Effects of graphite particle addition upon the abrasive wear of polymer surfaces

The abrasive wear performance of vinyl ester resins modified with various volume fractions (5, 10, 15, 20 and 30%) of graphite powder has been measured. Using a conveyor belt driven testing machine developed locally, it has been possible to realistically simulate the effect of three-body abrasive wear upon these graphite modified polymer samples. A comparison of the calculated dimensionless wear rates obtained for these surfaces reveals that the effect of the graphite powder depends strongly upon the volume fraction of particles in the resin matrix. It appears that, for intermediate volume fractions, the presence of graphite powder in the resin matrix reduces the abrasive wear of the polymer surface. Scanning electron microscopy has been used to probe the mechanisms of abrasive wear of the pure resin and graphite modified surfaces. It appears that the embedded graphite particles can act as a lubricant during the abrasion process thus reducing the wear rate. The effect of increasing graphite powder volume fraction upon the abrasive wear mechanism is discussed. (C) 2001 Kluwer Academic Publishers.