Microstructure and Electrical Contact Performance of Wires in Corrosion Air

Abstract

The high contact resistance of the corrosion products is more likely to cause contact failure. Based on service condition and natural environment of transmission and transformation equipment, the deterioration mechanism of electrical wires was investigated from the view of corrosion. The surface morphology of specimens after corrosion is observed by stereoscopic microscope and scanning electron microscope (SEM). Chemical constitution was examined by X-ray energy spectrum. The contact resistance was measured by four-point method. The experiment results show that the corrosion is mainly electrochemical corrosion. Humidity and air pollutants are the main factors of effecting the corrosion. The corrosion products formed on the surface layer of testing specimens is loose and uneven, and easy to fall off in the role of external force. The inner corrosion layer is dense and combined closely with the substrate. The EDS analysis results there is large quantity of O and S, and Cu oxide and sulfide are probably existed. The corrosion and pollution which come from the surrounding environment can increase the static contact resistance obviously, and the maximum value can reach to about 2000mΩ.