The Tribological and Sealing Properties of PFA Composites

Abstract

The polytetrafluoroethylene (PTFE) and perfluoroalkoxyperfluoropropyl vinyl ether (PFA) composites were prepared using carbon fiber (CF) and glass fiber (GF) as fillers. The effects of these fillers on the tribological and sealing properties were investigated. The tribological and sealing properties of the composites were evaluated by a wear tester and a seal test rig. Results showed that the incorporation of CF and GF both improved the wear resistance with composites, approaching wear rates as low as 10-6 mm3/N·m and lowered the seal's leakage of the PTFE/PFA composites. As described here, CF was more effective than GF in improving the wear rate. Notably, the wear rate of the PFA/CF composite is much less than that of the PTFE composites as the transfer film on the couple ring is much more unique, thick, smooth, and compact. The leakage of carbon fiber-filled PFA composite seal was lowered to 66% less than the traditional PTFE composite seals, which indicates better sealing properties.