Assessment of the effects of residual stresses on fatigue life of real rough Surfaces in lubricated contact

This paper explores the possible effects of residual stress fields resulting from plastic deformation of real rough surface asperities on subsequent fatigue. A finite element model for the elastic-plastic contact of rough surfaces using profiles taken from the surfaces of unrun test disks is used to obtain the residual stress fields. These residual stresses are then added to the elastic stress distribution obtained from an elastohydrodynamic analysis to see the effects on fatigue damage and fatigue life at the scale of the surface roughness asperities. For the current paper, Micro-EHL simulations were carried out using the modelling techniques described in detail in reference and a strain-life model was used for predicting multiaxial fatigue life. The results show the accumulated damage due to residual stress effects is concentrated near the surface of particular asperity features.