Tribological Behavior of POM Composites Filled with PTFE and Ultra-fine Kaolin Particulates

Polyoxymethylene (POM) and POM composites filled with polytetrafluoroethylene(PTFE)and ultra-fine kaolin particulates were prepared by hot compression molding.Wear and friction tests were performed in a reciprocating sliding tribotester.The worn surfaces for POM and POM composites were examined by scanning electron microscopy.It is found that in the case of only PTFE filler,the wear rate and friction coefficient of POM+20%PTFE are much lower than those of the pure POM.The lowest steady state wear rate and coefficient of friction are obtained for the composite made with 20%PTFE and 7.5% kaolin.SEM analysis shows that the wear mechanism of pure POM is the combination of adhesive and abrasive wear,and that of POM composites is dominated by adhesive wear.