Effect of Operating Temperature and Application Quantity of Lubricants on the Fretting Behavior of Silver Plated Electrical Contacts

The use of lubricants on electrical connector contacts is essential for certain applications in order to reduce mating forces, minimize wear, and mitigate fretting corrosion. However, increasing performance requirements (e.g., operation at elevated temperatures) and regulatory restrictions are prompting a reassessment of lubricant selection. In this study, the influence of three lubricants (one oil and two greases), operating temperature (room temperature and 130°C), and applied volume (low, medium and high volume) on electrical contact resistance (ECR) and coefficient of friction (CoF) is investigated by means of fretting wear tests on silver-plated contacts. The results show that unlubricated silver contacts exhibit a longer stable phase at 130 °C than at room temperature. For lubricated contacts, service life is influenced by both temperature and lubricant volume. Certain lubricants demonstrate earlier fail at room temperature than at elevated temperatures. The findings highlight the importance of careful selection and optimization of lubricants for electrical connectors under varying environmental conditions.