fretting fatigue life prediction using the extended finite element method

in this work, an efficient procedure to predict fatigue lives in fretting fatigue problems is presented. this is accomplished by means of a combined initiation–propagation approach in which the extended finite element method (x-fem) is used. the procedure is verified by modelling several fretting fatigue tests available in the literature. the application of the x-fem enables to numerically evaluate the stress intensity factors (sifs) for cracks of different lengths emanating at the end of the contact zone and to estimate the propagation life corresponding to each of the tests. this propagation life is combined with the initiation life calculated using a multiaxial fatigue criterion (fatemi–socie). the predicted lives are then compared with the reported experimental lives, showing that the consideration of the crack–contact interaction through the numerical models tends to improve the life estimation when compared with a fully analytical approach. the procedure can be applied to more general fretting problems for which analytical solutions are not available.