TRANSFER FILM BONDING AND WEAR STUDIES ON CUS-NYLON COMPOSITE SLIDING AGAINST STEEL

The tribological behaviour of nylon 11 reinforced with lead sulphide filler was studied. The composite specimens with different filler proportions were made by compression moulding. 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. It was found that 35 vol.% PbS-nylon composite had the highest wear resistance. The friction and wear tests were run with this composite at different loads, speeds and counterface roughnesses. The wear rate increased considerably when the load was increased from 19.6 N to 39.2 N and the sliding speed from 1 m/s to 2 m/s, but the effect of these increases on the coefficient of friction was very small. The wear rate also increased abruptly when the surface roughness was increased from 0.11 to 0.3 mum but the coefficient of friction was not affected. It was found that the wear process was dominated by the transfer film that formed on the counterface. The transfer film and the worn surfaces were studied by scanning electron microscopy. XPS analysis indicated chemical bonding between the polymer composite transfer film and the steel counterface.