The Wear and Friction Behavior of Novel Polytetrafluoroethylene/Expanded Graphite Nanocomposites for Tribology Application

The tribological properties of polytetrafluoroethylene (PTFE)/expanded graphite (EG) nanocomposites were evaluated on a pin-on-disk wear tester under dry conditions for the first time. Scanning electron microscopy (SEM) was used to examine worn surfaces and debris of the worn samples. The wear rate and coefficient of friction of 2 wt. % EG filled nanocomposite were reduced approximately 162 times and 38%, respectively. The significant decrease in wear rate was attributed to a thin and tenacious transfer film on the counter-surface. However, when 5 wt. % EG was filled into the PTFE/EG nanocomposite, the wear rate did not decrease further.