Characteristics of plastic deformation field in polycrystalline fretting contacts

The plastic deformation field produced by fretting occurs over subsurface distances comparable to the grain size. Therefore, a more physically realistic constitutive model should be used to take into account the discrete grains and their crystallographic orientation distribution in this region to better capture the heterogeneity of the dislocation slip in the fretting damage process volume. This is accomplished by using a continuum crystal plasticity material model developed to represent these effects in Ti–6Al–4V. A two-dimensional finite element analysis is used to simulate an ideal fretting condition. This study examines how the characteristics of the plasticity produced by fretting changes with key fretting parameters including the normal contact force, the tangential force amplitude, and the coefficient of friction at the contact. The results produced using a continuum crystal plasticity model show that the distribution of plastic strain is highly heterogeneous and it contains both cyclic and ratchetting components.