Wear Analysis of CU-AL Coating on TI-6AL-4V Under Fretting

摘要

The effects of changes in the coefficient of friction (CoF) between the contacting surfaces on the fretting wear characteristics of Cu-Al coating on Ti-6Al-4V were investigated. This Cu-Al coating is part of a system that is applied to titanium turbine blades to reduce fretting at the interface. In the application, there is a solid lubricant that is added on top of the coating as an assembly aid and to help reduce the friction while the lubricant remains within the contact. Previous studies have researched the characteristics of the coating without the additional lubricant. In this study, liquid motor oil was applied to the contact region to simulate real-world conditions with a lower CoF. To characterize the wear, several methods were used, the most useful being the accumulated dissipated energy method. The accumulated relative displacement method did not take into account the differences between the tangential forces for tests conducted at different CoF values, whereas the dissipated energy method did. The wear characteristics of tests conducted in the current study were similar to those of a previous study, conducted at a higher CoF, when analyzed with the dissipated energy method, but this was most likely due to the ambiguity of the calculated wear volumes.