THE EFFECT OF ZNF2, ZNS AND PBS FILLERS ON THE TRIBOLOGICAL BEHAVIOR OF NYLON-11

The tribological behavior of nylon 11 reinforced with particulate inorganic fillers was studied. The fillers used were ZnS, PbS and ZnF2. The composite specimens with different filler proportions were made by compression molding. The friction and wear experiments were run under ambient conditions in a pin-on-disk machine with the composite pin riding on the flat surface of a steel disk at a sliding speed of 1 m s-1 and under a normal load of 19.6 N. The influence of the fillers on transfer film formation was studied by optical and scanning electron microscopy. X-ray photoelectron spectroscopy (XPS) analysis was performed to detect the chemical changes during the wear process. In the case of PbS-nylon composite the filler was found to dissociate during the wear process and thus provide a strong adherent transfer film which led to increased wear resistance of the composite as compared to that of unfilled nylon. On the other hand, when ZnS and ZnF2 were used as fillers in nylon, the wear rate of nylon increased. The reasons for this behavior have been investigated by transfer film studies and XPS analysis.