SCLEROMETRIC AND TRIBOLOGICAL PROPERTIES OF POLYTETRAFLUOROETHYLENE WITH 40% BRONZE CONTENT FORMED BY ELECTRON BEAM IRRADIATION

Abstract

The paper focuses on the improvement of sclerometric and tribological properties of polytetrafluoroethylene (PTFE) with 40% bronze content implied by irradiation with an electron beam of 10 MeV and a power of 10 kW, in a dose of 26–156 kGy. The results of the study confirm that radiation modification of the PTFE-bronze composite causes structural changes induced by breaking of bonds in long PTFE chains and the branching of the polymer structure. As a result, an increase in such properties as the wear resistance ratio, Wβ, is observed. In addition, sclerometric tests have shown that, with an increase of the absorbed radiation dose, the grooveto- elevation area ratio changes during scratching, which indicates a change in the micromechanism of wear, i.e. the material undergoes ploughing. From the operating point of view, the most important were tribological tests, which were carried out on a pin-on-disc test stand (T-01). The tests showed a nearly fourfold reduction in wear at a load of 20 N and more than a threefold reduction at 40 N. Controlled radiation modification leads to improved properties of the PTFE-bronze composite, which may result in a wider range of its applications.