Copper Connections Research Articles

Surface Analysis of Fretting Damage in Electrical Connectors

AbstractA number of bolted-type tin-plated copper connectors commonly used for distribution transformers were examined using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Analysis (EDX). The connectors studied had been removed from service because of unsatisfactory performance under normal operating conditions as manifested either by overheating or instability.Detailed examination revealed the presence of extensive fretting damage in thecontacting surfaces. The fretting debris was composed mainly of tin oxide and oxidized base-metal particles. Localized melting and wear of the tin plating were also observed.