Influence of serpentine content on tribological behaviors of PTFE/serpentine composite under dry sliding condition

Abstract This paper presents a PTFE/serpentine solid lubricant composite that exhibits low friction coefficient and low wear rate. It is postulated that synergistic effect alters the dominant wear mechanism of PTFE matrix. In order to examine the influence of serpentine content on tribological properties of PTFE/serpentine composite, six blends of PTFE with serpentine (in the range of 0–30 wt.%) were evaluated using a MMU-5G friction and wear tester. Tests were carried out in standard laboratory conditions with a nominal contact pressure of 2.85 MPa and a sliding speed of 0.48 m/s. The friction coefficient of the composite, which was weakly dependent on serpentine content, was stable roughly from μ  = 0.10 to 0.12 during steady friction. Compared with the wear rate of unfilled PTFE, the wear resistance of PTFE/serpentine composite increased 24 times. However, the content of serpentine (5–30 wt.%) had little effect on wear rate of composite. The images of confocal laser scanning microscope (CLSM) revealed that the hybrid transfer film generated on the surface of mating pair is likely responsible for the lower wear rate obtained in these experiments.