Wear and friction of aramid fiber and polytetrafluoroethylene filled composites

The friction and wear of 1.5 mm chopped aramid fiber reinforced polyamide 6,6 composites with and without polytetrafluoroethylene (PTFE) were characterized using a block on ring wear tester equipped with real time friction measurement capabilities. Experiments showed an optimum wear reduction at low levels of aramid fiber (5-15 wt.%). At higher aramid fiber levels an increase in wear rate was observed. However, with the addition of PTFE, up to 25 wt.% aramid fiber could be added to polyamide 6,6, resulting in a composite with extremely low wear and excellent mechanical properties. The major effect of the addition of PTFE was a reduction in the dynamic friction coefficient. (C) 1997 Elsevier Science S.A.