Mechanical and tribological characteristics of nano- and microcomposites with UHMWPE–PTFE polymer–polymer matrix

Abstract

In order to develop antifriction materials produced by extrusion, the mechanical and tribological characteristics of nanoand microcomposites with a hybrid ultrahigh molecular weight polyethylene (UHMWPE)–polytetrafluoroethylene (PTFE) matrix have been studied under the conditions of dry friction, boundary lubrication, and abrasive wear. Under the conditions of dry sliding friction, using the UHMWPE + 10 wt % PTFE matrix reduces the wear rate of the nanoand microcomposites by 10–30%; the mechanical characteristics of the microcomposites decrease substantially, while those of the nanocomposites diminish only slightly. Under boundary lubrication with distilled water, a similar effect of the size of the fillers on the wear resistance of the composites is observed. During abrasive wear, the wear resistance of the microcomposites significantly exceeds that of the UHMWPE + 10 wt % PTFE matrix, while the introduction of the nanosized fillers into the matrix changes its wear resistance only slightly. The supramolecular structure, the degree of crystallinity, and the topography of the worn surfaces of the developed materials are studied using scanning electron microscopy, differential scanning calorimetry, and light microscopy, as well as the mechanisms of the wear of these materials under the conditions of dry sliding friction and abrasive wear are discussed.