Literature Review and Preliminary Studies of Fretting and Fretting Fatigue Including Special Applications to Aircraft Joints.

摘要

This report contains a review of the literature pertinent to fretting and fretting fatigue including special applications to aircraft joints. An introduction is given outlining the importance of fretting and fretting fatigue failures. Proposed mechanisms of fretting and fretting fatigue are then discussed. Research in the literature indicates there are three stages to fretting fatigue life. The first is a period of crack nucleation, usually by adhesion and plastic deformation of contacting asperities in relative motion. Several other possible mechanisms are discussed as well. In the second stage, propagation of nucleated cracks is determined by the stress resulting from the surface tractions imposed by fretting. The results of several investigations of the stress state and its effect on the propagation of nucleated cracks are discussed. The stress state can either dramatically increase early crack propagation rates or retard crack propagation, depending upon the specifics of the contact under study. The third stage is a period of crack propagation during which fretting contact stresses are not significant to crack propagation. Fretting, Fretting fatigue, Crack nucleation, Stress state, Palliative behavior.