The Influence of the Organic Compounds on the Contaminated Electrical Contacts

Some organic compounds were proven to exist on the failed electrical contacts on the printed circuit boards in mobile phones. They mixed with both the dust particles and wear debris to cause contact failure under fretting conditions. The bonding function of organic compounds to particles and the influencing factors were analyzed theoretically. As one of the organic compounds found on the contaminated electrical contacts in failed mobile phones, the sodium lactate was chosen as the testing sample of the organics. The effects of sodium lactate on the contacts covered by the typical dust particles (quart, mica) were studied by using a vibration and a fretting simulation respectively. The critical content of sodium lactate to make the particles enter the contact interfaces under fretting was presented. The simulation results suggest that low content of organic compounds can degrade the contact reliability under dust contamination.