Research on fretting Regimes of gold-plated copper alloy electrical contact material under different vibration amplitude and frequency combinations

Gold-plated copper alloy electrical contact materials are widely used in electrical interconnection to meet the requirements of high quality and high reliability for aviation and aerospace engineering. Not much is known about the fretting failure mechanism of such materials when placed in an environment with a high-frequency vibration. This paper investigates the fretting wear and corrosion behavior of gold-plated copper alloy contacts experimentally under different vibration amplitude and frequency combinations. Three typical degradation features are summarized. Relative surface morphology, element distribution, and wear track of worn surfaces are also analyzed. The fretting map, which can discriminate the fretting regimes with vibration amplitude and frequency combinations, is presented. The map can be clearly divided into the infinite electrical contact life zone, the oxidation-dominated failure zone, and the transient unstable conductivity failure zone. The appropriate sliding velocity is the critical condition for the sharply degradation of contact resistance after the gold coating has worn out. The results show that the dynamic contact resistance is significantly influenced by the coarser and irregular profile features of wear track induced by higher sliding speed, as well as the high resistive oxides debris or oxide metal mixture. (C) 2014 Elsevier B.V. All rights reserved.