Research On Fretting Wear Simulation Technique For Electrical Connector Based Celullar Automaton Theory

Fretting-induced failure is the major reason for invalidation of electrical connector. Fretting-induced failure mechanism is investigated in this paper. Rules of contact rough surface wear, particle deposition and transfer, oxidation film formation, contact resistance calculation are established based on Cellular Automaton (CA) theory. The simulation method is thoroughly designed for fretting wear according to the rules. The evolvement of contact pair is realized on discrete space and time domain. The degradation disciplinarians of contact rough surface and contact resistance are obtained. The conclusion can be a gist for fretting-induced failure analysis of electrical connector.Electrical connector is an important connection apparatus for electrical system. The characteristics of the electrical contacts are the key factors for the reliability of the system. Fretting-induced failure is the major reason for invalidation of electrical connector. Due to the complexity of fretting phenomenon, most research concentrate on the experimental aspects. In this paper, the failure mechanisms of fretting are analyzed in detail. A simulation approach is proposed based on cellular automaton (CA) theory. The degradation processes of contact surface and resistance under different fretting periods are achieved. The conclusions can be used for the failure analysis of electrical connector caused by fretting.The failure mechanisms are analyzed in the micro level. The contact of electrical connection pair is taken as the peak contact of rough surface. When plastic deformation occurs between the contact pair, adhesive wear and abrasion wear come out with the displacement of the contacts, which leave off the particles. Fretting changes the outline of the contact peak and the contraction resistance. At the same time, due to the oxidation of the contact surface, the particles and the base metal are oxidized and the wear resistance form. The resistance increases with the fretting wear, and finally leads to the failure of the connectors.Based on the failure mechanisms of fretting wear, the CA theory is adopted for the simulation of fretting wear. A series of local rules are constructed for the rough contact surface fretting, particle stack and transfer, oxidation layer formation and contact resistance calculation. The transformation process of the contact pair in discrete space and time domain is achieved. The degradation discipline of the contact resistance can also be accessed.The experiment device of fretting wear is applyed. Experiments under different loads and fretting periods are carried out. The variations of contact resistance are measured with micro-resistance meter. The surface morphology and compositions of experiment target are analyzed with laser scanning confocal microscope and scanning electron microscope. The experiment results can provide proof for the simulation results.