Tribological behaviors of PTFE-based composites filled with bronze microparticles

Abstract

This research article deals with commercial polytetrafluoroethylene (PTFE)-based composites filled with 30% of bronze microparticles. This shade is used as guide rings in hydraulic cylinders. After a certain number of slip cycles, seal wear is one of the main causes of leaks in the hydraulic systems. To solve this problem, it is essential to act on the seal materials to increase its lifetime and consequently the lifetime of hydraulic systems. Excessive pressure on the seal causes a significant wear while a light contact causes lubricant leak. For both situations, we have a failure of the system. For this reason, it is necessary to have a perfect contact between the seal and the metal surface and simultaneously with minimal wear. This problem is the subject of our research works. We analyze, in this article, the tribological behavior of a PTFE/bronze composite under dry and lubricated sliding conditions for different frequencies and loads. An alternating linear motion ball/plane tribometer has been used to characterize friction and wear behavior of the material. Micrographic observation of wear track was taken with the optical microscope. The results showed the good friction behavior of material for low values of loads and frequencies and essentially for 33 N of load with 1 Hz frequency or for 81 N as normal load with 0.75 Hz frequency as well as lubrication improve the wear rate of the PTFE/bronze composite. Under lubrication, load and frequency become inversely proportional to friction coefficients.