INFLUENCE OF FILLERS AND FIBER REINFORCEMENT ON ABRASIVE WEAR-RESISTANCE OF SOME POLYMERIC COMPOSITES

Fillers and fibre reinforcement increase the strength and stiffness of a polymer, and hence are effective in reducing wear in dry sliding conditions involving adhesion transfer or fatigue. However, in abrasive wear, such reinforcements are less effective and, in some cases, increase the abrasive wear rate. For a better understanding of this, abrasive wear studies were carried out on four types of polymers and their filler- and/or fibre-reinforced composites, abrading the polymer pins against an abrasive surface of silicon carbide paper of a fixed grit size. In most cases, the specific wear rate decreased with an increase in load. Except for bronze-filled polytetrafluoroethylene (PTFE), all the fillers (carbon, graphite, PTFE and MoS2) as well as short glass fibres increased abrasive wear. These results may be attributed to the reinforcement greatly reducing the ultimate elongation to fracture which in turn is a key factor in abrasive wear performance. The extent of counterface modification in multipass studies was observed to be another important factor in the abrasive wear performance of the composites. Worn pin and paper surfaces were also studied with scanning electron microscopy. © 1990.