects of recent research on fretting fatigue are reviewed: out-of-phase loading, cohesive zone modelling, wear effects, heterogeneity, and crystal orientation. Fretting fatigue is a phenomenon not well understood, and much more research is needed so that its understanding is increased and proper criteria and laws may be available for different cases. [ABSTRACT FROM AUTHOR]

Fretting is a phenomenon that occurs at the contacts of surfaces that are subjected to oscillatory relative movement of small amplitudes. Depending on service conditions, fretting may significantly reduce the service life of a component due to fretting fatigue. In this regard, the analysis of stresses at contact is of great importance for predicting the lifetime of components. However, due to the complexity of the fretting phenomenon, analytical solutions are available for very selective situations and finite element (FE) analysis has become an attractive tool to evaluate stresses and to study fretting problems. Recent laboratory studies in fretting fatigue suggested the presence of stress singularities in the stick-slip zone. In this paper, we constructed finite element models, with different element sizes, in order to verify the existence of stress singularity under fretting conditions. Based on our results, we did not find any singularity for the considered loading conditions and coefficients of friction. Since no singularity was found, the present paper also provides some comments regarding the convergence rate. Our analyses showed that the convergence rate in stress components depends on coefficient of friction, implying that this rate also depends on the loading condition. It was also observed that errors can be relatively high for cases with a high coefficient of friction, suggesting the importance of mesh refinement in these situations. Although the accuracy of the FE analysis is very important for satisfactory predictions, most of the studies in the literature rarely provide information regarding the level of error in simulations. Thus, some recommendations of mesh sizes for those who wish to perform FE analysis of fretting problems are provided for different levels of accuracy. [ABSTRACT FROM AUTHOR]